Kinetics of the epoxidation of soybean oil with H2O2 catalyzed by phosphotungstic heteropoly acid in the presence of polyethylene glycol
Kinetics of the epoxidation of soybean oil with H2O2 catalyzed by phosphotungstic heteropoly acid in the presence of polyethylene glycol
复制标题
聚乙二醇存在下磷钨杂多酸催化 H2O2 环氧化大豆油的动力学
DOI：
10.1002/ejlt.201400614
复制
发表时间：
2015-08-01
影响因子：
2.7
通讯作者：
Jing, Lu
中科院分区：
文献类型：
--
作者：
Cheng, Weiwei;Liu, Guoqin;Jing, Lu
本文研究了在40、50、60和70 ℃下，以磷钨杂多酸[-C5 H5 N（CH 2）（15）CH 3]（3）[PW 4 O 16]（PHA）为相转移催化剂，聚乙二醇（PEG）为界面剂，大豆油为原料，H2 O2（30%w/w）原位环氧化反应的动力学。假设环氧化反应发生在假均相催化体系中，环氧环断裂副反应可以忽略，结果表明PEG存在下大豆油的环氧化反应对双键浓度为二级反应，对H2 O2浓度为一级反应。相应的表观活化能（42.12kJ/mol）低于PHA单独存在时的表观活化能（49.23kJ/mol），表明PEG可以降低大豆油环氧化反应的活化能，加速大豆油环氧化反应。实际应用：为了解决大豆油过氧化产率低和过酸环氧化大豆油对环境造成污染的问题，迫切需要一种环境友好的催化剂。磷钨杂多酸相转移催化剂和聚乙二醇提高了大豆油环氧化反应的转化率和选择性，提高了其生产效率。
In this work, the kinetics of in situ epoxidation of soybean oil with H2O2 (30% w/w), catalyzed by phosphotungstic heteropoly acid [-C5H5N(CH2)(15)CH3](3)[PW4O16] (PHA) phase transfer catalyst and polyethylene glycol (PEG) as interfacial agent in dichloroethane, were investigated at 40, 50, 60, and 70 degrees C. Assuming that the epoxidation reaction occurred in the pseudo-homogeneous catalytic system and the side reaction of epoxy ring cleavage was negligible, the results appeared that the epoxidation reaction of soybean oil in the presence of PEG was a second-order with respect to double bond concentration and a first-order to the H2O2 concentration. The corresponding apparent activation energy (42.12kJ/mol) was lower than that of PHA alone (49.23kJ/mol), indicating that PEG could decrease the activation energy and speed up the epoxidation reaction of soybean oil. Practical applications: An environmentally friendly catalyst is eagerly needed to produce peroxided soybean oil for low yield and to prevent polluting the environment through the epoxidation of soybean oil with peracid. Phosphotungstic heteropoly acid phase transfer catalyst and polyethylene glycol improve the conversion and selectivity of the epoxidation reaction of soybean oil, and enhance its production efficiency.