A sustainable process was explored for the preparation of 5-hydroxymethylfurfural(HMF) by catalytic degradation of the waste cotton stalk. Solid super-acid(SO_4^(2-)/ZrO_2) was used as an efficient catalyst for the de...A sustainable process was explored for the preparation of 5-hydroxymethylfurfural(HMF) by catalytic degradation of the waste cotton stalk. Solid super-acid(SO_4^(2-)/ZrO_2) was used as an efficient catalyst for the degradation of cotton stalk. Both decomposition experiments and kinetic study were conducted for the exploration of degradation condition and kinetics mechanism. The optimized experimental conditions are reaction temperature 503 K, reaction time 75 min and dosage of catalyst 30%(mass fraction) based on the decomposition experiments, under which a maximum yield of 27.2% for HMF could be achieved. Kinetic study was then carried out in the presence of SO_4^(2-)/ZrO_2. The theoretical results indicate that the activation energies for reducing sugar and HMF with catalyst are 96.71 k J/mol, 84.21 kJ/mol in the presence of SO_4^(2-)/ZrO_2, and they are 105.96 k J/mol and 119.37 k J/mol in the absence of SO_4^(2-)/ZrO_2.展开更多
Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% （w/v） solid. It was found that the best commercial cellulose enzyme was Cellic（R） CTec comparing to Accellerase 1000TM...Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% （w/v） solid. It was found that the best commercial cellulose enzyme was Cellic（R） CTec comparing to Accellerase 1000TM and Accelerase 1500TM. The Cellic（R） CTec gave the highest reducing sugar concentration and rice straw conversion. Moreover, when the hydrolysate obtained from hydrolysis using Cellic（R） CTec was fermented by Saccharomyces cerevisiae TISTR 5596, it would give the highest ethanol. In this study, the Cellic（R） CTec was used for fed-batch prehydrolysis prior to ethanol production by simultaneous saccharification and fermentation （SSF） way at 20% （w/v） solid loading. It could produce 35.76 g/L or 4.6% （v/v） of ethanol concentration and 83.67 L/ton dry matter （DM） of yield.展开更多
基金Project(2010DFA41440)supported by China-Japan International CooperationProject(2016TP1007)supported by the Hunan Provincial Science and Technology Plan,ChinaProject(21376269)supported by the National Natural Science Foundation of China
文摘A sustainable process was explored for the preparation of 5-hydroxymethylfurfural(HMF) by catalytic degradation of the waste cotton stalk. Solid super-acid(SO_4^(2-)/ZrO_2) was used as an efficient catalyst for the degradation of cotton stalk. Both decomposition experiments and kinetic study were conducted for the exploration of degradation condition and kinetics mechanism. The optimized experimental conditions are reaction temperature 503 K, reaction time 75 min and dosage of catalyst 30%(mass fraction) based on the decomposition experiments, under which a maximum yield of 27.2% for HMF could be achieved. Kinetic study was then carried out in the presence of SO_4^(2-)/ZrO_2. The theoretical results indicate that the activation energies for reducing sugar and HMF with catalyst are 96.71 k J/mol, 84.21 kJ/mol in the presence of SO_4^(2-)/ZrO_2, and they are 105.96 k J/mol and 119.37 k J/mol in the absence of SO_4^(2-)/ZrO_2.
文摘Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% （w/v） solid. It was found that the best commercial cellulose enzyme was Cellic（R） CTec comparing to Accellerase 1000TM and Accelerase 1500TM. The Cellic（R） CTec gave the highest reducing sugar concentration and rice straw conversion. Moreover, when the hydrolysate obtained from hydrolysis using Cellic（R） CTec was fermented by Saccharomyces cerevisiae TISTR 5596, it would give the highest ethanol. In this study, the Cellic（R） CTec was used for fed-batch prehydrolysis prior to ethanol production by simultaneous saccharification and fermentation （SSF） way at 20% （w/v） solid loading. It could produce 35.76 g/L or 4.6% （v/v） of ethanol concentration and 83.67 L/ton dry matter （DM） of yield.
