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Journal Cover Catalysis Today
  [SJR: 1.348]   [H-I: 164]   [7 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0920-5861
   Published by Elsevier Homepage  [3175 journals]
  • Catalysis Today Special Issue: Catalysis for Sustainable Development,
           Peace and Prosperity
    • Authors: Ganapati D. Yadav; Mannepalli Lakshmi Kantam; Bhalachandra M. Bhanage
      First page: 1
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Ganapati D. Yadav, Mannepalli Lakshmi Kantam, Bhalachandra M. Bhanage


      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2018.03.067
      Issue No: Vol. 309 (2018)
       
  • Effect of calcium addition on Mg-AlOx supported Ni catalysts for hydrogen
           production from pyrolysis-gasification of biomass
    • Authors: Fangzhu Jin; Hongman Sun; Chunfei Wu; Huajuan Ling; Yijiao Jiang; Paul T. Williams; Jun Huang
      Pages: 2 - 10
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Fangzhu Jin, Hongman Sun, Chunfei Wu, Huajuan Ling, Yijiao Jiang, Paul T. Williams, Jun Huang
      Producing hydrogen from catalytic gasification of biomass represents an interesting process to facilitate the development of hydrogen economy. However, the design of catalyst is a key challenge for this technology. In this work, cost-effective Ca added Ni-based catalysts were developed and studied for producing hydrogen with a fixed-bed reactor. The relationship between Ca addition and the performance of catalyst in terms of the yield of hydrogen and catalyst deactivation (metal sintering and coke formation) was studied. The results showed that hydrogen production was largely enhanced when Ca was added, as the yield of hydrogen was enhanced from 10.4 to 18.2 mmol g−1 sample in the presence of Ca-based catalyst. However, the yield and concentration of hydrogen were kept at similar levels with the increase of Ca. By normalizing the yield of hydrogen in relation to the amount of Ni presented inside the catalyst, the hydrogen yield per mole of nickel was increased from 50 g Ni −1(0.1Ca catalyst) to 80 g Ni−1 (0.8Ca catalyst) when the Ca addition was increased from 10 mol% to 80 mol%. TPO-FTIR analysis of the experimented catalysts showed that 0.5 Ca catalyst had the highest amount of coke formation, in particular, most of the deposited carbons were amorphous which could deactivate the catalyst seriously. It is therefore concluded that the addition of cost-effective Ca could enhance the yield of hydrogen from biomass gasification. However, the concentration of Ca in the catalyst needs to be controlled to mitigate the generation of coke on the used catalyst.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2018.01.004
      Issue No: Vol. 309 (2018)
       
  • Mechanistic in-operando FT-IR studies for hydroprocessing of triglycerides
    • Authors: Mohit Anand; Saleem Akthar Farooqui; Jitendra Singh; Hari Singh; Anil Kumar Sinha
      Pages: 11 - 17
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Mohit Anand, Saleem Akthar Farooqui, Jitendra Singh, Hari Singh, Anil Kumar Sinha
      In-operando measurements were carried out for the first time to identify different intermediates and primary products formed during the conversion of lipids for catalytic as well as non-catalytic thermal hydroprocessing. Hydroprocessing of lipids was carried at 280–300 °C temperature, 40–60 bar pressure, 1500 Nl/L H2/Feed ratio and 1 h−1 space velocity in a fixed-bed tubular reactor. A high pressure metallic probe was used for collecting the FTIR spectra under these conditions. Under these conditions although the conversion of triglyceride molecules were complete, the deoxygenation reactions were less than 1%, with 6–7% carbon loss and 17–18% hydrogen loss into the gaseous phase corresponding to propane. In-operando FT-IR studies confirmed that depropanation (propane removal) is the primary reaction during catalytic hydroprocessing of triglycerides, along with formation of intermediates. For thermal hydroprocessing wide range of intermediates – alcohols, alkenes, ketones, anhydrides, ethers, acids, aldehyde and esters – were observed. Such intermediates indicate several undesirable coupling reactions such as CC bond formation, esterification, etherification and ketonization. For catalytic hydroprocessing only selective product intermediates were observed. Triglycerides hydroprocessing over Pd/Al2O3 catalyst predominantly produced carboxylic acid and aldehyde intermediates, along with very weak bands due to aromatics. Pd/C predominantly produced aldehydes with weak bands due to ketones. Sulfided CoMoP/Al2O3 catalyst also produced aldehydes predominantly, but also small quantities of carboxylic acids as intermediates, from trigycerides. IR bands due to alcohols, ethers, aromatics and cyclic ketones were observed at the later stage of reaction over CoMoP(S)/Al2O3 catalyst.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.12.021
      Issue No: Vol. 309 (2018)
       
  • Green catalytic processing of native and organosolv lignins
    • Authors: B.N. Kuznetsov; N.V. Chesnokov; I.G. Sudakova; N.V. Garyntseva; S.A. Kuznetsova; Yu.N. Malyar; V.A. Yakovlev; L. Djakovitch
      Pages: 18 - 30
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): B.N. Kuznetsov, N.V. Chesnokov, I.G. Sudakova, N.V. Garyntseva, S.A. Kuznetsova, Yu.N. Malyar, V.A. Yakovlev, L. Djakovitch
      Two ways of catalytic depolymerization of native and isolated wood lignins are described: the peroxide delignification of hardwood (aspen, birch) and softwood (abies) in the medium of acetic acid – water over TiO2 catalyst and the thermal dissolution of organosolv lignins (ethanol-lignin and acetone-lignin) in supercritical alcohols (ethanol and butanol) over solid Ni-containing catalysts. The catalyst TiO2 in rutile modification has the higher activity in wood peroxide delignification at 100 °C as compared to TiO2 in anatase modification. The results of kinetic studies and optimization of the processes of peroxide depolymerization of hardwood (aspen, birch) and softwood (abies) lignins in the medium of acetic acid – water over catalyst TiO2 (rutile) at mild conditions (≤100 °C, atmospheric pressure) are compared. The catalyst TiO2 initiates the formation of OH and OOH radicals from H2O2 which promote the oxidative fragmentation of wood lignin. In this case, the peroxide depolymerization of softwood lignin, constructed from phenylpropane units of guaiacyl-type proceeds more difficult than the hardwood lignins, mainly containing syringyl-type units. The solid and soluble products of peroxide catalytic delignification of wood under the optimized conditions were studied by FTIR, XRD, GC–MS and chemical methods. Regardless of the nature of wood the cellulosic products have a structure similar to microcrystalline cellulose. The soluble products mainly consist of monosaccharides and organic acids. Aromatic compounds are present only in a low amount which indicates the oxidative degradation of aromatic rings of lignin phenylpropane units under the used conditions of wood catalytic delignification. The processes of thermal dissolution of acetone-lignin and ethanol-lignin from aspen-wood in supercritical ethanol and butanol over Ni-containing catalyst (NiCu/SiO2, NiCuMo/SiO2) are compared. The composition, structure and thermal properties of organosolv lignins were studied with the use of FTIR, GPC, 1H – 13C HSQC NMR, DTA and elemental analysis. The influence of a composition of Ni-containing catalyst on the thermal conversion in supercritical butanol and ethanol of ethanol-lignin and acetone-lignin was established. The highest conversion of lignins (to 93% wt.) in supercritical alcohols and the highest yield of liquid products (to 90% wt.) were achieved at 300 °C in the presence of catalyst NiCuMo/SiO2. Scheme of green biorefinery of wood based on the use of non-toxic and low-toxic reagents (H2O2, H2O, acetic acid, ethanol, butanol) and solid catalysts (TiO2, NiCuMo/SiO2) is suggested.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.11.036
      Issue No: Vol. 309 (2018)
       
