Synthesis of Cu-Al Catalysts over Green SBA-15 from Corn Stack Ash for Catalytic Reduction of Nitric Oxide by Methane

Abstract

The aim of this research are to synthesize a mesoporous SBA-15 and to be used as a catalytic support for a Cu-Al/SBA-15 catalyst for reduction of nitric oxide using methane as reducing agent. The SBA-15 was synthesized via a sol–gel process by using corn stack ash (CSA) as a main silica source. Cu-Al bimetal was loaded on the support by incipient wetness impregnation method. The mesoporous SBA-15 and the synthesized Cu-Al/25CSBA were characterized by X-Ray Diffraction (XRD), Surface Area and Pore Size Analyzer, Transmission Spectroscopy (TEM) and NH₃- Temperature-Programmed Desorption (NH₃-TPD). The results reveal that SBA-15 can be prepared directly from 25% CSA without changing CSA to sodium silicate before synthesis. Effects of various parameters of catalytic activities on reduction of nitric oxide a continuous packed bed reactor - bimetallic Cu-Al content, reaction temperature and time were studied. The results showed that the catalyst with bimetal loading of 20%wt. (20% Cu-Al/25CSBA) exhibited the highest catalytic activities with the average NO conversion of 93 %, and its activity was quite stable over 2 h period of reaction. The introduction of aluminium (Al) generatesd the acidic sites and enhanced the reduction of NO compared to that of Cu/SBA-15 and 25CSBA, respectively.