Study of reverse water gas shift reaction over Ni/Al2O3 and atomic-layer-epitaxy Cu catalysts

• Main Authors: Huai-Te Huang, 黃懷德
• Other Authors: Andrew Lin
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/36899160678450309183

碩士 === 長庚大學 === 化工與材料工程研究所 === 94 === The goal of this thesis is anticipated to develop some high performance catalysts for recycle of carbon dioxide and chemical conversion of CO2 to CO by means of catalytic reaction. This study contains: (1) the reverse water gas shift (RWGS) reaction on Ni/Al2O3 with and without；(2) the new Cu catalysts prepared by atomic layer epitaxy (ALE) technique applied in CO2 conversion to CO. One can see that CO and CH4 are the major products during RWGS reaction on Ni/Al2O3 and K-Ni/Al2O3 catalysts. The catalystic activity of Ni catalysts will slightly decrease with increasing amount of K additives, but the K promoter can effectively boost the reaction selectivity of CO. The CO2-TPD method is used to realize the adsorption sites of CO2 on Ni surface. It is found that K can promote to generate new adsorption sites on Ni, leading to increase activity if Ni catalysts. Interstingly, large amount of carbon deposition are found on Ni/Al2O3 contating K catalysts during reaction. The material of carbon deposition is analyzed by SEM, TEM and Raman spectrometer to find that there are some carbon fiber and disorder carbon structure formed on K-Ni catalysts surface. The formation carbon deposition is associated with K adding, tempersture (only for 500℃) and H2/CO2 ratio (H2 rich). The ALE Cu catalysts including: Cu/SiO2 and Cu/TiO2 are also applied to the RWGS reaction. Comparing to the typical impregnating Cu catalysts, these ALE Cu materials with low metal content and high dispersion can provide surprisightly highly catalytic activity.