  • Benzyl methyl ether production from benzyl alcohol and methanol in
           carbonic water
    • Authors: Hidetaka Nanao; Hiroki Sasaki; Osamu Sato; Aritomo Yamaguchi; Masayuki Shirai
      Pages: 31 - 34
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Hidetaka Nanao, Hiroki Sasaki, Osamu Sato, Aritomo Yamaguchi, Masayuki Shirai
      Synthesis of benzyl methyl ether from benzyl alcohol and methanol in high-temperature carbonic water was studied in a batch reactor. Benzyl methyl ether formation was not observed by reacting benzyl alcohol with only methanol under supercritical conditions at 573K. On the other hand, benzyl methyl ether was formed by the treatment of benzyl alcohol in an aqueous methanol solution at 573K. 12% of benzyl methyl ether yield was obtained in aqueous methanol solution (methanol to water molar ratio of 0.025mol/0.11mol) at 573K in 60min and the yield enhanced to 33% by the addition of 18MPa of carbon dioxide to the aqueous solution. As the etherification is an acid catalyzed reaction, the protons derived from the dissociation of water molecules could be responsible for the etherification of benzyl alcohol in an aqueous methanol solution at 573K. The enhancement of benzyl methyl ether yield by the addition of carbon dioxide in aqueous methanol solution is caused by the increase of the number of protons derived from carbonic acid, which is formed in high-temperature liquid water under high-pressured carbon dioxide.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.11.021
      Issue No: Vol. 309 (2018)
       
  • Spectroelectrochemical analysis of TiO2 electronic states – Implications
           for the photocatalytic activity of anatase and rutile
    • Authors: Marcin Kobielusz; Kacper Pilarczyk; Elżbieta Świętek; Konrad Szaciłowski; Wojciech Macyk
      Pages: 35 - 42
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Marcin Kobielusz, Kacper Pilarczyk, Elżbieta Świętek, Konrad Szaciłowski, Wojciech Macyk
      The information on the electronic structure of nano- and microstructured semiconductors is crucial for their applications in photovoltaics, optoelectronics and photocatalysis. The distribution of intra-bandgap electronic states is one of the most relevant parameters which may be tuned in order to provide desired properties of a photoactive material. We propose the use of a modified spectroelectrochemical method for the characterisation of vacant electronic states distributed close to the edge of the titanium dioxide conduction band. These additional levels localized within the bandgap were semi-quantitatively characterized for several samples made of different polymorphs (or their blends) of TiO2. The applicability of the method for the determination of deep and shallow electron traps was confirmed. A quantitative analysis of the latter was also conducted for the selected samples. The presented approach provides also the information on the stability of electronic states, which is crucial for numerous practical applications.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.11.013
      Issue No: Vol. 309 (2018)
       
  • Second metals (Lanthanum, Cerium, and Yttrium) modified W/SiO2 catalysts
           for metathesis of ethylene and 2-butene
    • Authors: Narongrat Poovarawan; Kongkiat Suriye; Joongjai Panpranot; Wimonrat Limsangkass; Adisak Guntida; Francisco José Cadete Santos Aires; Piyasan Praserthdam
      Pages: 43 - 50
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Narongrat Poovarawan, Kongkiat Suriye, Joongjai Panpranot, Wimonrat Limsangkass, Adisak Guntida, Francisco José Cadete Santos Aires, Piyasan Praserthdam
      Lanthanum, cerium, and yttrium were added as a second metal on the WO3/SiO2 catalysts by the incipient wetness impregnation method with the atomic ratio between the second metal and tungsten 0.083 in order to improve the catalytic performances of W-based catalysts in the metathesis of ethylene and 2-butene. As revealed by various characterization results from X-ray diffraction, nitrogen physisorption, inductively coupled plasma optical emission spectrometry, ion-exchange titration, FT-Raman, ammonia temperature programmed desorption (NH3-TPD), and reactant-TPD, the dispersion of tungsten and adsorption properties were significantly improved by adding of the second metals, especially the adsorption of the mixed cis/trans-2-butene isomers. Hence, their catalytic performances were higher than the non-modified one when mixed cis/trans-2 butene isomers were used as the feeds. In addition, the presence of La as the second metal could also reduce coke formation on the catalysts probably by decreasing the ensemble site effect.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.11.012
      Issue No: Vol. 309 (2018)
       
  • One-pot synthesis of benzimidazole using DMF as a multitasking reagent in
           presence CuFe2O4 as catalyst
    • Authors: Kalidas B. Rasal; Ganapati D. Yadav
      Pages: 51 - 60
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Kalidas B. Rasal, Ganapati D. Yadav
      One pot synthesis of benzimidazole from o-nitroaniline was achieved by using CuFe2O4 as a catalyst. It comprises the reduction of o-nitroaniline followed by cyclization, without using an external H2 source. The thermal decomposition of DMF in situ generates CO, which undergo water gas shift reaction (WGSR) in the presence of CuFe2O4 to produce hydrogen. It reduces −NO2 (nitroaniline) to −NH2 (o-phenylenediamine, OPD). The further cyclisation of OPD to benzimidazole was done by using DMF as a C1 source, in the presence of magnetically separable CuFe2O4 as catalyst. This is the first example of its kind being reported here. The catalyst was prepared by a simple hydrothermal method, with an environmentally benign starting material. CuFe2O4 is cheap and reusable having very low toxicity. This is an economical synthetic protocol for benzimidazole from o-nitroaniline with 100% conversion in 12h with 97.5% selectivity. A variety of o-nitroaniline substrates were studied using the protocol with excellent conversion and selectivity in each case.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.10.014
      Issue No: Vol. 309 (2018)
       
  • Mesoporous tin oxide: An efficient catalyst with versatile applications in
           acid and oxidation catalysis
    • Authors: Pandian Manjunathan; Vijaykumar S. Marakatti; Prakash Chandra; Atul B. Kulal; Shubhangi B. Umbarkar; Raman Ravishankar; Ganapati V. Shanbhag
      Pages: 61 - 76
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Pandian Manjunathan, Vijaykumar S. Marakatti, Prakash Chandra, Atul B. Kulal, Shubhangi B. Umbarkar, Raman Ravishankar, Ganapati V. Shanbhag
      Mesoporous tin oxide was prepared by template assisted and template-free methods. As-prepared materials were calcined at various temperatures to generate different nature (Brønsted and Lewis), amount and strength of acidic sites. The physico-chemical properties of the catalysts were studied by XRD, N2 sorption, pyridine-FTIR, NH3-TPD, DRS UV-vis, TGA, SEM, TEM, 1H MAS and 119Sn MAS NMR analyses. The catalytic behavior of mesoporous tin oxide catalysts was evaluated for acetalization and ketalization of glycerol with benzaldehyde and acetone respectively under solvent free conditions. The catalytic performance of mesoporous tin oxide was compared with that of other conventional solid acid catalysts namely H-ZSM-5, H-mordenite, H-beta, Al-MCM-41, Al-SBA-15 and Al-TUD-1. The efficiency of mesoporous tin oxide was also tested for cyclohexene epoxidation reaction. The catalyst prepared by template assisted method showed excellent catalytic performance compared to other catalysts due the difference in nature and amount of acidic sites in the catalyst. Meso-SnO2-T-350 was stable and reusable catalyst for four cycles without any appreciable loss in activity, and therefore it offers a good catalyst for potentially wide applications.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.10.009
      Issue No: Vol. 309 (2018)
       
  • A study of CO2 reforming of CH4 for coal delivered gases over Ni-based
           catalysts
    • Authors: Wahab O. Alabi; Hui Wang; Wei Huang; Xiaodong Li
      Pages: 77 - 82
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Wahab O. Alabi, Hui Wang, Wei Huang, Xiaodong Li
      NiCo-Mg/Al-1.7, Ni-Mg/Al-1.6, Ni-Mg/Al-0, and NiCo-Mg/Al-0.3 Ni-based catalysts were used to test their performance in CO2 reforming of CH4 reaction for a coal gas feed mainly containing CO and H2 as well as CO2 and CH4 at 900°C and the ambient pressure. Compared to the performance in ideal feed of CO2 and CH4 balanced with N2, the smaller reaction rate in the coal gas observed over all the catalysts was barely due to the lower concentration of CO2 and CH4 in the feed. NiCo-Mg/Al-1.7 catalyst showed the highest activity and stability among the four catalysts owing to its right metallic NiCo alloy sites to activate CH4 and the strong basic sites to activate CO2. The TPO of the spent catalyst after 24h TOS showed no carbon formation. The other three catalysts facilitated more or less various formats of carbon formation depending on different surface properties, leading to the decay of catalytic activity along the TOS. The coal gas feed that contains very small amount of O2 helped mitigate the formation of the inactive graphitic carbon, possibly because O2 burned the carbon of this kind. This study will improve the efficiency of using coal gas by converting its to-be-emitted CO2 and CH4 into valuable CO and H2.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.10.008
      Issue No: Vol. 309 (2018)
       
