载体对Fe基催化剂CO_(2)催化加氢制低碳烯烃性能的影响  

Effects of supports on catalytic performances of Fe-based catalysts for CO_(2)hydrogenation to light olefins

作　　者：李广辉 张艳艳[1,2] 王萌[1,2] 高健[1,2] 张振洲 孙绍晖[1,2] LI Guanghui;ZHANG Yanyan;WANG Meng;GAO Jian;ZHANG Zhenzhou;SUN Shaohui(State Key Laboratory of Coking Coal Resources Green Exploitation,Zhengzhou University,Zhengzhou 450001,Henan,China;Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education,School of Chemical Engineering,Zhengzhou University,Zhengzhou 450001,Henan,China)

机构地区：[1]郑州大学炼焦煤资源绿色开发国家重点实验室,河南郑州450001 [2]郑州大学化工学院先进功能材料制造教育部工程研究中心,河南郑州450001

出　　处：《低碳化学与化工》2024年第12期19-26,共8页Low-Carbon Chemistry and Chemical Engineering

基　　金：国家自然科学基金青年项目(22208314);科技部“十三五”国家重点研发计划子课题(2018 YFB060450402)。

摘　　要：选择适宜载体对于合理设计高效CO_(2)催化加氢制低碳烯烃(乙烯、丙烯和丁烯)的新型Fe基催化剂十分重要。采用水热法合成不同载体并浸渍K和Fe制备了一系列Fe基催化剂(K-Fe/ZrO_(2)、K-Fe/ZnO、K-Fe/TiO_(2)和K-Fe/Al_(2)O_(3)),考察了载体对催化剂CO_(2)催化加氢性能的影响。采用XRD、N_(2)吸/脱附、Raman、CO-TPD、CO_(2)-TPD、原位Raman和水接触角测试等表征方法,研究了载体对Fe活性物种生成的诱导作用。结果表明,在温度320℃、压力2.0 MPa、原料气V(CO_(2)):V(H_(2)):V(Ar)=1:3:3和气时空速10000 mL/(g·h)的反应条件下,K-Fe/ZrO_(2)表现出较高低碳烯烃选择性(42.4%)和CO_(2)转化率(36.2%)。与其他催化剂相比,K-Fe/ZrO_(2)对CO和CO_(2)具有适宜强度的吸附性能,有利于CO_(2)活化和碳沉积,在获得更多Fe_(x)C_(y)活性物种的同时,抑制了烯烃二次加氢。此外,K-Fe/ZrO_(2)在反应过程中因碳沉积而具有较强疏水性,进一步减轻了Fe_(x)C_(y)被水氧化的程度,提高了低碳烯烃选择性。The selection of suitable support is crucial for the rational design of novel and efficient Fe-based catalysts for CO_(2)hydrogenation to light olefins(ethylene,propylene and butene).Supports were synthesized by hydrothermal method,and impregnated with K and Fe to prepare a series of Fe-based catalysts(K-Fe/ZrO_(2),K-Fe/ZnO,K-Fe/TiO_(2)and K-Fe/Al_(2)O_(3)).The effects of these supports on the catalytic performance of CO_(2)hydrogenation were investigated.The catalysts were characterized by XRD,N_(2)absorption/desorption,Raman,CO-TPD,CO_(2)-TPD,in suit Raman and water droplet contact angle tests,and the induction effects of supports on the generation of Fe active species were studied.The results show that under reaction conditions of temperature of 320℃,pressure of 2.0 MPa,feed gas V(CO_(2)):V(H_(2)):V(Ar)=1:3:3 and gas hourly space velocity of 10000 mL/(g·h),K-Fe/ZrO_(2)exhibites superior selectivity of light olefins(42.4%)and CO_(2)conversion rate(36.2%).Compared to other catalysts,K-Fe/ZrO_(2)has a suitable adsorption capacity for CO and CO_(2),which is beneficial for CO_(2)activation and carbon deposition.It also inhibits the secondary hydrogenation of olefins while obtaining more Fe_(x)C_(y)active species.Additionally,K-Fe/ZrO_(2)exhibites strong hydrophobicity due to carbon deposition during the reaction process,further reducing the degree of water oxidation of Fe_(x)C_(y)and improving the selectivity of light olefins.

关 键 词：CO_(2)加氢 低碳烯烃 载体 动态演变 Fe基催化剂 

分 类 号：TQ221.21[化学工程—有机化工] O643.32[理学—物理化学]