摘要
研究了85%(w)甲醛溶液(简称浓甲醛)与甲缩醛(DMM)在阳离子交换树脂催化下合成聚甲氧基二甲醚(PODEn,n表示聚合度)的过程。采用FTIR、SEM和压汞法对催化剂进行了表征,考察了不同催化剂、反应温度、浓甲醛与DMM质量比和反应时间对甲醛转化率和目标产物PODE2-8选择性的影响。实验结果表明,4种阳离子交换树脂催化剂的酸类型为L酸,酸性越强,越有利于合成PODEn;催化剂具有过渡孔至大孔连续分布的孔结构有利于链增长反应发生。最佳反应条件为:3#催化剂、反应温度55℃、压力0.6 MPa、浓甲醛与DMM的质量比为1∶3、反应时间40 min。在此条件下,甲醛转化率为61.22%,PODE(2-80选择性为47.05%。
The synthesis of polymethoxydimethyl ether(PODEn,n denotes degree of polymerization) from 85%(w) formaldehyde and dimethoxymethane(DMM) reaction system catalyzed by cation exchange resin was studied. The catalyst was characterized by FTIR,SEM and mercury intrusion test. The effects of different catalyst,reaction temperature,mass ratio of 85% concentrated formaldehyde to DMM,and reaction time on conversion of formaldehyde and selectivity to the target product PODE2-8 were investigated. The results showed that the acid type of four cation exchange resin catalysts was Lacid,and the strong acidity of L acid was beneficial to the synthesis of PODEn. The catalyst,which had a pore structure with continuous distribution from transition pores to macropores,was favorable for chain growth reaction. The optimum reaction conditions were as follows:3# catalyst,55 ℃,0.6 MPa,mass ratio of 85%(w) formaldehyde to DMM being 1∶3,40 min. Under these conditions,the formaldehyde conversion was 61.22%,and the PODE2-8 selectivity was 47.05%.
作者
吴艳
王雪岭
梁旭
Wu Yan;Wang Xueling;Liang Xu(Research Institute of Coal Chemistry,China Coal Research Institute,Beijing 100013,China;State Key Laboratory of Coal Mining and Clean Utilization(China Coal Research Institute),Beijing 100013,China;National Energy Technology&Equipment Laboratory of Coal Utilization and Emission Control,Beijing 100013,China;Jiangsu Dalton Chemical Technology Co.,Ltd.,Wuxi Jiangsu 214000,China)
出处
《石油化工》
CAS
CSCD
北大核心
2020年第4期333-340,共8页
Petrochemical Technology
基金
国家重点研发计划资助项目(2018YFB0604804)。
关键词
聚甲氧基二甲醚
阳离子交换树脂
高浓度甲醛
甲缩醛
polymethoxydimethyl ether
cation exchange resin
85%concentrated formaldehyde
dimethoxymethane