文献类型：期刊文献

英文题名：Phosphotungstic acid immobilized on amino-functionalized TS-1 zeolite as a solid acid catalyst for the synthesis of tributyl citrate

作者：Li, Pei[1];Shi, Bianfang[1];Shen, Junyao[1];Cui, Ran[1];Guo, Wenze[1,2];Zhao, Ling[1];Xi, Zhenhao[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Minist Educ, Key Lab Smart Mfg Energy Chem Proc, Shanghai 200237, Peoples R China

年份：2024

卷号：70

起止页码：199

外文期刊名：CHINESE JOURNAL OF CHEMICAL ENGINEERING

收录：;EI(收录号：20242216183372);WOS:【SCI-EXPANDED(收录号:WOS:001248303800002)】；

基金：This work was financially supported by the National Natural Science Foundation of China (21978089) , the Program of Shanghai Academic/Technology Research Leader (21XD1433000) , and Key Research and Development Program of Xinjiang Uygur Autono- mous Region (2022B01032-1) .

语种：英文

外文关键词：Amino-functionalization; Phosphotungstic acid; Esterification; Tributyl citrate; TS-1 zeolite

摘要：The amino-functionalization of TS-1 zeolite followed by immobilization of phosphotungstic acid (HPW) was presented to prepare a strong solid acid catalyst for the synthesis of bio-based tributyl citrate from the esterification of citric acid and n-butanol. g-Aminopropyltriethoxysilane (APTES) was first grafted on the TS-1 zeolite via the condensation reactions with surface hydroxyl groups, and subsequently the HPW was immobilized via the reaction between the amino groups and the protons from HPW-forming strong ionic bonding. The Keggin structure of HPW and MFI topology of TS-1 zeolite were well maintained after the modifications. The amino-functionalization generated abundant uniformly distributed active sites on TS-1 for HPW immobilization, which promoted the dispersity, abundance, as well as the stability of the acid sites. The tetrahedrally coordinated framework titanium and non-framework titania behaved as weak Lewis acid sites, and the protons from the immobilized HPW acted as the moderate or strong Brensted acid sites. An optimized TBC yield of 96.2% (mol) with a conversion of -COOH of 98.1% (mol) was achieved at 150 degrees C for 6 h over the HPW immobilized on amino-functionalized TS-1. The catalyst exhibited good stability after four consecutive reaction runs, where the activity leveled off at still a relatively high level after somewhat deactivation possibly caused by the leaching of a small portion of weakly anchored APTES or HPW. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights reserved.