Cr-MCM-41分子筛的合成、表征及其催化性能

Synthesis, characterization and catalytic properties of Cr-MCM-41 molecular sieves

合成了一系列掺杂Cr的MCM 41分子筛,并用XRD,IR和EXAFS等手段表征了催化剂.实验结果表明,一部分Cr离子进入到MCM 41骨架,另一部分Cr离子以其他Cr化合物形式存在且这部分铬可通过NH4Ac溶液洗去.Cr MCM 41和Cr MCM 41 t催化剂在十八醇选择氧化反应的几个循环中表现了稳定的十八醇转化率和十八酸选择性.

A series of Cr-containing MCM-41 molecular sieves has been synthesized and characterized by XRD, IR and Extend X-ray Absorption Fine Structure(EXAFS) techniques. It has been shown that a certain amount of chromium ions has been incorporated into the framework of MCM-41 and the rest part of the contained Cr ions still existed as other types of Cr-containing compounds, which can be washed off by a NH_4Ac solution. The (octadecan-)1-ol conversion and (octadecanoic) acid selectivity are not decreased after Cr-MCM-41 and Cr-MCM-41-t catalysts have been repeatedly used for the selective oxidation of octadecan-1-ol to octadecanoic acid.