分子筛担载硼酸镧催化脂肪醇乙氧基化反应

Ethoxylation of fatty alcohol using lanthanum borate supported on Y-molecular sieve as catalyst

通过微波加热的方法,将质量分数为20%的硼酸镧分散在Y分子筛上,得到负载型La2(B2O7)3-NaY分子筛催化剂。La2(B2O7)3-NaY用于催化正辛醇乙氧基化反应。结果表明:La2(B2O7)3-NaY的催化活性与La2(B2O7)3及Y分子筛相比均有较大程度的提高。正交实验结果表明:La2(B2O7)3-NaY催化剂的用量为正辛醇质量的5%,反应温度为140℃,初始压力为0 4MPa～0 5MPa,当环氧乙烷(EO)平均加成数为2 2时,EO加成数为1、2和3的3种组分之和占产物中醇醚总质量的73 2%,正辛醇转化率为85%,产品的分子质量分布指数E=2888,具有较好的窄分布效果,且催化剂可重复使用,重复使用3次催化速率没有改变。

With a dosage of 20 %(mass),lanthanum borate [La_2(B_2O_7)_3] was dispersed on Y-molecular sieve and after heating in a microwave oven,a loaded type catalyst,La_2(B_2O_7)_3-NaY was prepared for the ethoxylation of n-octanol.Evaluation of activity of the catalyst showed that its performance is improved significantly as compared with La_2(B_20_7)_3 and Y-molecular sieve used alone at same conditions.Results from experiments in accordance with orthogonal design,under the conditions that the dosage of catalyst at (5 %)(mass)of the n-octanol,at temperature of (140 ℃),at initial pressure of (0.4 MPa)～(0.5 MPa),when the average EO adduction of 2.2 moles,the total content of components of 1,2,and 3 mole EO adducts achieves (73.2 %)(mass).The conversion of n-octanol achieves (85 %) and the molar mass distribution index E achieves (2 888).Obviously,the catalyst provides a good narrow product distribution.The catalyst can be used repeatedly for three times without declining of the reaction rate.