Amirineni Srikanth - Academia.edu (original) (raw)
Uploads
Papers by Amirineni Srikanth
Applied Petrochemical Research, 2015
Vapor phase hydrogenolysis of glycerol was studied over Ru catalysts supported on TiO 2-ZrO 2 bin... more Vapor phase hydrogenolysis of glycerol was studied over Ru catalysts supported on TiO 2-ZrO 2 binary oxide. Ru catalysts with various ruthenium loadings from 1.0 to 6.0 wt% were prepared by deposition-precipitation method on the TiO 2-ZrO 2 mixed oxide support. These catalysts were characterized by X-ray diffraction, H 2 temperature-programmed reduction, NH 3 temperatureprogrammed desorption, transmission electron microscopy, BET surface area, XPS and CO chemisorption measurements. The catalysts exhibited superior performance for the vapor phase hydrogenolysis of glycerol at moderate temperature and atmospheric pressure. The mixed oxide support plays a significant role in improving the catalytic activity for the production of propanediols. The glycerol conversion and the selectivity of various products depend on the catalyst preparation method and also on the Ru content. The influence of acidity of the catalyst and its correlation to the catalytic performance (selectivity and conversion) has been studied. The weak and strong acidic sites of the catalysts measured by NH 3-TPD play a key role in selective formation of 1,2-propanediol and 1,3propanediol. XRD, TEM, XPS and CO chemisorption studies revealed that ruthenium was well dispersed on TiO 2-ZrO 2 which further contributed to the superior catalytic activity for glycerol hydrogenolysis.
Journal of Chemical Sciences, Mar 1, 2014
A series of vanadium-substituted phosphomolybdic acid (HPA) catalysts supported on zirconia were ... more A series of vanadium-substituted phosphomolybdic acid (HPA) catalysts supported on zirconia were prepared by impregnation method with varying the HPA active phase content from 10 to 50 wt% on the support. The calcined catalysts were characterized by X-ray diffraction, Raman spectroscopy, temperatureprogrammed desorption of NH 3 , FT-IR spectra of pyridine adsorption and surface area measurements. XRD results suggest that the active phase of heteropolyacid is present in a highly dispersed state at lower loadings and as a crystalline phase at higher HPA loadings and these findings are well-supported by the results of FT-IR and Raman spectra. Calcination of the samples did not affect the Keggin ion structure of HPA. The ammonia TPD results suggest that acidity of the catalysts was found to increase with increase of HPA loading up to 40 wt% and decreases at higher loadings. FT-IR spectra of pyridine adsorption show that the Brønsted acidic sites increase with increase of HPA loadings up to 40 wt% catalyst. However, Lewis acid sites decrease with increase of HPA loading. Catalytic properties were evaluated during vapour phase dehydration of glycerol to acrolein. The catalyst with 40 wt% HPA has exhibited excellent selectivity towards acrolein formation with complete conversion of glycerol at 225 • C under atmospheric pressure. Catalytic performances during dehydration of glycerol are well-correlated with acidity of the catalysts. Keywords. H 4 PMo 11 VO 40 /ZrO 2 ; acidity; Raman; glycerol dehydration; acrolein.
Applied Petrochemical Research, 2015
Vapor phase hydrogenolysis of glycerol was studied over Ru catalysts supported on TiO 2-ZrO 2 bin... more Vapor phase hydrogenolysis of glycerol was studied over Ru catalysts supported on TiO 2-ZrO 2 binary oxide. Ru catalysts with various ruthenium loadings from 1.0 to 6.0 wt% were prepared by deposition-precipitation method on the TiO 2-ZrO 2 mixed oxide support. These catalysts were characterized by X-ray diffraction, H 2 temperature-programmed reduction, NH 3 temperatureprogrammed desorption, transmission electron microscopy, BET surface area, XPS and CO chemisorption measurements. The catalysts exhibited superior performance for the vapor phase hydrogenolysis of glycerol at moderate temperature and atmospheric pressure. The mixed oxide support plays a significant role in improving the catalytic activity for the production of propanediols. The glycerol conversion and the selectivity of various products depend on the catalyst preparation method and also on the Ru content. The influence of acidity of the catalyst and its correlation to the catalytic performance (selectivity and conversion) has been studied. The weak and strong acidic sites of the catalysts measured by NH 3-TPD play a key role in selective formation of 1,2-propanediol and 1,3propanediol. XRD, TEM, XPS and CO chemisorption studies revealed that ruthenium was well dispersed on TiO 2-ZrO 2 which further contributed to the superior catalytic activity for glycerol hydrogenolysis.
Journal of Chemical Sciences, Mar 1, 2014
A series of vanadium-substituted phosphomolybdic acid (HPA) catalysts supported on zirconia were ... more A series of vanadium-substituted phosphomolybdic acid (HPA) catalysts supported on zirconia were prepared by impregnation method with varying the HPA active phase content from 10 to 50 wt% on the support. The calcined catalysts were characterized by X-ray diffraction, Raman spectroscopy, temperatureprogrammed desorption of NH 3 , FT-IR spectra of pyridine adsorption and surface area measurements. XRD results suggest that the active phase of heteropolyacid is present in a highly dispersed state at lower loadings and as a crystalline phase at higher HPA loadings and these findings are well-supported by the results of FT-IR and Raman spectra. Calcination of the samples did not affect the Keggin ion structure of HPA. The ammonia TPD results suggest that acidity of the catalysts was found to increase with increase of HPA loading up to 40 wt% and decreases at higher loadings. FT-IR spectra of pyridine adsorption show that the Brønsted acidic sites increase with increase of HPA loadings up to 40 wt% catalyst. However, Lewis acid sites decrease with increase of HPA loading. Catalytic properties were evaluated during vapour phase dehydration of glycerol to acrolein. The catalyst with 40 wt% HPA has exhibited excellent selectivity towards acrolein formation with complete conversion of glycerol at 225 • C under atmospheric pressure. Catalytic performances during dehydration of glycerol are well-correlated with acidity of the catalysts. Keywords. H 4 PMo 11 VO 40 /ZrO 2 ; acidity; Raman; glycerol dehydration; acrolein.