SO_4^(2-)/TiO_2-Al_2O_3催化合成季戊四醇四异硬脂酸酯

Synthesis of pentaerythritol tetraisostearate catalyzed by SO_4^(2-)/TiO_2-Al_2O_3

以自制SO42-/TiO2-Al2O3固体超强酸为催化剂,进行季戊四醇和异硬脂酸的酯化反应,合成了季戊四醇四异硬脂酸酯,考察了酸醇摩尔比、催化剂用量、反应温度、反应时间等条件对酯化反应的影响。确定了较优的合成条件:n(异硬脂酸)∶n(季戊四醇)=4.3∶1,催化剂用量为总反应物质量的0.060%,230℃回流反应10 h。用红外光谱对反应产物进行了表征,结果表明,SO42-/TiO2-Al2O3固体超强酸在季戊四醇四异硬脂酸酯合成反应中有较高的催化活性和高的反应选择性,酯化率达97%以上,且催化剂重复使用5次仍保持较高活性。

Using self-prepared SO42-/TiO2-Al2O3 solid superacid as catalyst,pentaerythritol and isostearic acid were esterified to synthesize pentaerythritol tetraisostearate.Effects of factors,such as molar ratio of isostearic acid to pentaerythritol,the dosage of catalyst,reaction temperature,reaction time on the results of esterification were investigated.The optimal conditions were determined as：n（isostearic acid）∶n（pentaerythritol）=4.3∶ 1,the dosage of the catalyst w=0.060% of total mass of the reactants,reaction time 10 h and reaction temperature 230 ℃.The reaction products were characterized by the FTIR.Results showed that SO42-/TiO2-Al2O3 solid superacid performs good catalytic activity with high reaction selectivity in the process of synthesis of pentaerythritol tetraisostearate.The esterifying conversion achieves more than 97%,and the catalyst could be repeatedly used for five times without significant declining of its catalytic activity.