Biomass-derived carbohydrates exploited toward the synthesis of alkyl levulinates is very promising, but still limited by the applicable catalyst. In this study, novel metal/Si-pillared montmorillonite supported phosphotungstic acid catalysts (SG-HPW-XSiMt-y, where X = La³⁺, Ce³⁺, Er³⁺, Cu²⁺, Al³⁺, Ti⁴⁺, Zr⁴⁺) were synthesized by sol-gel method. The catalytic performance of SG-HPW-XSiMt-y were comprehensively studied for glucose methanolysis to methyl levulinate (ML), focusing on the effects of metal acidity, HPW contents and reaction conditions. The appropriate Lewis acidity of metal ions effectively facilitated the isomerization of glucose/methyl-glucoside to fructose/methyl-fructoside; the strong Brønsted acidity of incorporated HPW was capable of suppressing the side reactions; and the large specific surface area and hierarchical pores of the mesoporous structure allow the reaction to take place both on surface and inside the porous framework. Among these as-synthesized catalysts, the SG-HPW-ZrSiMt-20 showed the most superior activity and achieved 65.8% yield of ML from glucose at 170 °C for 4 h. Alternative biomass-derived carbohydrates, including fructose, sucrose and cellobiose, also gave excellent ML yields under such catalytic system. The SG-HPW-ZrSiMt-20 had impressively stable reusability with merely loss of catalytic activity after eight cycles, owing to the uniform dispersion and stable bonding of HPW with ZrSiMt support. Generally, this catalyst system realizes an efficient and sustainable conversion of biomass-derived carbohydrates to ML production.

用于合成乙酰丙酸烷基酯的生物质衍生碳水化合物非常有前途，但仍受适用催化剂的限制。在这项研究中，新型金属/硅柱撑蒙脱石负载的磷钨酸催化剂（SG-HPW-XSiMt-y，其中 X = La ³⁺、Ce ³⁺、Er ³⁺、Cu ²⁺、Al ³⁺、Ti ⁴⁺ , 锆⁴⁺) 是通过溶胶-凝胶法合成的。SG-HPW-XSiMt-y 对葡萄糖甲醇分解制备乙酰丙酸甲酯 (ML) 的催化性能进行了综合研究，重点是金属酸度、HPW 含量和反应条件的影响。金属离子适当的路易斯酸度有效地促进了葡萄糖/甲基-葡糖苷异构化为果糖/甲基-果糖苷；掺入的 HPW 的强布朗斯台德酸性能够抑制副反应；介孔结构的大比表面积和分级孔允许反应在多孔框架的表面和内部发生。在这些合成的催化剂中，SG-HPW-ZrSiMt-20 表现出最优异的活性，在 170°C 下 4 小时从葡萄糖中获得 65.8% 的 ML。替代生物质衍生的碳水化合物，包括果糖、蔗糖和纤维二糖，在这种催化体系下也能获得极好的 ML 产率。由于 HPW 与 ZrSiMt 载体的均匀分散和稳定结合，SG-HPW-ZrSiMt-20 具有令人印象深刻的稳定可重复使用性，仅在八次循环后失去催化活性。通常，该催化剂系统实现了生物质衍生碳水化合物向 ML 生产的高效和可持续转化。