低CO_(2)选择性的合成气制轻烯烃双功能催化剂  

Bifunctional catalyst for conversion of syngas to light olefins with low CO_(2)selectivity

作　　者：黄伟东 郑和平 郭玉静 毛璐瑶 袁浩 唐建华[1] HUANG Weidong;ZHENG Heping;GUO Yujing;MAO Luyao;YUAN Hao;TANG Jianhua(College of Chemical Engineering,Sichuan University,Chengdu 610065,Sichuan,China;Sichuan Coal Industry GroupLimited Liability Company,Chengdu 610091,Sichuan,China)

机构地区：[1]四川大学化工学院,四川成都610065 [2]四川煤炭产业集团有限责任公司,四川成都610091

出　　处：《精细化工》2022年第10期2092-2098,共7页Fine Chemicals

基　　金：国家自然科学基金(22178236,21878194)。

摘　　要：为开发高活性、高收率的合成气制轻烯烃(STO)双功能催化剂,以六水合硝酸锌、九水合硝酸铬和九水合硝酸铝为原料,通过共沉淀法制备非化学计量尖晶石Zn-Cr-Al氧化物{ZCA-x,其中x为锌用量,x=n(Zn)/[n(Cr)+n(Al)]},对其织构性质、晶体结构、形貌特征以及表面电荷性质进行了测试。结果表明,添加过量锌能够促进晶体粒径减小,表面氧空位增多。ZCA-1.25中锌含量较为适宜,将其与SAPO-34沸石分子筛结合为双功能催化剂用于STO性能研究,在进气组成n(H_(2))/n(CO)=2、空速3000 mL/(g_(cat)·h)、3.2 MPa、400℃反应条件下,实现46.9%的CO转化率,C_(2-4)^(-)烯烃收率高达15.9%,副产物CO_(2)选择性仅为29.2%。催化剂运行100h后活性良好。In order to develop bifunctional catalyst for conversion of syngas to light olefins(STO)with high catalytic activity and high yield,non-stoichiometric spinel Zn-Cr-Al oxide[ZCA-x,where x is the molar ratio of Zn/(Cr+Al),that is Zn content]was prepared by co-precipitation of zinc nitrate hexahydrate,chromium nitrate nonachydrate and aluminum nitrate nonahydrate,and the texture,crystal structure,morphology and surface charge properties were then measured.The results showed that excessive zinc addition could reduce crystal particle size and increase the surface oxygen vacancy.ZCA-1.25,with a suitable zinc content,was then composited with SAPO-34 zeolite,and its STO performance as a bifunction catalyst was then analyzed.Under the reaction conditions of inlet n(H_(2))/n(CO)=2,space velocity 3000 mL/(g_(cat)·h),3.2 MPa,400℃,CO conversion of 46.9%was achieved with the light olefins yield as high as 15.9%and the selectivity of CO_(2)by product only 29.2%.Meanwhile,the catalyst maintained good activity after running for 100 h.

关 键 词：CO_(2)转化 轻烯烃 双功能催化 低CO_(2)选择性 氧空位 催化技术 

分 类 号：O43[机械工程—光学工程]