  • The effect of titration time on the catalytic performance of Cu/CeO2
           catalysts for water-gas shift reaction
    • Authors: Hyun-Suk Na; Jae-Oh Shim; Won-Jun Jang; Kyung-Won Jeon; Hak-Min Kim; Yeol-Lim Lee; Da-We Lee; Seong-Yeun Yoo; Jong Wook Bae; Chandrashekhar V. Rode; Hyun-Seog Roh
      Pages: 83 - 88
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Hyun-Suk Na, Jae-Oh Shim, Won-Jun Jang, Kyung-Won Jeon, Hak-Min Kim, Yeol-Lim Lee, Da-We Lee, Seong-Yeun Yoo, Jong Wook Bae, Chandrashekhar V. Rode, Hyun-Seog Roh
      We herein report the preparation of ceria (CeO2) via a simple precipitation method for use as a catalyst support in the water-gas shift (WGS) reaction. More specifically, we optimized the titration time required to obtain highly active CeO2-supported catalysts for the WGS reaction. As such, Cu was employed as the active metal coupled with the CeO2 support. Notably, the CeO2–0 supported Cu catalyst (where the precipitant was immediately injected into a cerium nitrate solution) exhibited the highest CO conversion at a gas hourly space velocity of 36,050h−1. This high catalytic activity of the Cu/CeO2–0 catalyst was mainly due to its high Brunauer-Emmett-Teller (BET) surface area, enhanced Cu dispersion, high number of oxygen vacancies, and enhanced reducibility.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.10.007
      Issue No: Vol. 309 (2018)
       
  • Sensitizing with short conjugated molecules: Multimodal anchoring on ZnO
           nanoparticles for enhanced electron transfer characteristics, stability
           and H2 evolution
    • Authors: Leena George; Subrahmanyam Sappati; Prasenjit Ghosh; R. Nandini Devi
      Pages: 89 - 97
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Leena George, Subrahmanyam Sappati, Prasenjit Ghosh, R. Nandini Devi
      Sensitizing semiconductors with organic dyes is usually employed to improve efficiency of semiconductors towards visible light absorption and charge transport. However, till date most of the dyes are either noble metal based with complex and expensive synthesis procedure or have a very narrow absorption band. Further the photostability of the dyes is another important issue. In this work we have studied, using a combination of photophysical and computational methods, ZnO nanoparticles sensitized with transition metal free, cheap and easy to synthesize azoquinoline dye that has been designed to have multiple chelating sites, viz., carboxylic group and hydroxyl imine group as a photocatalyst for water splitting activity. We find that the presence of multiple chelating sites facilitates dual mode of anchoring on ZnO nanoparticles, which leads to enhanced photostability and H2 generation of the composite. This is attributed to the incorporation of resonance features in the dye that increases electron transfer between ZnO and dye in contrast to the charge accumulation and photo degradation observed in non-conjugated and single site anchoring counterparts. Electron transfer from ZnO to dye under UV light and reverse in visible light could be identified experimentally. Such simple designing aspects can aid in identifying better catalysts for photocatalytic water splitting.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.09.052
      Issue No: Vol. 309 (2018)
       
  • Understanding interactions between lignin and ionic liquids with
           experimental and theoretical studies during catalytic depolymerisation
    • Authors: Sandip Kumar Singh; Subhrashis Banerjee; Kumar Vanka; Paresh Laxmikant Dhepe
      Pages: 98 - 108
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Sandip Kumar Singh, Subhrashis Banerjee, Kumar Vanka, Paresh Laxmikant Dhepe
      Compared to H2SO4, Brønsted acidic ionic liquid (BAIL, [C3SO3HMIM][HSO4]) catalyzed depolymerization of lignin yielded higher concentration of low molecular weight products under mild conditions (120°C) as proven by GC and GC–MS. To comprehend this disparity in catalytic activity among H2SO4 and BAIL (at similar H+ concentration), experimental techniques [1D(1H) NMR, 2D(15N/1H HMBC) NMR and RAMAN] have been employed. Based on these studies, it has been proven that the transfer of electron density from substrate to the electron deficient imidazolium ring via formation of hydrogen bond between OH/OCH3 (substrate) and N1C2H2 N3− (cation) is possible, while the anion plays an important role. Further, density functional theory (DFT) calculations also corroborated this fact by showing a change in the bond angle and decrease in bond length (C2 H2 in imidazole), due to the presence of weak and strong hydrogen bonding between the substrate and IL.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.09.050
      Issue No: Vol. 309 (2018)
       
  • Size-controllable gold nanoparticles prepared from immobilized
           gold-containing ionic liquids on SBA-15
    • Authors: Etty N. Kusumawati; Daisuke Nishio-Hamane; Takehiko Sasaki
      Pages: 109 - 118
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Etty N. Kusumawati, Daisuke Nishio-Hamane, Takehiko Sasaki
      A series of gold nanoparticles (AuNPs) with controllable size were prepared from immobilized gold-containing ionic liquid on SBA-15 (AuCl_me-Im@SBA-15) at room temperature. AuNPs size and shape could be controlled inside porous SBA-15 in the presence of immobilized 1-methyl-3-(3-trimethoxysilyl- propyl)-imidazolium chloride by controlling a concentration and a feed rate of a reducing agent NaBH4. The smallest AuNPs with the average size of 1.6nm was obtained at a fixed feed rate of 0.2ml/min with 4mM NaBH4. The transformation of AuNPs shape from spherical to capsule-like NPs was observed at low feed rate of 0.04ml/min. The prepared AuNPs catalysts were characterized by TEM, XPS, FTIR, and XRD. The catalyst with the smallest NPs, AuNP(1.6nm)_me-Im@SBA-15, exhibited the highest catalytic performance in p-nitrophenol hydrogenation reaction at room temperature. Moreover this catalyst was reusable up to four recycle processes.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.09.012
      Issue No: Vol. 309 (2018)
       
  • Selective synthesis of 2, 5-furandicarboxylic acid by oxidation of
           5-hydroxymethylfurfural over MnFe2O4 catalyst
    • Authors: Anil B. Gawade; Akhil V. Nakhate; Ganapati D. Yadav
      Pages: 119 - 125
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Anil B. Gawade, Akhil V. Nakhate, Ganapati D. Yadav
      Development of green catalytic processes using biobased feedstock for valuable chemicals such as 5-hydroxymethylfurfural (HMF) is hotly pursued. 2, 5-Furandicarboxylic acid (FDCA), a bio-based alternative to terephthalic acid was efficiently synthesized by oxidation of HMF using MnFe2O4 spinel structured magnetic nanoparticles (MNPs) and tert-butyl hydroperoxide as an oxidant. MnFe2O4 catalyst showed the highest activity and selectivity and gave 85% yield of FDCA at 100°C in 5h. The higher activity of MnFe2O4 catalyst is due to the variable oxidation state of manganese. The combination of MnFe2O4 catalyst and TBHP oxidant requires less time and energy compared to other reported processes of FDCA synthesis. Also, many reported methods have used a homogeneous base for FDCA synthesis which is totally avoided in the current process. The concentration profiles of reactants and products were established and kinetics determined. The effects of various reaction parameters were studied to validate kinetic model. The catalyst was easily recycled due to its magnetic property and showed good catalytic activity up to four cycles. All metal ferrites were characterized by different analytical techniques. The catalyst maintained its fidelity.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.061
      Issue No: Vol. 309 (2018)
       
  • Electrochemical oxidation of ethylene glycol in a channel flow reactor
    • Authors: N.L. Chauhan; V. Dameera; A. Chowdhury; V.A. Juvekar; A. Sarkar
      Pages: 126 - 132
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): N.L. Chauhan, V. Dameera, A. Chowdhury, V.A. Juvekar, A. Sarkar
      Electrochemical oxidation of ethylene glycol has been studied in a channel flow reactor (CFR) on high surface area platinum at three different flow rates and varying potentials. Sampled current potential obtained from chronoamperometry experiments agrees well with the voltammetry data reported in the literature. The current at any potential was observed to be a weak function of the flow rate. The products of the oxidation reaction have been identified using high performance liquid chromatography (HPLC). In addition to all the usual C2 fractions (glycolaldehyde, glycolic acid, glyoxylic acid, glyoxal and oxalic acid) already reported, an important C1 fraction (formic acid) has been observed in significant quantities at low flow rates. The results of this study suggest cleavage of CC bond, though the exact pathway remains unclear. Further, distinct changes in the product profile (amount of different C1 and C2 fractions) were observed with flow rate. Glycolic acid was the only product that was observed in significant quantities at all flow rates. The results suggest interplay of contact time of the reactants with the thin film catalyst, kinetics and reaction pathway and demonstrate the usefulness of a channel flow reactor.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.053
      Issue No: Vol. 309 (2018)
       
