La3+-SO2-4/TiO2催化合成衣康酸二丁酯

研究了固体超强酸La³⁺-SO^2-₄/TiO₂催化衣康酸与正丁醇合成衣康酸二丁酯的酯化反应，考察了催化剂种类，确定以La³⁺-SO^2-₄/TiO₂为催化剂，催化剂La³⁺-SO^2-₄/TiO₂的最佳焙烧温度为450 ℃。并考察反应物配比、催化剂用量和反应时间等因素对酯化反应的影响，确定最佳工艺条件：n（衣康酸）∶n（正丁醇）＝1∶3，催化剂用量为反应物总质量的4.5%，反应时间3.0 h。在该条件下，衣康酸转化率达95.7%，产物衣康酸二丁酯收率为93.3%。并对La³⁺-SO^2-₄/TiO₂的重复使用性能进行考察，结果表明，与La³⁺-SO^2-₄/TiO₂相比，La³⁺-SO^2-₄/TiO₂重复使用5次后，仍具有较高的催化活性，衣康酸转化率为92.3%，衣康酸二丁酯收率90.8%，说明稀土元素La的添加对于增加固体超强酸的寿命起了主要作用。

Synthesis of dibutyl itaconate catalyzed by La3+ -SO2-4 /TiO2 solid superacid

Synthesis of dibutyl itaconate using itaconic acid and butyl alcohol as raw materials and La3＋SO4^2-/TiO2 solid superacid as the catalyst was studied. The optimum calcination temperature of La3＋SO4^2-/TiO2 catalyst was 450 ℃. Effects of molar ratio of reactants, catalyst dosage, reaction time and repeated use of La3＋SO4^2-/TiO2 catalyst on esterification reaction were investigated. The results showed that itaeonic acid conversion of 95.7% and dibutyl itaconate yield of 93.3% were attained under optimum condition as follows ： n （ itaeonic acid） ： n （ butyl alcohol） = 1 ： 3, catalyst dosage 4.5% of total reactants mass, reaction time 3 h ; La3＋SO4^2-/TiO2 catalyst exhibited higher catalytic activity than that of S042-/TiO2 catalyst after using 5 times, and conversion of itaconic acid and yield of dibutyl itaconate over La3＋SO4^2-/TiO2catalyst were 92.3% and 90.8% prolonging La3＋SO4^2-/TiO2 catalyst life. , respectively; adding La had main influence on prolonging La3＋SO4^2-/TiO2 catalyst life.