Cu-Zn-Al-Fe/HZSM-5 Catalyst for Direct Synthesis of Dimethyl Ether

Cu-Zn-Al-Fe catalyst was prepared by the hydrothermal method,using HZSM-5 as a support.The influence of nitrate content,aging temperature and Fe content on the catalyst was investigated.SEM,BET,FT-IR and XRD were applied to the characterization of the catalyst.Dimethyl ether(DME) was synthesized by feeding CO2 and H2 into a reactor under the pressure of 4 MPa,the temperature of 260 ℃ and the H2/CO2 ratio(volume fraction) of 3.The results showed that when the mass fraction of nitrate is 10% and the aging temperature is 150 ℃,the particle size of the catalyst is the minimum(about 500 nm) and the specific surface area is 200.6 m2/g.During synthesizing DME,the catalyst with 5%Fe shows the best effect,with CO2 conversion ratio of 41.4% and DME selectivity of 45.2% obtained.