关键词: 甲醇合成, ZnO/ZrO₂固溶体, 催化剂, 二氧化碳加氢

Abstract:

Direct hydrogenation of CO₂ to methanol provides a viable method for the fixation of CO_2，and also offers a strategy for storing hydrogen.In this study，a series of ZnO/MO _x （M=Zr，Ti） catalysts for CO₂ hydrogenation to methanol were synthesized by hydrothermal and co⁃precipitation methods，respectively.The activity evaluation indicated that 20%ZnO/ZrO₂-C catalyst prepared by co⁃precipitation method exhibited the most excellent activation with a CO₂ conversion of 9.0%，a methanol selectivity of 58.3%，while the methanol space time yield up to 0.321 g/（g·h） under the condition of 350 ℃，3.0 MPa and 24 000 mL/（g·h）.A series of structural characterizations were conducted，including X-ray powder diffraction，scanning electron microscopy，transmission electron microscopy，H₂ temperature⁃programmed reduction，N₂ adsorption⁃desorption，X-ray photoelectron spectroscopy and CO₂ temperature⁃programmed desorption.It was demonstrated that 20%ZnO/ZrO₂-C existed in the form of a solid solution state，which possessed relatively more uniform mesoporous structure，larger specific surface area，lower reduction temperature and high CO₂ activation capability.It indicated that the ZnO-ZrO₂ interface could be beneficial for methanol synthesis.The appropriate amount of ZnO was conducive to generating more ZnO-ZrO₂ interface，thereby enhancing catalytic performance.

Key words: methanol synthesis, ZnO/ZrO₂ solid solution, catalysts, CO₂ hydrogenation