固载型杂多酸(盐)-桥键嵌入型离子液体合成新方法及其对苯甲醇催化氧化作用研究

A Novel Approach for the Synthesis of Polyoxometalate-based Bridged Ionic Complexes Immobilized in Mesoporous Silicas Via One-pot Procedure and Research for Alcohol Oxidations

本文采用了一种新的合成方法----一步法合成固载型杂多酸(盐)-双硅烷型(桥键嵌入型)离子液体,并对合成的催化剂进行XRD,低温N2吸附-脱附,FT-IR等一系列表征,用于催化苯甲醇的绿色选择性氧化反应,得到了88%的转化率和>99%的选择性,催化剂重复使用5次,催化活性未见明显降低。为比较不同的合成方法及离子液体在介孔材料中不同的位置所得到的催化剂的物理化学性质、催化活性等方面的差异,我们又采用传统的多步法(后嫁接法)及一步单硅烷法合成了2种催化剂作为对照,结束显示出了一步双硅烷法合成催化剂的优势所在。

In this paper, a novel approach for the synthesis of fabrication 12-tungstophosphoric acid-（dihydro）imidazolium cation ionic complexes immobilized into SBA-15 mesoporous silicas via one-pot procedure was introduced. The obtained materials were well characterized by a series of means such as XRD, nitrogen adsorption-desorption and so on. The catalyst showed outstanding catalytic performance（88% con. and 99% sele.） and satisfactory reusability（5times） in green selective alcohol oxidation. In order to investigate the influence on catalytic performance of two main factors： the location of the（dihydro）imidazolium cations in the mesostrucures as well as different synthetic route, two other catalysts were also been prepared. Ultimately, the catalyst with bridged ionic complexes synthesized via one pot procedure displayed highest TOF among the three catalysts.