Carbon capture,utilization and storage(CCUS)technology has received increasing attention in order to cope with environmental problems such as global warming.CO2 hydrogenation to methanol is an important CCUS technology,realizing both CO2 resource utilization and chemical storage of renewable energy.In order to explore and optimize the process of CO2 hydrogenation to methanol,the catalytic per-formance of commercial Cu-ZnO/Al2O3 catalyst in the process of CO2 hydrogenation to methanol was tested in a fixed bed reactor.The catalytic effects of the catalyst at 448.15-543.15 K,1-3 MPa,and 3-9 molar ratio of H2 and CO2 were investigated.The results show that the CO2 conversion rate increases with the increase of reaction temperature.Methanol selectivity is mainly affected by tempera-ture and hydrogen/carbon molar ratio:the higher the temperature is,the lower the methanol selectivity is,and the higher the hydrogen/carbon molar ratio is,the higher the methanol selectivity is.Both CO2 conversion and methanol selectivity are enhanced by in-creasing pressure.Taking formate hydrogenation step as the rate control step of the reaction,the reaction kinetic model of the catalyst used in the process of CO2 hydrogenation to methanol was derived and established on the basis of LHHW kinetic theory.The model optimization function was constructed in MATLAB to solve the model parameters,and the reaction kinetic equation was obtained.The activation ener-gies of the two reactions are 42.4 and 122.1 kJ/mol,respectively.The recycling process of CO2 hydrogenation to methanol was established in Aspen Plus software,and the energy consumption of the recycling process was optimized by increasing the heat transfer between streams.The heat of the reactor outlet gas was recovered by a shell and tube heat exchanger for the preheating of the feedstock gas,which reduced the energy consumption of the preheating process by 86.2％.At the same time,the sensitivity analysis of flash separation tempera-ture and raw material gas preheating temperature was carried out,and the final choice of flash separation temperature was 323.15 K,raw material gas preheating temperature was 498.15 K.The process product is refined methanol with molar purity above 99.5％and metha-nol recovery＞99％.The optimal methanol production energy consumption is 4.84 GJ/t.
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