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Papers by NARENDRA KUMAR
Topics in Catalysis, 2013
In this work, ionic liquid (IL) modified H-Beta zeolites were prepared and the physicochemical pr... more In this work, ionic liquid (IL) modified H-Beta zeolites were prepared and the physicochemical properties of the catalysts were investigated. IL modified zeolites were applied in 5-hydroxymethylfurfural (HMF) etherification to tert-butoxymethylfurfural (tBMF) which is a potential (bio)diesel component. The best catalyst, IL-H-Beta-25, yielded at BMF selectivity of 76 % corresponding to a HMF conversion of 46 %.
Journal of Molecular Catalysis A: Chemical, 2014
ABSTRACT The utilization of oil-cake waste (OCW) derived catalysts in biodiesel production was de... more ABSTRACT The utilization of oil-cake waste (OCW) derived catalysts in biodiesel production was demonstrated. The sulfonated carbon materials were utilized as catalysts for pretreatment of acid oils (oils containing 8.17-43.73 wt% of free fatty acids). The catalysts could be used to convert free fatty acids (FFA) present in acid oils into corresponding methyl esters within 6-8 h at 80 °C, thus reducing the FFA content to desirable levels below 2wt%. The esterification activity was found to be dependent on the initial FFA concentration found in the acid oil as well as methanol-to-oil molar ratio. High methanol-to-oil molar ratios and the presence of higher initial FFA concentrations resulted in enhanced esterification rates. Acid oil containing 43.7 wt% FFA was easily converted into mixtures containing up to 71% methyl esters (FAME). The reported catalyst was successfully recycled in five consecutive experiments and exhibited high thermal stability. Most importantly, the catalytic activity of the solid acid was found to outperform homogeneous case when equivalent amount of H2SO4 under similar conditions was applied. Therefore, the OCW derived sulfonated carbon catalyst reported herein could be used as a potential substitute for corrosive, concentrated H2SO4 currently employed for acid oil pretreatment.
Catalysis Today, 2005
Aluminium sulphate, sodium aluminate, aluminium oxide and pseudo-boehmite were used as sources of... more Aluminium sulphate, sodium aluminate, aluminium oxide and pseudo-boehmite were used as sources of aluminium in the synthesis of SAPO-5. The samples were characterized using XRD, SEM, XRF, FTIR and nitrogen adsorption. The formation of SAPO-5 phase, morphology, surface area and catalytic properties were found to be influenced by the source of aluminium used in the synthesis. The sample synthesized using
Applied Catalysis A: General, 2007
Thermal and catalytic oligomerisation of technical grade linoleic acid was investigated under arg... more Thermal and catalytic oligomerisation of technical grade linoleic acid was investigated under argon atmosphere at 280 8C. The most efficient catalyst was H-MCM-41 followed by H-Beta 75. Several types of products, such as cyclic and aromatic compounds were formed indicating a complex reaction network for catalytic oligomerisation of fatty acids.
Topics in Catalysis, 2013
In this work, ionic liquid (IL) modified H-Beta zeolites were prepared and the physicochemical pr... more In this work, ionic liquid (IL) modified H-Beta zeolites were prepared and the physicochemical properties of the catalysts were investigated. IL modified zeolites were applied in 5-hydroxymethylfurfural (HMF) etherification to tert-butoxymethylfurfural (tBMF) which is a potential (bio)diesel component. The best catalyst, IL-H-Beta-25, yielded at BMF selectivity of 76 % corresponding to a HMF conversion of 46 %.
Journal of Molecular Catalysis A: Chemical, 2014
ABSTRACT The utilization of oil-cake waste (OCW) derived catalysts in biodiesel production was de... more ABSTRACT The utilization of oil-cake waste (OCW) derived catalysts in biodiesel production was demonstrated. The sulfonated carbon materials were utilized as catalysts for pretreatment of acid oils (oils containing 8.17-43.73 wt% of free fatty acids). The catalysts could be used to convert free fatty acids (FFA) present in acid oils into corresponding methyl esters within 6-8 h at 80 °C, thus reducing the FFA content to desirable levels below 2wt%. The esterification activity was found to be dependent on the initial FFA concentration found in the acid oil as well as methanol-to-oil molar ratio. High methanol-to-oil molar ratios and the presence of higher initial FFA concentrations resulted in enhanced esterification rates. Acid oil containing 43.7 wt% FFA was easily converted into mixtures containing up to 71% methyl esters (FAME). The reported catalyst was successfully recycled in five consecutive experiments and exhibited high thermal stability. Most importantly, the catalytic activity of the solid acid was found to outperform homogeneous case when equivalent amount of H2SO4 under similar conditions was applied. Therefore, the OCW derived sulfonated carbon catalyst reported herein could be used as a potential substitute for corrosive, concentrated H2SO4 currently employed for acid oil pretreatment.
Catalysis Today, 2005
Aluminium sulphate, sodium aluminate, aluminium oxide and pseudo-boehmite were used as sources of... more Aluminium sulphate, sodium aluminate, aluminium oxide and pseudo-boehmite were used as sources of aluminium in the synthesis of SAPO-5. The samples were characterized using XRD, SEM, XRF, FTIR and nitrogen adsorption. The formation of SAPO-5 phase, morphology, surface area and catalytic properties were found to be influenced by the source of aluminium used in the synthesis. The sample synthesized using
Applied Catalysis A: General, 2007
Thermal and catalytic oligomerisation of technical grade linoleic acid was investigated under arg... more Thermal and catalytic oligomerisation of technical grade linoleic acid was investigated under argon atmosphere at 280 8C. The most efficient catalyst was H-MCM-41 followed by H-Beta 75. Several types of products, such as cyclic and aromatic compounds were formed indicating a complex reaction network for catalytic oligomerisation of fatty acids.