Nafion功能化介孔催化剂上苯甲醚/苯甲酰氯酰基化反应研究

Catalytic Acylation of Anisole and Benzoyl Chloride over Nafion Functionalized Mesoporous Catalysts

苯甲醚/苯甲酰氯的酰基化产物4-甲氧基二苯甲酮是多种精细化工产品的重要中间体.本工作主要介绍了Nafion负载型SBA-15,SBA-16及Me-SBA-15介孔超强酸催化剂的制备及其在苯甲醚/苯甲酰氯酰基化反应中的应用.实验结果表明,单位时间单位Nafion活性位上的苯甲酰氯转化数高于传统HBeta沸石和硫酸氧化锆,且载量的增加能显著提高酰基化催化性能.甲基修饰的Me-SBA-15介孔材料明显改善了催化剂表面的疏水性能,有效减缓了多聚芳烃副产物的生成,反应的转化率得到大幅提高.相对一维孔道结构的介孔SBA-15而言,三维笼状结构的SBA-16对反应物及产物分子具有更好的扩散性能,该结构优势由酰基化反应的高初始活性得以充分体现.在整个反应过程中,该类催化剂对4-甲氧基二苯甲酮具有专一的选择性.

Acylation reaction of anisole and benzoyl chloride produces 4-methoxybenzophenone which is an important intermediate for producing fine chemicals.In this work,Nafion impregnated SBA-15,SBA-16 and methyl-modified Me-SBA-15 catalysts were systematically synthesized and studied in this reaction.The results showed that the turnover frequencies over Nafion were higher than those over HBeta and sulfated zirconia and that the catalytic activity increased remarkably with the increasing of Nafion loading.The hydrophobicity modification of pore surface of SBA-15 promoted the conversion rate while reducing the polyaromatic byproducts.Nafion/SBA-16 is superior to Nafion/SBA-15 in molecular diffusion owning to its three-dimensional cubic structure,which was clearly shown in the initial activity.Selectivity of 4-methoxybenzophenone was favored during the reaction process.