粉煤灰复合硫酸亚铁固体酸的制备及其催化合成柠檬酸三丁酯

Preparation of Solid Acid from Coal Ash and Ferrous Sulfate and Catalytic Synthesis of Tributyl Citrate

研究了用粉煤灰与硫酸亚铁复合制备的固体酸催化剂替代浓硫酸,用于合成柠檬酸三丁酯。通过对不同条件下制备的催化剂筛选发现,在w(FeSO4)∶w(粉煤灰)∶w(CaO)=1∶4∶1、焙烧温度550℃、焙烧时间5h条件下制备的催化剂(FSF-2g)具有较高催化活性。还考察了酯化反应条件对酯化率的影响,结果表明,在原料酸醇摩尔比为1∶3.5、催化剂用量为2.0g(为反应物柠檬酸质量的12%)、反应温度100～120℃、反应时间3h、带水剂甲苯为5mL的条件下,酯化率可达98%。

A solid acid was prepared from coal ash and ferrous sulfate and used in synthesizing tributyl citrate instead of H2SO4 as catalyst. The catalyst FSF - 2g had high activity, prepared under conditions： w（FeSO4） ： w （ coal ash） ： w （CaO） = 1 ： 4 ： 1, roasting temperature 550 ℃, roasting time 5 h. The effects of reaction conditions on the esterification rate were investigated. The results showed that the esterification rate was 98 % in following conditions ： molar ratio of acid to alcohol 1 ： 3.5, amount of catalyst 2.0 g（ 12% based on citrate acid amount）, reaction temperature 100 - 120 ℃, reaction time 3 h, and water- carrying agent methylbenzene 5 mL.