Synthesis of copper–nickel/SBA-15 from rice husk ash catalyst for dimethyl carbonate production from methanol and carbon dioxide

The SBA-15 was synthesized via sol–gel process by using rice hush ash and tetraethyl orthosilicate as silica sources at a ratio of 50:50. Subsequently, CuNi bimetals were loaded on the SBA-15 and were tested for the direct synthesis of dimethyl carbonate from CH3OH and CO2. FTIR showed that methanol reacted with pre-adsorbed carbon dioxide to form methoxy carbonate species that was the reaction intermediate. It was found that 0.5 g of catalyst with Cu and Ni bimetal loading of 5 wt% exhibited the highest activities. Moreover, the molybdenum modified catalyst showed greater beneficial effects on the stabilization of the catalyst.