摘要
采用固相法、共沉淀法、柠檬酸法和溶胶-凝胶法制备了CuAl_(2)O_(4)尖晶石,在浆态床反应器上对其进行一氧化碳加氢反应活性评价,并对CuAl_(2)O_(4)尖晶石的结构进行了表征.研究发现,不同方法制备的CuAl_(2)O_(4)尖晶石在织构参数、表面富集程度和分解还原性能上存在明显差异,进而影响其催化性能.固相法所制尖晶石的孔径和孔容大,CuAl_(2)O_(4)表面富集程度最高,致使尖晶石分解不完全,但是其分解释放的CuO全部被还原,且Cu^(+)/Cu^(0)占比相当高,有利于提高产物中C2+OH选择性(达到31.1%).而表面富集程度相对低的其它3种尖晶石分解完全,但部分CuO未被还原,且还原产物中Cu^(0)占比提高,Cu^(0)和γ-Al_(2)O_(3)发生协同作用促进二甲醚的生成,其选择性最高可达72.9%.
The CuAl_(2)O_(4) spinels were prepared by the solid-phase method,co-precipitation method,citric acid method,and sol-gel method.The activity of CO hydrogenation over CuAl_(2)O_(4) spinel was evaluated in the slurry reactor.And the structure of CuAl_(2)O_(4) spinel was characterized by XRD,BET,SEM,TEM,NH3-TPD-MS,H2-TPR and XPS.The results showed that CuAl_(2)O_(4) spinel prepared by different methods had various texture parameters,surface enrichment degree,decomposition and reduction ability,which further affected the catalytic performance.The CuAl_(2)O_(4) spinel prepared by the solid-phase method showed a larger pore size and pore volume,and the highest CuAl_(2)O_(4) surface enrichment degree,resulting in incomplete decomposition of the spinel.However,CuO produce by the spinel decomposition was totally redyced,and the ratio of Cu^(+)/Cu^(0) was relatively high,which favored the formation of higher alcohols.The selectivity of C2+OH in the product was as high as 31.1%.The other three spinels with relatively low CuAl_(2)O_(4) surface enrichment were completely decomposed,but part of the CuO was not reduced.Moreover,the proportion of Cu^(0) was obviously increased.The synergistic effect of Cu^(0) and γ-Al_(2)O_(3) was beneficial to the production of dimethyl ether(DME).The highest DME selectivity was up to 72.9%.
作者
闫鹏泉
王竟荣
沈亚星
左志军
高志华
黄伟
YAN Pengquan;WANG Jingrong;SHEN Yaxing;ZUO Zhijun;GAO Zhihua;HUANG Wei(State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology,Taiyuan 030024,China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2021年第6期1846-1854,共9页
Chemical Journal of Chinese Universities
基金
山西省高等学校科技成果转化培育项目(批准号:2020CG012)
山西省自然科学基金(批准号:201601D011021)资助。
关键词
铝酸铜
一氧化碳加氢
二甲醚
低碳醇
浆态床
CuAl_(2)O_(4)
CO hydrogenation
Dimethyl ether
Lower alcohol
Slurry reactor
