| :It is turning into the focus of sustainable energy research to develop and utilize the biochemical resource, especially hydrolyzing biomass to gain platform chemicals. Comparing to the traditional catalysts, solid acid owns some certain advantages, which are easy to separate from products, able to recycle and reuse, and high in catalytic activity. Although there are great many researches focus on the kinetics of biomass hydrolysis, little concerns the heterogeneous nature of the reaction.We have prepared a kind of mesoporous molecular sieve SO42-/Ti-MCM-41by using CTAB as template, Na2SiO3as silicon source, and Ti(SO4)2as titanium source. It has been used as solid acid catalyst to catalyze cellulose and hemicellulose hydrolysis. Consequently, the kinetic models of reaction are also studied. For cellulose hydrolysis process, considering the heterogeneous nature of the reaction, a comprehensive kinetic model was proposed based on shrinking core model theory and polymer degradation mechanism theory. The results show that the predicted data obtained via the suggested model agree well with the experimental results. In addition, some kinetic data from the open reports were referred for the further model verification in this work, and the result shows that the model we proposed is quite universal. For hemicellulose hydrolysis, a similar kinetic model is proposed based on the polymer degradation mechanism theory. The activation energy data were referred from the open reports, and illustrate that the catalyst we prepared owns an excellent catalytic activity.Based on the biomass hydrolysis kinetic model we proposed, we investigated the cellulose hydrolysis, and simulated the effect of several process conditions in ideal condition of intermittent and continuous reaction, respectively. The optimum process condition to hydrolyze cellulose for5-HMF is obtained:The flow rate is0.0046L/min, the liquid-to-solid ratio of feeding is0.03-0.04, and the reaction temperature is473-483K. |
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