Abstract:

In industrial CO₂ hydrogenation to methanol，the introduction of H₂S gas will have negative impact on the activity and stability of catalyst used in the process.Based on this，InZrO _x and ZnZrO _x zirconium-based catalysts by microreaction synthesis method were successfully prepared Meanwhile，the influence law of H₂S gas on the structural properties and catalytic performance of zirconium-based catalysts in the CO₂ hydrogenation reaction was investigated.The results showed that under the conditions of T=573 K，P=3.0 MPa and GHSV=18 000 mL/（g_cat·h），when only CO₂/H₂ reaction gas was passed，the CO₂ conversion and CH₃OH selectivity of InZrO _x and ZnZrO _x catalysts were 7.2%，9.3% and 93%，92%，respectively.The CO₂ conversion and CH₃OH selectivity of both InZrO _x and ZnZrO _x catalysts were decreased to 0 when H₂S gas at a concentration of 5×10^-3 was introduced into the CO₂/H₂ feed gas.It was mainly due to the occupation of oxygen vacancies by H₂S gas，which led to the sulfur poisoning deactivation of the zirconium-based bimetallic oxide catalysts.When H₂S gas was stopped，the CO₂ conversion and CH₃OH selectivity of InZrO _x and ZnZrO _x catalysts were recovered to 5%，8.6% and 58%，84% respectively.The analysis showed that when the H₂S gas was stopped，the oxygen vacancy concentration was restored and the activity of zirconium-based bimetallic oxide catalysts was partially restored.This study clarified the principle of sulfur poisoning deactivation of zirconium-based catalysts and provided theoretical basis for the later development of sulfur-resistant catalysts.

Key words: microreaction synthesis, CO₂ hydrogenation to methanol, zirconium-based bimetallic oxides catalysts, sulfur poisoning, oxygen vacancy