Fabrication of hierarchical channel wall in Al-MCM-41 mesoporous materials to promote the efficiency of copper modifier

摘要

A new route to promote the efficiency of copper species in the Al-containing MCM-41, by anchoring the copper species into the artificial defects on the channel wall, was proposed and validated in this article. These artificial defects in Al-MCM-41 were fabricated by acid leach of framework alumina, and three different loading methods, dry impregnation and grinding as well as microwave irradiation methods were utilized to disperse the copper oxide of 0.6 wt.% on the mesoporous support. Al-MCM-41 itself was also modified with CuO through dry impregnation as the comparison. The influence of modification on the structure and performance of Al-containing MCM-41 was investigated by use of XRD and N_2 adsorption-desorption. A kind of volatile nitrosamine N-nitrosopyrrolidine (NPYR), the typical carcinogenic pollutant in environment, was used in both instantaneous adsorption and temperature programmed surface reaction (TPSR) to explore the adsorption and catalytic properties of these mesoporous composites. Besides, Mass spectrometer was employed to analyze the gaseous products of NPYR decomposed during TPSR procedure. The CuO modifier anchored in acid-leached sample possessed a higher activity in eliminating volatile nitrosamines, in comparison with those located on the parent Al-containing MCM-41.