摘要
比较了Br nsted酸，包括硫酸、磷酸、对甲苯磺酸，催化季戊四醇与脂肪酸的酯化反应行为，结果表明，硫酸催化酯化反应速率最快，能有效催化不同类型的新戊基多元醇与脂肪酸的酯化反应，羟基转化率达到98％以上。研究了硫酸催化条件下新戊基多元醇脂肪酸酯化反应动力学行为，结果表明，酯化反应速率明显受到空间位阻效应的影响，提高催化剂用量和升高反应温度，能有效提高酯化速率，催化剂用量0．25％～0．50％、反应温度185～190℃为适宜的控制范围；硫酸催化酯化反应过程中，存存明硅的非酯化催化反应，不能得到低硫含量的酯。硫酸催化酯化反应机理遵循“中间产物为烷基化硫酸”模型。
Esterification behaviors of neo - polyhydric alcohols with fatty acids catalyzed by Br nsted acid catalysts, including sulfuric acid, phosphoric acid, p -toluenesulfonic acid, were compared. Results showed that sulfuric acid is the most effective catalyst and can catalyze different kinds of esterification reaction of neo - polyhydric alcohols with fatty acids. And - OH translation ratio of neo - polyhydric alcohols can reach over 98%. Kinetic reaction behavior of neo - polyhydric alcohols with fatty acids catalyzed by sulfuric acid was studied. Results showed that both - OH translation rate and reaction rate are affected by stereo- hindrance, and reaction rate can be improved effectively with increasing catalyst content and reaction temperature. 0.25% -0.50% catalyst content and 185 -190 ℃ reaction temperature are the appropriate range. It was found that inherent performance of neo - polyhydric alcohol ester is not affected by sulfuric acid, but the processing performance is otherwise. Polyester with low sulphur content cannot be obtained owing to no esterification catalyzing, and this showed that esterification reaction mechanism follows the model of alkylsulfuric intermediate.
出处
《润滑油》
CAS
2009年第1期42-47,共6页
Lubricating Oil
关键词
硫酸
催化剂
新戊基多元醇
脂肪酸
酯化反应
sulfuric acid
catalyst
neo - polyhydric alcohol
fatty acid
esterification reaction