  • Ultrasound assisted synthesis of citronellol laurate by using Novozym 435
    • Authors: Ankita Galgali; Sarita D. Gawas; Virendra K. Rathod
      Pages: 133 - 139
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Ankita Galgali, Sarita D. Gawas, Virendra K. Rathod
      The present work represents the ultrasound assisted synthesis of citronellol laurate using Novozym 435 as a biocatalyst in a solvent free condition. The reaction was evaluated by two methods, one factor at a time and central composite design (CCD) by RSM. Initially, the first method produced maximum conversion up to 93.36% using optimal conditions (1:4 acid to alcohol ratio, 2% enzyme loading, 60°C temperature, 300rpm, 80W power, 50% duty cycle and 25kHz frequency). After estimation of parameters, the experimental design expert was used to evaluate the effect of molar ratio, enzyme loading, duty cycle and ultrasound power on the citronellol laurate synthesis. The optimal conditions for the ultrasound assisted synthesis of citronellol laurate was found to be: molar ratio of 1:4.2 lauric acid to citronellol, enzyme loading 2.11, ultrasound power 83.85W and 48.54% duty cycle. Under these conditions, it was possible to obtain 96.43% of conversion in a shorter time (40min). The Novozym 435 could be recycled in 5 successive reaction cycles. The Ordered Bi Bi kinetic model has well fitted for ultrasound assisted synthesis of citronellol laurate.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.052
      Issue No: Vol. 309 (2018)
       
  • Rapid evaluation of coke resistance in catalysts for methane reforming
           using low steam-to-carbon ratio
    • Authors: Jiyoon Jeon; Seongju Nam; Chang Hyun Ko
      Pages: 140 - 146
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Jiyoon Jeon, Seongju Nam, Chang Hyun Ko
      The formation and subsequent accumulation of coke is one of the major reasons for the catalyst deactivation in methane reforming reaction. Although the investigation of coke-resistant catalysts is closely related to their long-term stability of given catalysts, it takes a long time to quantitatively measure the amount of carbon deposition on catalysts under normal reaction operational conditions. To overcome this problem, we used the steam deficient reaction condition, i.e. a low steam-to-carbon ratio (S/C) of 0.5 to accelerate the carbon deposition on catalysts. In this condition, the base catalyst of 10wt.% Ni/alumina rapidly lost its catalytic activity, indicating fast coke deposition. However, adding proper additives, such as Ru among various precious metals (Ru, Rh, Pt, and Pd) and alkaline earth metals (Mg, Ca, Sr, and Ba) with the appropriate loading (5wt.%) effectively suppressed coke formation. The optimized catalyst composition is 0.5wt.% Ru/5wt.% Mg/10wt.% Ni/alumina, which displayed coke resistance in the long-term stability test of steam methane reforming and 40h test of dry reforming of methane. These experimental results indicate that the method developed in this study is useful for the rapid evaluation of given catalysts for their coke resistance.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.051
      Issue No: Vol. 309 (2018)
       
  • Reductive-hydroformylation of 1-octene to nonanol using fibrous Co3O4
           catalyst
    • Authors: Sachin S. Bhagade; Shivkumar R. Chaurasia; Bhalchandra M. Bhanage
      Pages: 147 - 152
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Sachin S. Bhagade, Shivkumar R. Chaurasia, Bhalchandra M. Bhanage
      This work reports, reductive-hydroformylation of 1-octene to nonanol in the presence of fine fibrous cobalt oxide (Co3O4) nano-catalyst prepared via urea reduction method under phosphine-free and additive free condition. Co3O4 nano-catalyst was prepared by the wet chemical method and was characterized using various instrumental techniques like FEG-SEM, EDS, XRD, TPR and FTIR. The effects of various reaction parameters such as temperature, synthesis gas (CO/H2) pressure/ratio, catalyst loading, solvent and time were studied. The reaction was successfully achieved in tetrahydrofuran (THF) as the solvent medium. This reaction believed to takes place through the generation of HCox(CO)y active catalyst species. The Co3O4 nano-catalyst could be recycled up to three consecutive cycles.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.022
      Issue No: Vol. 309 (2018)
       
  • Selective glycerolysis of urea to glycerol carbonate using combustion
           synthesized magnesium oxide as catalyst
    • Authors: Godfree P. Fernandes; Ganapati D. Yadav
      Pages: 153 - 160
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Godfree P. Fernandes, Ganapati D. Yadav
      Synthesis of glycerol carbonate is industrially significant due to its varied applications in several areas such as paints, coatings, detergents, membranes, polyurethane foams, solvents, etc. In this work, a green process was developed for the synthesis of glycerol carbonate from glycerolysis of urea using MgO as catalyst. The new catalytic route is very attractive with minimal unit operations, since ammonia released as co-product can easily be separated from system and used in urea synthesis. Magnesium oxide was synthesized by combustion method. The catalyst was characterized completely using SEM, XRD, TPD and N2 adsorption-desorption. A systematic study was conducted to evaluate the effect of various parameters on initial rate of reaction, conversion and selectivity. Thus, reaction mechanism and kinetics were established. Magnesium oxide exhibited excellent catalytic behaviour in the production of glycerol carbonate with conversions up to 71% in 6h with 100% selectivity at 150°C and atmospheric condition. The catalyst is easily recoverable and reusable in subsequent cycles of reaction without any loss of activity.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.021
      Issue No: Vol. 309 (2018)
       
  • Insight into a catalytic process for simultaneous production of biodiesel
           and glycerol carbonate from triglycerides
    • Authors: Manali S. Dhawan; Ganapati D. Yadav
      Pages: 161 - 171
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Manali S. Dhawan, Ganapati D. Yadav
      Biodiesel, a renewable liquid fuel derived from triglycerides, is a promising alternative to compensate for the increasing demand of petro-diesel. However, 10% w/w glycerol is co-produced in the biodiesel production process which reduces the efficiency. The present work deals with the one-pot simultaneous co-production of biodiesel and glycerol carbonate from in-situ coproduced glycerol using hydrotalcite as a catalyst. Uncalcined hydrotalcite, calcined hydrotalcite and rehydrated hydrotalcite were screened for their activity towards the reaction in terms of conversion of soybean oil triglycerides and selectivity of glycerol carbonate. Uncalcined hydrotalcite served best for this purpose. At oil to methanol mole ratio of 1:90 and oil to DMC mole ratio of 1:30, the reaction gave 97.3% conversion of triglycerides and 93.2% selectivity of glycerol carbonate at 150°C in 3h at a catalyst loading of 0.0125g/cm3. The virgin and reused catalysts were well characterized using various analytical techniques which reveals the presence of basic as well as acidic sites with high surface area and ordered pore-size distribution. Effects of various experimental parameters on the conversion of triglycerides and selectivity to glycerol carbonate were studied to interpret the reaction kinetics. The kinetic rate constants and the activation energies were calculated. Reusability study of the catalyst was done up to two cycles and the catalyst was found to be robust and reusable.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.020
      Issue No: Vol. 309 (2018)
       
  • Synthesis and applications of ordered and disordered mesoporous zeolites:
           Present and future prospective
    • Authors: Rajendra Srivastava
      Pages: 172 - 188
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Rajendra Srivastava
      Zeolites are microporous aluminosilicates that are used extensively for a wide variety of industrial applications. Applications of microporous zeolites are limited to transformations of small molecules due to the pore diffusion limitation imposed by the microporous network structure. In order to overcome this limitation, zeolites with inter-/intra-crystalline mesopores are generally preferred. This review article presents the details of various strategies for the preparation of mesoporous zeolites with inter-/intra-crystalline mesopores. A wide range of soft templates and additives is described in details for their use in the synthesis of mesoporous ZSM-5 and Beta zeolites. A brief report on the applications of mesoporous zeolites in various acid catalyzed reactions, involving large organic molecules, is provided in this article. Another important feature of this article is that it summarizes the applications of mesoporous zeolites in the electrochemical detection of various physiologically important biomolecules and organic/inorganic water pollutants. Further, the role of mesoporous zeolites based electrode materials for direct methanol fuel cell application is presented. Finally, the potential role of mesoporous zeolites in the field of biomedical engineering, particularly as a bone implant material, is summarized.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.017
      Issue No: Vol. 309 (2018)
       
