Dimethyl Carbonate Are Researched From Carbon Dioxide And Methanol On Cu/ZnO-Al₂O₃ Catalyst Of Amorphous

Dimethyl carbonate(DMC) was usually used to methylation reagent and carbonyl reagent in place of toxic dimethyl sulfate, chloride and phosgene chemicals as a new green chemical products. In addition, DMC is a green organic solvents to coatings, medical and other fields. Because of its high oxygen content and octane number, it can be added to gasoline and diesel in order to reduce environmental pollution. Using CO2 and CH3 OH as raw material to direct synthesis of dimethyl carbonate(DMC) has a double meaning, not only can effectively reduce the content of CO2 in air, but also can get good DMC. In this paper, we carried out a systematic research to the direct synthesis of DMC from methanol and CO2.In this dissertation, we added La into the Cu/ZnO-Al2O3 catalyst for enhancing the catalytic activity. The structure of catalysts were characterized by XRD, TPD, BET and other means. Since then, we used zeolite to modified the catalyst. By characterization and testing, we found a kind of suitable zeolite additive.After that, we found the optimum reaction conditions for direct synthesis of DMC from methanol and CO2. The experimental results were as follows: when the content of La was 3%, the catalyst activity exhibited best. At this time, the conversion rate of methanol was up to 8.22%, the selectivity of DMC was 83.26%. After adding the HZSM-5 to the Cu-3%La/ZnO-Al2O3 catalyst, the activity of the catalyst was further improved. When the reaction temperature was 230 C, the reaction pressure was 1.0MPa, and the Catalyst consumption was1.0g, the conversion rate of methanol was up to 9.27%, and the selectivity of DMC was 84.76%.