编号 020028001
推送时间 20210301
研究领域 林产化工
年份 2021
类型 期刊
语种 英语
标题 Epoxidation of Tall Oil Catalyzed by an Ion Exchange Resin under Conventional Heating and Microwave Irradiation
来源期刊 Industrial & Engineering Chemistry Research
期 第280期
发表时间 20200512
关键词 Tall oil fatty acids; Conventional Heating; Microwave Irradiation;
摘要 Tall oil fatty acids (TOFA) are a byproduct from the Kraft pulping process, and they represent a renewable and inexpensive alternative with high potential as a renewable feedstock. Epoxidized TOFA have great potential as chemical intermediates. Epoxidation of oleic acid, TOFA, and distilled tall oil (DTO) was conducted in an isothermal batch reactor with in situ-formed peracetic acid using hydrogen peroxide as the reactant and acetic acid as the reaction carrier. Amberlite IR-120 was used as the solid heterogeneous catalyst. The catalyst loading effect, the reactant ratios, the reaction temperature (40–70 °C), and the influence of microwave irradiation on epoxidation and ring opening were studied. The application of microwave irradiation resulted in an improvement of the epoxidation rate in the absence of the catalyst. Lower product yields were obtained for the epoxidation of DTO than for TOFA because of the higher viscosity and high content of rosin acids which presumably promoted ring opening reactions. At higher temperatures, the selectivity to oxirane decayed due to ring opening. Titration analysis and NMR analysis confirmed that microwave irradiation induces the ring opening reactions for TOFA epoxidation, and it accelerates this process for DTO. The rapid nature of the microwave heating might have unchained a series of ring opening reactions between neighboring oxirane groups and with the nucleophilic agents in the reaction mixture.
服务人员 尚玮姣
PDF文件 浏览全文