  • Selective hydrogenation of levulinic acid into γ-valerolactone over Cu/Ni
           hydrotalcite-derived catalyst
    • Authors: Shyam Sunder R. Gupta; Mannepalli Lakshmi Kantam
      Pages: 189 - 194
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Shyam Sunder R. Gupta, Mannepalli Lakshmi Kantam
      A highly efficient and selective Cu/Ni hydrotalcite-derived catalytic system has been developed for liquid phase hydrogenation of levulinic acid (LA) into γ-valerolactone (GVL) under mild reaction conditions. Full conversion of LA with 100% selectivity towards GVL has been achieved at 140°C, 30bar H2 pressure in 3h using dioxane as a solvent over activated Cu/Ni/Mg/Al catalyst with 0.75/0.5/1/1 molar ratios of metal cations in the synthesis mixture. It has been found that the catalytic activity increases with increasing copper content, while the selectivity towards GVL formation increases with increasing nickel content and surface Lewis basic sites (SLB) resulting from MgO promotes the hydrogenation of LA under mild reaction conditions by activating the CO group of LA for hydrogenation. Influence of various parameters such as reaction temperature, hydrogen pressure, reaction time and the nature of solvent have been studied. A series of Cu-based catalysts have been prepared by co-precipitation method and characterized using XPS, XRD, FEG-SEM, EDS, NH3-TPD, CO2-TPD, TPR and N2 physical adsorption techniques. Furthermore, the catalyst was easily reactivated and recycled for four times without significant loss in catalytic activity and selectivity towards GVL formation.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.007
      Issue No: Vol. 309 (2018)
       
  • Bifunctional role of Pd/MMT-K 10 catalyst in direct transformation of
           furfural to 1,2-pentanediol
    • Authors: Nandan S. Date; Rajeev C. Chikate; Hyun-Seog Roh; Chandrashekhar V. Rode
      Pages: 195 - 201
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Nandan S. Date, Rajeev C. Chikate, Hyun-Seog Roh, Chandrashekhar V. Rode
      The acid functionality of montmorillonite clay K 10 (MMT-K 10) was found to play a key role to give 1,2-pentanediol (1,2-PeDO) in Pd catalysed furfural hydrogenation. Among various Pd loadings on MMT-K 10, 3% Pd/MMT-K 10 catalyst exhibited excellent performance giving almost complete conversion of FFR and the highest selectivity of 66% to 1,2-PeDO. Py-IR of the catalyst evidenced the presence of Brønsted acidity which was responsible in C5-O cleavage of furan ring after the formation of furfuryl alcohol which is the first step intermediate in FFR hydrogenation. At a lower temperature of 140°C, highest selectivity of 56% was achieved for FAL while increase in temperature to 220°C, enhanced the selectivity to 1,2-PeDO. Keeping the temperature constant at 220°C, increase in H2 pressure from 500 to 750psig, resulted in decrease in 1,2-PeDO selectivity from 66 to 34% with proportionate increase in THFAL selectivity. Thus as per the requirement, the product selectivities can be tailored by varying the reaction parameters suitably. Several control experiments were also performed the results of which combined with the characterization data allowed to propose a plausible reaction pathway for the formation of 1,2-PeDO.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.002
      Issue No: Vol. 309 (2018)
       
  • Ordered mesoporous nanocrystalline titania: A promising new class of
           photocatalyic materials
    • Authors: A. Alagarasi; P.U. Rajalakshmi; K. Shanthi; P. Selvam
      Pages: 202 - 211
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): A. Alagarasi, P.U. Rajalakshmi, K. Shanthi, P. Selvam
      We report the photocatalytic activity of uniform-sized nanocrystalline mesoporous titania synthesized via surfactant-mediated hydrothermal method. All the prepared catalysts were systematically characterized by various analytical, spectroscopic and imaging techniques. The characterization results indicate that all the catalysts under investigation possess uniform-sized nanocrystalline particles having mesoporous pore structure with narrow pore size distribution. The phase transformation occurs from anatase, brookite to rutile phase while increasing the calcination temperature. The performance of mixed phase titania for the photocatalytic degradation of 4-chlorophenol was analyzed. These catalysts show much higher activity than commercial titania (Aeroxide; P-25) owing to synergistic effect of stable mesoporous structure and mixed crystalline phases of titania.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.001
      Issue No: Vol. 309 (2018)
       
  • Ni-Mn/γ-Al2O3 assisted plasma dry reforming of methane
    • Authors: Debjyoti Ray; P. Manoj Kumar Reddy; Ch. Subrahmanyam
      Pages: 212 - 218
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Debjyoti Ray, P. Manoj Kumar Reddy, Ch. Subrahmanyam
      The potential for a DBD plasma reactor for methane dry reforming was studied. The plasma dry reforming was carried out by integrating the discharge with a heterogeneous catalyst and the results were compared with plasma reactor alone. For this purpose, NiO/Al2O3 and NiO-MnO2/Al2O3 catalysts were prepared, characterized and integrated with the discharge in an in-plasma configuration. The trend of the CH4 and CO2 conversion, H2, CO yield, carbon balance and the energy efficiency of the process were analyzed. Typical results indicated that a high conversion was achieved with catalytic DBD compared to plasma alone, whereas, the best syngas ratio was obtained with plasma alone. The highest CH4 and CO2 conversion achieved was ∼28.4% and ∼13.2% with 25% packing of the discharge volume. The best yield of H2 and CO was found to be 7% and 10.5, respectively, whereas the best energy efficiency obtained was 2.76mmol/kJ with Ni-Mn/Al2O3 packed DBD. The results are correlated by estimating the breakdown voltage, charge, total capacitance and average electron energy for DBD reactor with and without catalytic integration. Optical emission spectroscopy (OES) was employed to understand the active species formed during the dry reforming.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.07.003
      Issue No: Vol. 309 (2018)
       
  • Selective and reusable Pt-WOx/Al2O3 catalyst for deoxygenation of fatty
           acids and their esters to diesel-range hydrocarbons
    • Authors: Sagar Janampelli; Srinivas Darbha
      Pages: 219 - 226
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Sagar Janampelli, Srinivas Darbha
      Tungsten oxide promoted platinum catalysts (Pt-WOx/Al2O3) of varying composition were prepared by wet impregnation method and reduced in hydrogen atmosphere. X-ray powder diffraction and photoelectron spectroscopy revealed that Pt is completely reduced to metallic state while tungsten is in +6 and +5 oxidation states. Pt crystallite and particle sizes increased (from 1.2 to 1.4nm and 2.5 to 3nm, respectively) in presence of WOx (CO-chemisorption and transmission electron microscopy). Tungsten addition augmented strong acid sites. It enhanced significantly the catalytic activity of Pt/Al2O3 in deoxygenation of fatty acids and their methyl esters. Tungsten altered the reaction pathway from decarbonylation/decarboxylation to hydrodeoxygenation. A catalyst with 4wt% Pt and 8wt% W exhibited high catalytic performance. Complete conversion of oleic acid and octadecane product selectivity in the range 67.1–80.8% was obtained. Pt-WOx/Al2O3 is a stable and reusable fatty acid deoxygenation catalyst.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.06.030
      Issue No: Vol. 309 (2018)
       
  • Noble metal-free CeO2-based mixed oxides for CO and soot oxidation
    • Authors: Deboshree Mukherjee; Benjaram M. Reddy
      Pages: 227 - 235
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Deboshree Mukherjee, Benjaram M. Reddy
      ‘Three-way catalytic technology’ has been successfully implemented in automobile industries for cleaning of auto exhaust gases from 1980’s onward. Supported noble metal catalysts with ceria (CeO2) as the redox promoter have been employed for this technology. However, these catalytic materials have some drawbacks in terms of high light off temperature, catalyst poisoning and drop of activity, heavy metal pollution, etc. Hence, this technology is under active investigation throughout for the sake of better performance. Considerable research efforts have been devoted to develop new advanced materials. Noble metal-free CeO2-based mixed oxides, which can be deployed as potential substitutes, have been investigated at length with the goal to overcome the limitations like loss of stability and activity at elevated temperatures, improvement of oxygen storage/release capacity (OSC), and so on. However, the use of proper dopants at optimum concentration and tuning of the shapes, size and morphology of the nanoparticles via controlled synthesis is a challenging task, since it improves the features of CeO2. In this article, we have reviewed the influence of these factors on the properties of ceria-based materials and their catalytic efficiencies in CO and soot oxidation reactions.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.06.017
      Issue No: Vol. 309 (2018)
       
