硅胶负载磷钨酸催化剂上苯与1-十二烯烷基化

以硅胶为载体 ,用浸渍法制备了不同负载量的磷钨酸催化剂 ,通过X射线衍射 (XRD)、程序升温氨脱附 (NH3-TPD)以及低温N2 吸附技术表征了催化剂的物理化学性质 ,并且考察了催化剂在苯与 1-十二烯烷基化反应中的催化性能。结果表明 ,硅胶负载磷钨酸催化剂具有转化率高、选择性好等特点 ;通过改变催化剂预处理温度和杂多酸负载量 ,可有效地调整催化剂的反应性能 ;磷钨酸最佳负载量为 40 % (质量分数 ) ,催化剂最佳活化温度为 3 0 0℃ ,此时反应转化率为 71 4% ,2 -苯基十二烷的选择性为 41 9%。与HY沸石相比 ,硅胶负载磷钨酸催化剂具有更高的转化率、选择性和稳定性

Alkylation of Benzene with 1-Dodecene over Silica Gel Supported Phosphotungstic Acid Catalysts

phosphotungstic acid (PW) catalysts supported on silica gel with various PW loadings were prepared by the impregnation method,and characterized by X-ray diffraction,temperature programmed desorption of ammonia and nitrogen adsorption techniques.Their catalytic activity was measured by alkylation of benzene with 1-dodecene in a slurry reactor under atmospheric pressure.Silica gel supported 12-phosphotungstic acid catalysts were found to exhibit very high conversion of 1-dodecene and selectivity of 2-LAB,which could be adjusted by the pretreatment temperature of the catalyst and the PW loading.The catalyst with PW loading of 40% by mass and with a pretreatment temperature of 300 ℃ possessed the highest conversion of 1-dodecene at 71.4%,with high 2-LAB selectivity of 41.9%,which were much higher than those of HY zeolite.The catalytic activity has also been discussed in relation with the catalyst acidity and porous property.