CO_(2)加氢制甲醇中Cu/ZnO/Al_(2)O_(3)催化剂H_(2)S中毒机理研究  

Study on the poisoning mechanism of H_(2)S in Cu/ZnO/Al_(2)O_(3)catalysts for CO_(2)hydrogenation to methanol

作　　者：曾煜 田雨昆 陈子扬 陈铭 钟智勇 童婳 向茂 叶代启 陈礼敏 ZENG Yu;TIAN Yukun;CHEN Ziyang;CHEN Ming;ZHONG Zhiyong;TONG Hua;XIANG Mao;YE Daiqi;CHEN Limin(School of Environment and Energy,South China University of Technology,Guangzhou 510006;National Engineering Laboratory for VOCs Pollution Control Technology and Equipment,Guangzhou 510006;Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control(SCUT),Guangzhou 510006)

机构地区：[1]华南理工大学环境与能源学院,广州510006 [2]挥发性有机物污染治理技术与装备国家工程实验室,广州510006 [3]广东省大气环境与污染控制重点实验室,广州510006

出　　处：《环境科学学报》2025年第2期439-452,共14页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.22276060,21976059);广东省自然科学基金面上项目(No.2024A1515012636,2019A1515011849)。

摘　　要：本研究探讨了钢铁行业中典型杂质H_(2)S对商业甲醇合成Cu/ZnO/Al_(2)O_(3)催化剂在CO_(2)加氢制甲醇反应中催化性能的影响机制.表征结果表明,甲醇时空收率随毒化时间的延长出现先上升后逐渐下降的趋势;H_(2)S毒化预处理达1 h时,甲醇时空收率甚至高于新鲜催化剂,这主要是少量Cu^(0)NPs发生硫化通过促进甲酸盐中间体的生成从而促进甲醇的生成,同时反应过程中催化剂具有中毒可逆性;随着进一步毒化,生成的Cu_(2)S、CuS、ZnS等毒化产物逐渐破坏Cu^(0)NPs和ZnO的晶相结构,催化剂的硫化会导致反应过程中Cu颗粒的快速长大,且会影响ZnOx-Cu^(0)NPs-ZnO界面结构及其对碳物种的吸附,导致催化剂活性逐步下降;长时间毒化预处理后,Cu^(0)NPs和ZnO的严重硫化会导致催化剂基本失活.本研究揭示了H_(2)S对商业催化剂的毒化机理,为开发抗硫高效催化剂提供了理论基础,有助于实现钢铁行业的“双碳”目标.This study examines the effect mechanism of H_(2)S,one of the typical impurities in the steel industry,on the catalytic performance of commercial Cu/ZnO/Al_(2)O_(3)catalysts for CO_(2)hydrogenation to methanol.The characterization results indicate that the space-time yield(STY)of methanol initially increases and then decreases along with H_(2)S exposure.After 1 hour of H_(2)S pretreatment,the methanol STY exceeds that of the fresh catalyst,primarily due to the sulfurization of a small amount of Cu^(0)nanoparticles(NPs)which promotes the formation of formate intermediates and enhances methanol production.Meanwhile,the catalyst exhibits reversible poisoning behavior during the reaction.However,further H_(2)S exposure leads to the formation of Cu_(2)S,CuS,and ZnS,which gradually destroy the crystal structures of Cu^(0)NPs and ZnO.Additionally,the sulfurization of the catalyst causes rapid growth of Cu NPs during the reaction,and affects the interface structure of ZnOx-Cu^(0)NPs-ZnO and its ability to adsorb carbon species,thus leading to a gradual decline in catalytic activity.Prolonged H_(2)S exposure causes severe sulfurization of Cu^(0)NPs and ZnO,resulting in almost complete deactivation of the catalyst.This study elucidates the poisoning mechanism of H_(2)S on the commercial catalysts and provides theoretical foundations for developing sulfur-resistant catalysts,supporting the steel industry's"dual carbon"goals.

关 键 词：CO_(2)加氢 甲醇 H_(2)S 失活机制 Cu/ZnO/Al_(2)O_(3)催化剂 

分 类 号：X701[环境科学与工程—环境工程]