【摘要】 以正丙醛、甲醛和液碱为主要原料,经羟醛缩合、Cannizzaro歧化反应制备三羟甲基乙烷,考察了缩合、歧化氧化反应条件。结果表明,最佳实验条件为:正丙醛∶甲醛∶液碱=1∶3.2∶1.05(物质的量比),缩合反应温度35℃左右,缩合反应时间6 h;岐化反应温度65℃,岐化反应时间2 h;反应转化率>90%。反应液采用溶剂法除盐、离子交换法除Na+、共沸除水、溶剂结晶、重结晶工艺处理,三羟甲基乙烷产品总收率>75%,产品纯度>95%。更多还原

【Abstract】 Trimethylolethane(TME) was synthesized from n-propylaldehyde,an aqueous solution of formaldehyde and an aqueous solution of sodium hydroxide through aldol condensation reaction and Cannizzaro reaction.Considering emphatically the aldol condensation reaction and the Cannizzaro reaction and the optimum reaction conditions were obtained:the condensation reaction temperature about 35 ℃,n(n-propylaldehyde) ∶n(formaldehyde) ∶n(sodium hydroxide)=1 ∶3.2 ∶1.05,the condensation reaction time 2 h;the Cannizzaro reaction temperature about 65 ℃,the conversion rate of TME >90%.The product were isolated from the crude reaction solution of TME by solvent extraction process desalination,ion-exchange,azeotropic dehydration,crystallization and recrystallization.The total yield of TME>75% and purity>95% under the optimum reaction condition.更多还原