Directed hydrogenolysis of "cellulose-to-ethylene glycol" using a Ni-WO based catalyst
Tong Su1, Daguo Wu1, Xinghua Zhang1
1Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University Nanjing 210096 People's Republic of China zhuangxz@seu.edu.cn.
Abstract:
Biomass is an important renewable resource in nature, and cellulose is a crucial component within it. The chemically directed conversion of cellulose into ethylene glycol offers a green alternative to traditional petroleum-based production methods. In this study, a multifunctional Ni-WO /SAPO-11 catalyst was designed. By optimizing the processing parameters of catalysts and the reaction conditions of them, it was demonstrated that this catalyst could efficiently catalyze cellulose into alcohol products through a series of tandem reactions such as hydrolysis, retro-aldol condensation, and hydrogenation under relatively mild conditions. The yield of ethylene glycol climbed from 4% (at 180 °C) to 66.6% (at 240 °C) with the increase of reaction temperature. Characterization (XPS, TEM, TPD/TPR) revealed that a reduction temperature of 500 °C maximized Brønsted acidity and W5+/W6+ ratios, enhancing C-C cleavage efficiency. Further increases in the reduction temperature would weaken the Brønsted acid on the surface of SAPO-11, but its surface area would also increase (mainly in the form of mesopores). The uniformly dispersed elemental tungsten could form new acidic sites on the catalyst surface; in combination with active Ni0, this high-temperature reduced catalyst could achieve the direct hydrogenolysis of cellulose to produce ethylene glycol, benefiting the efficient utilization of lignocellulosic biomass in the future.
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