摘要
合成兼具催化、吸附性能的复合催化剂是实现CO_2吸附强化CH_4/H_2O重整制氢过程的关键。研究采用共沉淀法制备了一系列具有类水滑石结构前驱体的Ni/Ca O-Al_2O_3复合催化剂,考察了制备过程中Ca/Al物质的量比对复合催化剂结构及性能的影响。结果表明,Ca/Al物质的量比可调控活性组分Ni与载体之间的相互作用力,进而调变复合催化剂的比表面积和活性组分Ni的分散度。当Ca/Al物质的量比为3时,Ni与载体之间相互作用力适宜,复合催化剂具有最大的比表面积(12.9 m^2/g)和最高的Ni分散度(1.07%);该复合催化剂在CO_2吸附强化CH_4/H_2O重整制氢过程中可得到95%的H_2浓度和88%的CH_4转化率,循环10次后,H2浓度仍能保持在93%以上。
CO2 enhanced sorption methane steam reforming for hydrogen production is a potential approach to economically provide hydrogen and to reduce CO2 emission. The key point for this process is to develop a composite catalyst with high catalytic and adsorptive capacity. Considering the tunable structure of hydrotalcitelike compounds,co-precipitation method was employed to synthesize Ni/CaO-Al2O3 composite catalysts by varying the molar ratio of Ca to Al. The results showthat the specific surface area and Ni dispersion of the assynthesized composite catalysts are greatly influenced by molar ratio of Ca to Al,which derives from the variable interaction between Ni and the support. When the molar ratio of Ca to Al is 3,the composite catalyst obtains a specific surface area of 12. 9 m2/g and Ni dispersion of 1. 07%. Catalytic evaluation shows that the composite catalyst possesses a H2 concentration of 95% and a CH4 conversion of 88%,and H2 concentration exceeds 93%even after 10 cyclic runs.
出处
《燃料化学学报》
EI
CAS
CSCD
北大核心
2017年第8期956-962,共7页
Journal of Fuel Chemistry and Technology
基金
国家自然科学基金(21406155
U1361202)
山西省高等学校创新人才支持计划(164010121-S)
山西省回国留学人员科研项目(2016-028)资助~~
关键词
制氢
复合催化剂
类水滑石结构
CO2吸附强化
hydrogen production
composite catalyst
hydrotalcite-like compounds
enhanced CO2 sorption
