Co3O4/Ce0.8Pr0.2O2催化剂用于乙醇水蒸气重整反应的研究

采用共沉淀法制备了Co3O4/Ce0.8Pr0.2O2催化剂,并将其用于乙醇水蒸气重整制氢反应,考察了Co3O4负载量以及Pr掺杂对催化剂性能的影响.采用X射线衍射、程序升温还原、热重分析和透射电子显微镜对催化剂的结构和表面性质进行表征.结果表明,催化剂中部分Co进入到载体的晶格中,使载体发生畸变产生更多的氧空位;载体中Pr掺杂有利于生成更多的氧空位,提高了催化剂的抗积碳性能,同时Pr掺杂可以增强Co3O4与载体之间的相互作用,提高金属Co的抗烧结性能;15%Co3O4/Ce0.8Pr0.2O2催化剂具有最好的催化活性,在反应温度为400℃,空速80 000 mL/(g.h),n(H2O)∶n(EtOH)=3的条件下可将乙醇完全转化;10 h稳定性测试结果表明该催化剂具有较好的稳定性.

Hydrogen Production from Steam Reforming of Ethanol over Co3O4/Ce0.8Pr0.2O2

Ce0.8Pr0.2O2 supported Co3O4 catalysts were prepared by co-precipitation method and used for steam reforming of ethanol to produce hydrogen.The influences of Co3O4 content and the doping of praseodymium on the catalytic performance were investigated.The catalysts were characterized by X-ray diffraction(XRD),temperature programmed reduction(TPR),thermal analysis techniques,and transmission electron microscope(TEM).The results show that some Co ions incorporate in the lattice of support,which results in a distortion of the support.This change would generate more oxygen vacancies.Besides,adding of Pr into ceria also favors the generation of oxygen vacancies in catalyst,which contributes to the improvement of anti-carbon deposition property.At the same time,adding Pr into ceria results in a stronger interaction between Co3O4 and support,which improves the anti-sintering stability of metal cobalt.15%(wt)Co3O4/Ce0.8Pr0.2O2 catalyst was very active and selective for hydrogen production via SRE,in which the conversion of ethanol could be obtained 100% at 400 ℃ with feed component of 20%(H2O+EtOH) and 80% N2 in volume ratio,GSGH=80 000 mL/(g·h),n(H2O)∶ n(EtOH)=3.