摘要
利用可再生能源产生的绿氢将CO_(2)催化转化为甲醇,是实现碳中和的一条很有前途的路径。CO_(2)加氢制甲醇技术所用到的催化剂是一种ZnO-CeO_(2)双金属氧化物,考察了浸渍法、共沉淀法、沉淀包覆法和物理混合法等制备方法,并采用X射线晶体衍射(XRD)、N_(2)吸附-脱附、二氧化碳程序升温脱附(CO_(2)-TPD)、氢气程序升温脱附(H_(2)-TPD)、扫描电子显微镜(SEM)及X射线光电子能谱(XPS)等表征手段,对ZnO-CeO_(2)双金属氧化物催化剂的物化性质和催化CO_(2)加氢制备甲醇的性能影响进行了分析。结果表明,制备方法对催化剂物化性质和催化性能具有较大的影响。采用共沉淀法制得的ZnO-CeO_(2)催化剂表现出优异的催化性能,在温度为300℃、压力为4 MPa、质量空速为19 600 mL/(g·h)的反应条件下,CO_(2)转化率为4.61%,甲醇选择性达到80.64%,甲醇时空产率达到244.96 mg/(h·g);同时发现拥有丰富的氧空位缺陷浓度、较强H_(2)活化能力、较大比表面积及孔容是该催化剂催化性能提升的关键。
The catalytic conversion of CO_(2) to methanol using green hydrogen generated from renewable energy sources is a promising path toward carbon neutrality.The catalyst employed in the CO_(2) hydrogenation to methanol technology is a ZnOCeO_(2) bimetallic oxide.Various preparation methods such as impregnation,coprecipitation,precipitation coating,and physical mixing were investigated.Characterization techniques including X-ray diffraction(XRD),N_(2) adsorptiondesorption,carbon dioxide temperatureprogrammed desorption(CO_(2)-TPD),hydrogen temperatureprogrammed desorption(H_(2)-TPD),scanning electron microscopy(SEM),and X-ray photoelectron spectroscopy(XPS)were utilized to analyze the physicochemical properties of the ZnO-CeO_(2) bimetallic oxide catalyst and its impact on the catalytic performance in CO_(2) hydrogenation to methanol.The results indicated that the preparation method significantly influenced the physicochemical properties and catalytic performance of the catalyst.The ZnO-CeO_(2) catalyst prepared by coprecipitation exhibited excellent catalytic performance.Under reaction conditions of temperature of 300℃,pressure of 4 MPa,and weight hourly space velocity of 19600 mL/(g·h),the CO_(2) conversion rate reached 4.61%,methanol selectivity achieved 80.64%,and the methanol spacetime yield reached 244.96 mg/(h·g).It was observed that high concentration of oxygen vacancies,strong H_(2) activation capability,large specific surface area,and pore volume were crucial for enhancing the catalytic performance of this catalyst.
作者
占思进
刘仕轲
刘飞
姚梦琴
曹建新
ZHAN Sijin;LIU Shike;LIU Fei;YAO Mengqin;CAO Jianxin(College of Chemistry and Chemical Engineering,Guizhou University,Guiyang 550025,China;Guizhou Key Laboratory for Green Chemical and Clean Energy Technology,Guiyang 550025,China;Guizhou Engineering Research Center of Efficient Utilization for Industrial Waste,Guiyang 550025,China)
出处
《无机盐工业》
CAS
CSCD
北大核心
2024年第3期137-143,共7页
Inorganic Chemicals Industry
