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CO 2 is one of the main greenhouse gases, but also the nature of the carbon-rich resources. Development and use of CO 2 is a modern industrial resources important research topics. Where CO 2 hydrogenation step synthesis of DME technology is the use CO 2 resources is an important way, the use of CO 2 Catalytic Hydrogenation DME can not only reduce CO 2 pollution of the atmosphere, but also be able to get important chemical products - dimethyl ether. For byproduct CO 2 and hydrogen plants is a significant economic effects. CO 2 hydrogenation of dimethyl ether is a complex chemical process, including CO 2 hydrogenation of methanol (MeOH) and methanol dehydration two steps. In this thesis, dimethyl ether synthesis from CO2 hydrogenation thermodynamics, kinetics, reaction mechanism and catalyst research were reviewed, and on this basis to do the following work: with hydrochloric acid modified montmorillonite, the load was coprecipitation The CuO-ZnO-Al 2 O 3 catalyst, to obtain CuO-ZnO-Al 2 O 3 / change of montmorillonite catalyst, using FT-IR, XRD means of its characterization, and in a fixed bed reactor differential activity evaluation was carried out, the system examines the acid concentration and reaction gas flow ratio, reaction temperature, pressure and other factors on the Catalyst performance. The results show that, CuO-ZnO-Al 2 O 3 / modified montmorillonite catalyst activity and stability, in 3MPa, 545K, hydrogen-carbon ratio of 3:00, CO 2 conversion rate of 26.5%, DME selectivity and yield were 16.7% and 4.4%, dimethyl ether and methanol, the total yield of 15.7%. With hydrochloric acid modified montmorillonite, the load evenly gel method of CuO-ZnO-Al 2 O 3 -Cr 2 O < sub> 3 catalyst, to obtain CuO-ZnO-Al 2 O 3 -Cr2O3 / modified montmorillonite catalyst, using XRD, TG / DSC and other means its characterization, and differentiation in a fixed bed reactor activity evaluation was carried out to determine the reaction temperature, pressure and other conditions on the catalytic hydrogenation of carbon dioxide dimethyl ether synthesis activity, the results showed that CuO-ZnO-Al < sub> 2 O 3 -Cr2O3 / modified montmorillonite catalyst at 545K, 3MPa lower carbon dioxide conversion rate of 28% and DME selectivity and yield reached 21.5 % and 6%.
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