  • Biocatalytic resolution of (R,S)-styrene oxide using a novel epoxide
           hydrolase from red mung beans
    • Authors: Manoj P. Kamble; Ganapati D. Yadav
      Pages: 236 - 241
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Manoj P. Kamble, Ganapati D. Yadav
      Chiral epoxides are commercially important starting materials for synthesis of active pharmaceutical ingredients and agrochemicals. A major challenge in synthetic chemistry is to produce such compounds in high yield with purity. There have been numerous current advances in the field of biotransformation particularly, hydrolytic kinetic resolution of epoxides using newly discovered enzymes (e.g. epoxide hydrolases). Epoxide hydrolase (EH) is a promising biocatalyst for the synthesis, as it enables racemic preparation of various epoxides and/or their corresponding diols in enantiopure form. In present study, partially purified epoxide hydrolase enzyme isolated from red mung beans was used for the first time for enantioselective hydrolysis of (R,S)-styrene oxide to (R)-1-phenyl-1,2-ethanediol. It was found that the optimal reaction temperature, buffer pH, and substrate concentration were 40°C, 7.5 and 20mM, respectively. Under optimized reaction conditions, conversion, V max and Km values were ∼44%, 8.2×10−3 mol/L/min and 4.5mol/L, respectively.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.06.013
      Issue No: Vol. 309 (2018)
       
  • Low temperature hydrogenation of carbon dioxide into formaldehyde in
           liquid media
    • Authors: Fan Liang Chan; Garen Altinkaya; Nicholas Fung; Akshat Tanksale
      Pages: 242 - 247
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Fan Liang Chan, Garen Altinkaya, Nicholas Fung, Akshat Tanksale
      There is a growing demand for formaldehyde (HCHO) in various industrial applications, however, current industrial processes cannot be considered as green. There is an urgent need to develop an environmentally friendly and efficient method to produce this chemical. Our previous work introduced a novel HCHO production method via catalytic hydrogenation of CO in liquid media. This work demonstrates for the first time that HCHO can be synthesized via catalytic hydrogenation of CO2 in liquid media. Unlike CO conversion however, CO2 conversion is not believed to be a single step conversion. The conversion may proceed via two possible pathways: Route A − CO2 hydrogenation into formic acid (HCOOH) followed by dehydration-hydrogenation into HCHO; and Route B − CO2 conversion into CO via reverse water gas shift reaction, followed by direct hydrogenation of CO into HCHO similar to our previous report. To study feasibility of Route A, HCOOH conversion into HCHO was tested in methanol solvent and Pt-Cu/alumina showed the best conversion and highest yield. This partly confirmed our hypothesis that dehydration-hydrogenation of HCOOH into HCHO is feasible and hence HCOOH may act as an intermediate. However, the rate of HCHO production was substantially lower than the rate of HCOOH consumption, which suggests that there may be other competing reactions, such as decomposition of HCOOH. No intermediates could be detected in one-pot conversion of CO2 into HCHO in our investigation, which may be due to their low concentration and/or rapid consumption to form the products. Therefore, this study concludes that both the routes are likely for the conversion of CO2 into HCHO in a liquid phase reaction.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.06.012
      Issue No: Vol. 309 (2018)
       
  • Photocatalytic CH activation and oxidative esterification using Pd@g-C3N4
    • Authors: Sanny Verma; R.B. Nasir Baig; Mallikarjuna N. Nadagouda; Rajender S. Varma
      Pages: 248 - 252
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Sanny Verma, R.B. Nasir Baig, Mallikarjuna N. Nadagouda, Rajender S. Varma
      Graphitic carbon nitride supported palladium nanoparticles, Pd@g-C3N4, have been synthesized and utilized for the direct oxidative esterification of alcohols using atmospheric oxygen as a co-oxidant via photocatalytic CH activation.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.06.009
      Issue No: Vol. 309 (2018)
       
  • Porous iron-phosphonate nanomaterial as an efficient catalyst for the CO2
           fixation at atmospheric pressure and esterification of biomass-derived
           levulinic acid
    • Authors: Swarbhanu Ghosh; Piyali Bhanja; Noor Salam; Resmin Khatun; Asim Bhaumik; Sk. Manirul Islam
      Pages: 253 - 262
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Swarbhanu Ghosh, Piyali Bhanja, Noor Salam, Resmin Khatun, Asim Bhaumik, Sk. Manirul Islam
      Chemical fixation of CO2 and synthesis of biofuels through convenient reaction pathways are very demanding in the context of sustainable and eco-friendly catalysis. Herein, we report the synthesis of iron-phosphonate nanoparticles HPFP-1(NP) through the simple chemical reaction between hexamethylenediamine-N,N,N′,N′-tetrakis-(methylphosphonic acid) and FeCl3 under hydrothermal conditions. The material has been characterized by transmission electron microscopy (TEM), powder X-ray diffraction (PXRD), N2 adsorption/desorption studies and FE-SEM. This porous material showed high catalytic activity for the synthesis of organic carbonates from a wide range of epoxides at room temperature in the presence of CO2 at atmospheric pressure. This nanocatalyst also exhibited excellent catalytic activity for the conversion of levulinic acid into alkyl levulinates. The HPFP-1(NP) catalyst showed high recycling efficiency in these catalytic reactions.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.05.093
      Issue No: Vol. 309 (2018)
       
  • Selected fundamentals of catalysis and electrocatalysis in energy
           conversion reactions—A tutorial
    • Authors: Emil Roduner
      Pages: 263 - 268
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Emil Roduner
      Electrochemical devices for energy conversion and storage applications have little in common with conventional electrochemistry. A significant advantage is the conversion of chemical into electrical energy and vice-versa, minimizing the amount of waste heat. Upscaling power density to values reaching up to 1Wcm−2 at current densities exceeding 1Acm−2 goes along with downscaling transport distances of reaction partners inside and between electrodes. Substrates undergo structure- and element-specific interactions with electrode surfaces which are therefore not only interfaces for the exchange of electrons, rather they should be regarded as specific catalytic surfaces which together with the applied electrical bias potential determine the spectrum of available products. An understanding of these interactions is still in its infancy for many of the relevant systems, and therefore the developments are largely empirical and driven by intuition, supported by quantum-chemical calculations and spectroscopic methods. The manuscript is of tutorial nature and addresses the differences between electrocatalysis in energy conversion reactions and conventional electrochemistry, and it reveals what catalytic transformations at electrode surfaces have in common with traditional heterogeneous catalysis.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.05.091
      Issue No: Vol. 309 (2018)
       
  • One pot selective transformation of biomass derived chemicals towards
           alkyl levulinates over titanium exchanged heteropoly tungstate catalysts
    • Authors: Srinivasa Rao B.; Krishna Kumari P.; Dhana Lakshmi D.; Lingaiah N.
      Pages: 269 - 275
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Srinivasa Rao B., Krishna Kumari P., Dhana Lakshmi D., Lingaiah N.
      Alkyl levulinates were produced from biomass derived carbohydrates (glucose, fructose) and platform chemicals (5-hydroxy methyl furfural, furfuryl alcohol and levulinic acid) under feasible reaction condition using titanium modified heteropoly tungstate catalysts. Titanium exchanged heteropoly tungstophosphoric acid (TPA) with variation in titanium content were prepared and various spectroscopic methods were used to characterize these catalysts. The exchange of Ti in TPA essentially created new Lewis acidic sites. The existence of both Lewis and Bronsted acid sites of titanium containing TPA Keggin were directing the selective synthesis of alkyl levulinates from different starting materials. The partially exchanged Ti0.75TPA catalyst yielded about 92–98% of alkyl levulinates from 5-hydroxy methylfurfural, furfuryl alcohol and levulinic acid, whereas 63 and 21% yield was achieved by the alcoholysis of fructose and glucose respectively. Different types of alkyl levulinates were also synthesized from alcoholysis of furfuryl alcohol. The reaction conditions were optimized to achieve maximum yield of alkyl levulinates. The catalyst was easily separated and reused without any loss in activity.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.05.040
      Issue No: Vol. 309 (2018)
       
