Yb_2O_3助剂对Ni/SiC催化剂甲烷二氧化碳重整性能的影响

采用浸渍法制备了Ni/SiC和Ni-Ybx/SiC(x=2%、4%、6%、10%,质量分数)催化剂,在固定床反应装置中考察了催化剂在甲烷二氧化碳重整反应中的性能。利用BET、ICP-AES、XRD、H2-TPR、TG-DTA、XPS和TEM等技术对催化剂进行了表征。实验结果表明,Yb的适宜添加量为4%~6%。在800℃条件下Ni-Yb4/SiC和Ni-Yb6/SiC催化剂具有优异的催化活性和稳定性,在100 h的重整反应中,甲烷和二氧化碳的转化率始终保持在90%以上。Yb2O3助剂能够抑制镍颗粒的生长和减少碳沉积量,因此,Ni-Yb/SiC催化剂在连续反应中表现出稳定的活性。

Effects of Yb2O3 promotor on the performance of Ni/SiC catalysts in CO2 reforming of CH4

Ni/SiC and Ni-Ybx/SiC (x=2%, 4%, 6%,10%) catalysts were prepared by the impregnation method, and the performances of catalysts in the carbon dioxide reforming of methane were studied in a fixed-bed reactor.The catalysts were characterized by BET, ICP-AES, XRD, H₂-TPR, TG-DTA, XPS and TEM techniques.The experimental results indicate that the appropriate addition amount of Yb is 4% to 6%.Ni-Yb4/SiC and Ni-Yb6/SiC catalysts exhibit excellent catalytic activity and stability at 800 ℃, and the conversion of CH₄ and CO₂ can be maintained over 90% during the 100 h testing. Yb₂O₃ promotor can inhibit the growth of nickel nanoparticles and reduce the amount of carbon deposition,therefore Ni-Yb/SiC catalysts show stable activity in the continuous reforming reaction.