文献类型：期刊文献

英文题名：Mechanistic insights into Ti/SiO2-catalyzed gas-phase synthesis of glycolide from methyl glycolate

作者：Zhang, Dai[1,2];Zhu, Hang[1,2];Xu, Xiaofeng[3];Cao, Yueqiang[1,2];Li, Wei[2];Zhou, Jinghong[1,2,3];Zhou, Xinggui[1,2]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn & Low Carbon Technol, 130 Meilong Rd, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem Engn, Shanghai, Peoples R China;[3]East China Univ Sci & Technol, Sch Resources & Environm Engn, Shanghai, Peoples R China

年份：2026

外文期刊名：AICHE JOURNAL

收录：;EI(收录号：20260620033412);WOS:【SCI-EXPANDED(收录号:WOS:001677361100001)】；

基金：National Natural Science Foundation of China, Grant/Award Numbers: 22478106, 22178102, 22332003; Shanghai Rising-Star Program, Grant/Award Number: 23QA1401900; China Association for Science and Technology, Grant/Award Number: 2023QNRC001; National Innovation Center par Excellence (NICE)

语种：英文

外文关键词：glycolide; methyl glycolate; reaction mechanism; support effects; Ti/SiO2 catalysts

摘要：Gas-phase catalytic synthesis of glycolide (GL) from methyl glycolate (MG) offers a promising route for sustainable production of polyglycolic acid, yet suffers from unfavorable catalytic performances due to limited mechanistic understandings. Here, a series of Ti/SiO2 catalysts supported on mesoporous materials with distinct pore structures were synthesized to elucidate the structure-performance-mechanism relationship. Among them, Ti/KIT-6 exhibited the highest MG conversion and GL yield, attributed to its large pore size, three-dimensional interconnected mesostructure, and well-dispersed tetrahedral Ti(IV) species. Comprehensive structure characterizations and mechanistic studies establish a linear correlation for MG conversion rate and GL formation rate with the tetrahedral Ti(IV) content, pointing to Ti(IV) as the intrinsic active sites. Further combining with temperature-programmed and in situ spectroscopy experiments, a possible reaction mechanism is proposed for MG-to-GL on the active site. This study provides mechanistic insights to guide design of Ti-based catalysts for gas-phase ester cyclization reactions.