  • V2O5/ZrO2 as an efficient reusable catalyst for the facile, green, one-pot
           synthesis of novel functionalized 1,4-dihydropyridine derivatives
    • Authors: Sandeep V.H.S. Bhaskaruni; Suresh Maddila; Werner E. van Zyl; Sreekantha B. Jonnalagadda
      Pages: 276 - 281
      Abstract: Publication date: 1 July 2018
      Source:Catalysis Today, Volume 309
      Author(s): Sandeep V.H.S. Bhaskaruni, Suresh Maddila, Werner E. van Zyl, Sreekantha B. Jonnalagadda
      A practical method is designated for the one-pot, multicomponent synthesis of 1,4-dihydropyridine derivatives by cyclo-condensation of aromatic aldehydes, 5,5-dimethyl-1,3-cyclohexanedione, acetoacetanilide and ammonium acetate. Using ethanol as solvent and V2O5/ZrO2 as heterogeneous catalyst, ten novel 1,4-dihydropyridines were synthesized at room temperature (Reaction time <20min). XRD, TEM, SEM and BET analysis were used to characterize the catalyst materials. Simple work-up, green solvent, short reaction times, moderate reaction conditions and excellent yields (90–96%) are the attractive features of this novel approach. With no need of chromatographic separation, the reaction product is easily separable in pure form.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.05.038
      Issue No: Vol. 309 (2018)
       
  • Continuous flow (micro-)reactors for heterogeneously catalyzed reactions:
           Main design and modelling issues
    • Authors: Ilenia Rossetti
      Pages: 20 - 31
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Ilenia Rossetti
      Continuous flow chemistry is a rapidly developing branch in organic and drugs synthesis, whereas it is common practice in heterogeneous catalysis for base chemicals production. Heterogeneously catalysed synthetic protocols are being developed and can take advantage of the reaction and reactor engineering experience at the macro-scale, provided that suitable models are applied to the micro- and meso-reactors in use. The main process parameters that define possible mass, heat and momentum transport limitations in heterogeneous catalytic reactors are reviewed. Specific models applying such concepts to microreactors are proposed. Finally, examples are reported of heterogeneously catalysed reactions carried out in microreactors for different applications.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.09.040
      Issue No: Vol. 308 (2018)
       
  • Towards industrial furfural conversion: Selectivity and stability of
           palladium and platinum catalysts under continuous flow regime
    • Authors: Weiyi Ouyang; Alfonso Yepez; Antonio A. Romero; Rafael Luque
      Pages: 32 - 37
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Weiyi Ouyang, Alfonso Yepez, Antonio A. Romero, Rafael Luque
      Furfural is an important biorefinery platform chemical, derived from hemicelluloses which represent an import fraction of lignocellulosic biomass feedstocks and waste streams originating from them. Recently, promising results have been reported on the hydrogenation of furfural, although the selectivity still may be improved. Most of these studies dealt with batch hydrogenation, however, hydrogenation in continuous flow is preferable for industrial applications. In this work, we compare the conversion, selectivity and stability on-stream in continuous flow regime of lab-synthesized and commercial palladium and platinum catalysts.
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      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.07.011
      Issue No: Vol. 308 (2018)
       
  • Tuning nano-nickel selectivity with tin in flow hydrogenation of
           6-methyl-5-hepten-2-one by surface organometallic chemistry modification
    • Authors: Małgorzata Zienkiewicz-Machnik; Ilona Goszewska; Anna Śrębowata; Adam Kubas; Damian Giziński; Grzegorz Słowik; Krzysztof Matus; Dmytro Lisovytskiy; Marcin Pisarek; Jacinto Sá
      Pages: 38 - 44
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Małgorzata Zienkiewicz-Machnik, Ilona Goszewska, Anna Śrębowata, Adam Kubas, Damian Giziński, Grzegorz Słowik, Krzysztof Matus, Dmytro Lisovytskiy, Marcin Pisarek, Jacinto Sá
      Chemoselective flow hydrogenation of 6-methyl-5-hepten-2-one was performed over nano-nickel catalysts. The parent catalyst composed solely of nickel nanoparticles grafted on the polymeric resin exhibited high activity and selectivity towards CC bond saturation but its modification with small quantities of tin significantly increased its ability to perform CO bond hydrogenation. The post-synthetic modification of the parent catalyst was achieved by surface organometallic chemistry approach and performed in the same flow micro-reactor, which was used for the catalytic studies, providing a methodology for online modification of parent catalysts.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.062
      Issue No: Vol. 308 (2018)
       
  • Promotional effect of water in the clean continuous production of
           carvacrol from carvone
    • Authors: Pedro Benavente; Fernando Cárdenas-Lizana; Mark A. Keane
      Pages: 45 - 49
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Pedro Benavente, Fernando Cárdenas-Lizana, Mark A. Keane
      We have studied the effect of water on the selective conversion of biomass-derived carvone to carvacrol over Pd/Al2O3 (mean Pd size=3nm). Full selectivity to carvacrol was observed in H2O (H2O:Carvone=1:12-6:1) without H2 or at an inlet H2:Carvone=1:6. Carvacrol generation from carvone involves double bond migration with keto-enol tauromerisation. The formation of hydrogenation products (carvotanacetone and carvomenthone) was a feature of reaction at higher H2 content. The incorporation of water (H2O:Carvone≤1:3) with hydrogen (H2:Carvone=1:6-2:1) increased carvacrol production rate to deliver 100% yield. A higher H2O content lowered rate due to competition with carvone for surface active sites. Our results demonstrate the benefits of carvacrol production in continuous flow relative to conventional batch processes allowing full selective transformation under mild reaction conditions.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.09.059
      Issue No: Vol. 308 (2018)
       
  • An investigation on AuPt and AuPt-Bi on granular carbon as catalysts for
           the oxidation of glycerol under continuous flow conditions
    • Authors: Davide Motta; Felipe J Sanchez Trujillo; Nikolaos Dimitratos; Alberto Villa; Laura Prati
      Pages: 50 - 57
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Davide Motta, Felipe J Sanchez Trujillo, Nikolaos Dimitratos, Alberto Villa, Laura Prati
      AuPt/AC and Bi modified AuPt/AC were prepared by impregnation using activated granular carbon as support followed by chemical reduction. The catalysts were characterized by means of Atomic Absorption Spectroscopy (AAS), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The catalysts were evaluated in the base free glycerol oxidation at mild reaction conditions in a continuous flow fixed bed reactor. Experimental parameters, such as, contact time (Liquid Hourly Space Velocity: LHSV), temperature and O2 flow have been varied in order to evaluate catalytic performance in terms of activity, selectivity and long-term stability. Under optimized reaction conditions AuPt/AC showed a high selectivity to glyceric acid (68.3%) whereas Bi-AuPt/AC promoted the oxidation of the secondary alcohol giving a selectivity to dihydroxyacetone (DHA) of 48.1% at 28% conversion, one of the most promising values reported in the current literature. Long-term catalytic performance was carried out for 80h and revealed a reasonable good stability of AuPt/AC against deactivation and leaching, whereas structural modification and subsequent changes in the catalytic reactivity were envisaged for Bi-AuPt/AC catalyst.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.10.012
      Issue No: Vol. 308 (2018)
       
  • MnO2-nanowire@NiO-nanosheet core-shell hybrid nanostructure derived
           interfacial Effect for promoting catalytic oxidation activity
    • Authors: Yuzhou Deng; Wenxiang Tang; Wenhui Li; Yunfa Chen
      Pages: 58 - 63
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Yuzhou Deng, Wenxiang Tang, Wenhui Li, Yunfa Chen
      Nanostructure-derived interfacial effect plays a great role in enhancing catalytic activities. Herein, a MnO2 nanowires@NiO nanosheets core-shell hybrid nanostructure was successfully prepared by uniformly decorating NiO nanosheets on the one-dimensional MnO2 nanowires. The physi-chemical properties of the MnO2 and MnO2@NiO were characterized by using XRD, BET, SEM, H2-TPR and XPS techniques. Compared to the single MnO2 nanowires, the MnO2@NiO nanocomposite with better low-temperature reducibility and more active surface oxygen species exhibited much better performance in complete oxidation of benzene, giving the temperatures for 100% benzene conversion of 320°C under the conditions of 1000ppm benzene in air and space velocity of 120,000mLg−1 h−1 while the value over pure MnO2 was 380°C. The novel hetero-interface constructed between MnO2 and NiO core-shell nanostructures might make a great contribution on this significantly promoting effect.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.07.007
      Issue No: Vol. 308 (2018)
       
