中孔分子筛上苯与1-十二烯烷基化合成十二烷基苯

在常压、50～70 ℃和苯∕1-十二烯摩尔比8:1条件下，利用间歇反应装置实验评价了MCM-22、0.5%磷改性MCM-22和1.5%磷改性MCM-22三种中孔分子筛对苯与1-十二烯烷基化合成十二烷基苯的催化性能，并结合NH3-TPD、XRD和BET表征结果，探讨了分子筛物理化学特性对其催化性能的影响。结果表明：（1）实验考察的三种分子筛均具有强酸和弱酸两种酸中心，适宜的强酸量对提高分子筛的催化活性和2位烷基化产物的选择性有利；（2）2位烷基化产物的选择性随分子筛中所含磷含量的增加而增加，但过高的磷含量将导致烯烃转化率的降低，因此控制适宜的磷改性用量是非常重要的；（3）0.5%磷改性MCM-22在所考察的三种分子筛中对十二烷基苯的合成具有更好的催化性能，其70℃下的烯烃转化率达到34%，2位产物选择性不低于60％。

Dodecylbenzene synthesis by the alkylation of benzene with 1-dodecene over mesoporous zeolites

The catalytic performance of MCM-22, and phosphorus-doped MCM-22(0.5%P) and MCM-22(1.5%P) mesoporous zeolites in the alkylation of benzene with 1-dodecene was experimentally evaluated using a batch reactor under the following conditions: 50℃-70 ℃, benzene/1-dodecene molar ratio 8 and atmospheric pressure. Combining these results with NH3-TPD, XRD and BET data, the influence of the physicochemical properties of the zeolites on their catalytic performance was investigated. The results showed: (1) all three zeolites possess both weak and strong acid sites, and the amount of strong acid sites is sufficient to increase both the zeolite activity and the selectivity to 2-linear alkylbenzenes (2-LAB); (2) the selectivity to 2-LAB was enhanced by increasing P content in the zeolite, but large P content resulted in decreased conversion of 1-dodecene, and therefore intermediate P content is most effective; (3) MCM-22(0.5%P) had the best catalytic performance in dodecylbenzene synthesis of the three zeolites investigated, with conversion of 1-dodecene reaching 34%, and selectivity of 2-LAB was above 60 % under 70oC.