02385nas a2200181 4500008004100000022001400041245010400055210006900159260000800228300001400236490000600250520172500256100002101981700002502002700002402027700002902051856012302080 2018 eng d a2470-134300aSingle-pot reductive rearrangement of furfural to cyclopentanone over silica-supported Pd catalysts0 aSinglepot reductive rearrangement of furfural to cyclopentanone  cAUG a9860-98710 v33 a

Direct one-pot hydrogenation of furfural (FFR) to cyclopentanone (CPO) was investigated over different silica-supported Pd catalysts. Among these, 4% Pd on fumed silica (4%Pd/f-SiO2) showed remarkable results, achieving almost 98% furfural (FFR) conversion with similar to 89% selectivity and 87% yield to cyclopentanone at 165 degrees C and 500 psig H-2 pressure. More interestingly, the fumed-silica-supported catalyst tuned the selectivity toward the rearrangement product, i.e, cyclopentanone, whereas all of the other supports were found to give ring hydrogenation as well as side chain hydrogenation products due to their parent Bronsted acidity and specific support properties. X-ray diffraction data revealed the presence of different phases of the face-centered cubic lattice of metallic Pd along with lowest crystallite size of 15.6 nm in the case of the silica-supported Pd catalyst. However, Pd particle size was found to be in the range of 5-13 nm with even dispersion over the silica support, confirmed by high-resolution transmission electron microscopy analysis. While studying the effect of reaction parameters, it was observed that lower temperature gave low furfural conversion of 58% with only 51% CPO selectivity.. Similarly, higher H-2 pressure lowered CPO selectivity with subsequent increase in 2-methyl furan and ring hydrogenation product 2-methyl furan and 2-methyl tetrahydrofuran. Thus, as per the requirement, the product selectivity can be tuned by varying the type of support and/or the reaction parameters suitably. With the help of several control experiments and the characterization data, a plausible reaction pathway was proposed for the selective formation of cyclopentanone.

1 aDate, Nandan, S.1 aKondawar, Sharda, E.1 aChikate, Rajeev, C.1 aRode, Chandrashekhar, V. uhttps://library.ncl.res.in/content/single-pot-reductive-rearrangement-furfural-cyclopentanone-over-silica-supported-pd01970nas a2200241 4500008004100000022001400041245013700055210006900192260000800261300001600269490000600285520111900291653002101410653001301431653001201444653001801456653002201474100002301496700002301519700002501542700002901567856013201596 2020 eng d a2365-654900aCooperative acid-base sites of solid Ba-Zr mixed oxide catalyst for efficient isomerization of glucose to fructose in aqueous medium0 aCooperative acidbase sites of solid BaZr mixed oxide catalyst fo cOCT a12505-125130 v53 a

Efficient and highly selective isomerization of glucose to fructose was achieved by using the inexpensive Ba-Zr mixed metal oxide catalyst. Catalyst was prepared by varying Ba-Zr ratios using co-precipitation method. Various phases formed, planes exposed, morphology, elemental composition and particle size, basic site density and strength, oxidation state of elements were well studied by using various characterization techniques. The XRD analysis clearly indicates the presence of Ba+2 and Zr+4 in the form of BaO, ZrO2 and BaZrO3 phases. The SEM and HR-TEM images indicate that, Ba-Zr (2 : 1) catalyst prepared showed uniform morphology with spherical and rod-shaped particles ranging from 300 to 600 nm. Under the optimized reaction conditions Ba-Zr (2 : 1) catalyst exhibited excellent results in terms of 57 % of glucose conversion with 89 % selective formation of glucose. The presence of both acidic as well as basic sites play vital roles in activating the substrate molecules to selectively yield fructose. Ba-Zr (2 : 1) catalyst showed excellent recyclability performance up to four recycles.

10aCo-precipitation10afructose10aglucose10aisomerization10amixed metal oxide1 aShaikh, Samrin, S.1 aPatil, Chetana, R.1 aKondawar, Sharda, E.1 aRode, Chandrashekhar, V. uhttps://library.ncl.res.in/content/cooperative-acid-base-sites-solid-ba-zr-mixed-oxide-catalyst-efficient-isomerization-glucose01866nas a2200241 4500008004100000022001400041245011300055210006900168260000800237300001400245490000800259520106200267653001801329653002101347653001301368653001301381653002201394100002501416700002201441700002601463700000501489856013001494 2023 eng d a0008-403400aActivity performance and kinetics for glycerol carbonylation with urea over Zn-Co mixed metal oxide catalyst0 aActivity performance and kinetics for glycerol carbonylation wit cAPR a2075-20930 v1013 a

Efficient carbonylation of glycerol using urea with Zn-Co mixed metal oxide (MMO) catalyst has been achieved. Various methods of catalyst preparation were explored for glycerol carbonate (GC) synthesis. The optimized method of catalyst preparation was found to be co-precipitation (CP) with a Zn:Co ratio of 70:30, achieving 81% glycerol conversion with 97% GC selectivity. X-ray diffraction (XRD) studies revealed the formation of ZnO, Co-3 O-4, and spinel ZnCo2O4 phases. Thermal treatment given to the catalyst allows insertion of Zn cations into Co3O4 lattice forming ZnCo2O4 phase which was also evidenced in X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Herein, for the first time, reaction kinetics was studied to propose the rate equation, based on which a plausible reaction pathway is proposed involving two-site adsorption of glycerol (basic site) and urea (acidic site), which undergo carbonylation followed by cyclization into GC. A recycle study and hot filtration test have proven the reusability of the catalyst.

10aCarbonylation10acyclic carbonate10aGlycerol10akinetics10amixed metal oxide1 aKondawar, Sharda, E.1 aKasar, Gaytri, B.1 aKhatua, Angshuman, S.1 a uhttps://library.ncl.res.in/content/activity-performance-and-kinetics-glycerol-carbonylation-urea-over-zn-co-mixed-metal-oxide