  • Spatial, temporal and quantitative assessment of catalyst leaching in
           continuous flow
    • Authors: Elena M. Barreiro; Zhimian Hao; Luis A. Adrio; J. Ruud van Ommen; Klaus Hellgardt; King Kuok (Mimi) Hii
      Pages: 64 - 70
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Elena M. Barreiro, Zhimian Hao, Luis A. Adrio, J. Ruud van Ommen, Klaus Hellgardt, King Kuok (Mimi) Hii
      Catalyst leaching is a major impediment to the development of commercially-viable processes conducted in a liquid-phase. To date, there is no reliable technique that can accurately identify the extent and dynamics of the leaching process in a quantitative manner. In this work, a tandem flow-reactor system has been developed, which allowed us to distinguish between surface-catalyzed reactions from those occurring in solution by comparing%conversion at the exit of each reactor (S1, S2) corresponding to predominance of heterogeneous/homogeneous reactions (spatial) and two different residence times (temporal). A multiscale model is subsequently established to quantify the two types of reaction rate and simulate the catalyst leaching from a cross-coupling catalyst, PdEncat™ 30; including: (1) a multi-particle sizes model for catalyst scale; and (2) a dispersion model for reactor scale. The results show that catalyst leaching occurs via more than one process, and that the homogeneous Pd-catalyst (leached from the immobilized catalyst and dissolved in the flow) dominates the reaction and possesses a much higher activity than the heterogeneous (immobilized) Pd-catalyst. Additionally, the change of leached Pd stream inside reactors can be predicted along with the axial direction and the reaction time through the reactor-scale dispersion model.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.10.013
      Issue No: Vol. 308 (2018)
       
  • 3DOM LaMnAl11O19-supported AuPd alloy nanoparticles: Highly active
           catalysts for methane combustion in a continuous-flow microreactor
    • Authors: Xiangyu Li; Yuxi Liu; Jiguang Deng; Yang Zhang; Shaohua Xie; Xingtian Zhao; Zhiwei Wang; Guangsheng Guo; Hongxing Dai
      Pages: 71 - 80
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Xiangyu Li, Yuxi Liu, Jiguang Deng, Yang Zhang, Shaohua Xie, Xingtian Zhao, Zhiwei Wang, Guangsheng Guo, Hongxing Dai
      Three-dimensionally ordered macroporous (3DOM) LaMnAl11O19 and xAuPd y /3DOM LaMnAl11O19 (x =0.44−1.91wt%; y =1.80−1.86) were prepared via the polymethyl methacrylate (PMMA)-templating and gas bubble-assisted polyvinyl alcohol (PVA)-protected reduction routes, respectively. Physicochemical properties of the samples were characterized by a number of analytical techniques. Catalytic activities of the samples were measured for methane combustion in a continuous-flow microreactor. It is shown that the LaMnAl11O19 in each of the samples was hexagonal in crystal structure, and all of the samples possessed a good-quality 3DOM architecture with a surface area of 24.4−28.2m2/g. The Au–Pd nanoparticles (NPs) with an average size of 2.8nm were uniformly dispersed on the macropore walls of 3DOM LaMnAl11O19. The 1.91AuPd1.80/3DOM LaMnAl11O19 sample performed the best for methane combustion (T 50% =342°C and T 90% =402°C at a space velocity of 20,000mL/(gh)). The deactivation of the 1.91AuPd1.80/3DOM LaMnAl11O19 catalyst induced by water vapor introduction was reversible, whereas that induced by SO2 addition was irreversible. It is concluded that the good catalytic activity of 1.91AuPd1.80/3DOM LaMnAl11O19 was related to its good-quality 3DOM structure, highly dispersed Au–Pd NPs, high adsorbed oxygen species concentration, good low-temperature reducibility, and strong interaction between Au–Pd alloy NPs and 3DOM LaMnAl11O19.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.07.024
      Issue No: Vol. 308 (2018)
       
  • Targeting a Mirabegron precursor by BH3-mediated continuous flow reduction
           process
    • Authors: Sonia De Angelis; Claudia Carlucci; Modesto de Candia; Gabriele Rebuzzini; Paolo Celestini; Massimiliano Riscazzi; Renzo Luisi; Leonardo Degennaro
      Pages: 81 - 85
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Sonia De Angelis, Claudia Carlucci, Modesto de Candia, Gabriele Rebuzzini, Paolo Celestini, Massimiliano Riscazzi, Renzo Luisi, Leonardo Degennaro
      A continuous-flow reduction of (R)-2-hydroxy-N-[2-(4-nitrophenyl)ethyl]-2-phenylacetamide, involved in the synthetic pathway of Mirabegron, has been developed. This study demonstrated the possibility to safely handling BH3 complexes within microfluidic reactors using 2-MeTHF as greener alternative to traditional solvents, and without requiring any additive such as DMI. In addition, NMR and HPLC purity analysis revealed that the sole by-product of this process is the diamine 3, which wouldn’t affect the following synthetic steps towards Mirabegron.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.09.058
      Issue No: Vol. 308 (2018)
       
  • Novel polystyrene-immobilized chiral amino alcohols as heterogeneous
           ligands for the enantioselective arylation of aldehydes in batch and
           continuous flow regime
    • Authors: José Augusto Forni; Luiz Fernando Toneto Novaes; Renan Galaverna; Julio C. Pastre
      Pages: 86 - 93
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): José Augusto Forni, Luiz Fernando Toneto Novaes, Renan Galaverna, Julio C. Pastre
      Six different ligands derived from (S)-proline, (2S,4R)-4-hydroxyproline, (S)-tyrosine and (S)-phenylalanine were synthesized and screened in homogeneous phase for the enantioselective arylation of aldehydes using mixed organozinc reagents. The best ligands were immobilized on the Merrifield resin and evaluated in batch and continuous flow regimes. In batch, up to 89% yield and 90:10 enantiomeric ratio were obtained. In continuous flow regime, we explored the examples that were more challenging in batch, being able to obtain the desired product in 88% yield and 94:6 of enantiomeric ratio in residence time as low as 1.5min.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.08.055
      Issue No: Vol. 308 (2018)
       
  • Organocatalytic α-trifluoromethylthiolation of silylenol ethers: Batch vs
           continuous flow reactions
    • Authors: Said Said Abubakar; Maurizio Benaglia; Sergio Rossi; Rita Annunziata
      Pages: 94 - 101
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Said Said Abubakar, Maurizio Benaglia, Sergio Rossi, Rita Annunziata
      This work describes the organocatalytic α-trifluoromethylthiolation of silylenol ethers using N-(trifluoromethylthio)saccharin as trifluoromethylthiolating reagent that is activated by the presence of catalytic amounts of a Lewis base. Tetrahydrothiophene was identified as the best organocatalyst and it was successfully employed to promote the synthesis of different α-trifluoromethylketones; the reaction has been performed under a traditional batch methodology and under continuous flow conditions. In general, yields obtained using the traditional batch process were higher than those observed when the reaction was performed under flow conditions. However, short reaction times, higher productivity and higher space time yields were observed when a flow system process was employed. Preliminary DFT calculations were also performed in order to elucidate the mechanism of the reaction.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
      DOI: 10.1016/j.cattod.2017.09.013
      Issue No: Vol. 308 (2018)
       
  • Flow Chemistry &amp; Catalysis – Where do we stand and where do
           we need to go'
    • Authors: Gianvito
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Gianvito Vilé


      PubDate: 2018-04-25T00:47:41Z
       
  • Multiphase flow processing in microreactors combined with heterogeneous
           catalysis for efficient and sustainable chemical synthesis
    • Authors: Jun Yue
      Abstract: Publication date: 15 June 2018
      Source:Catalysis Today, Volume 308
      Author(s): Jun Yue
      The convergence of continuous flow chemistry and microreactor technology creates numerous possibilities towards the development of an efficient and sustainable chemical synthesis. In this field, the combination of heterogeneous catalysis and multiphase flow processing in microreactors represents an important approach. This review presents a summary of the recent progress on the utilization of wall-coated and packed-bed microreactors for carrying out heterogeneously catalyzed gas-liquid and liquid-liquid reactions, with a focus on the microreactor operation principles and selected reaction examples with promising application potential. Finally, an outlook on the future development trends is provided.
      Graphical abstract image

      PubDate: 2018-04-25T00:47:41Z
       
 
 
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