Abstract:
The methane reforming with carbon dioxide, dry reforming, is an attractive route to produce the synthesis gas (H2-CO mixture) because of both environmental and commercial reasons. However, up to date it had no commercial application by itself because the lack of a catalyst capable at high temperatures and pressures required by industry. This research was aimed to study the effect of reduction temperature of Pd/Ce02/A1203 catalyst orl the dry reforming reaction since the reduction temperature has an influence on both nuclei and growth rates of Pd particles in the reduction step, which resulted in different Pd dispersion and catalyst activity. The activity of deactivated catalyst after regeneration was also investigated in order to study the potential of Pd-based catalyst to be commercially feasible in future. In this research, 1%Pd/ 8%Ce02/A1203 catalyst was prepared by deposition method and then used to perform the Temperature-Programmed Reduction. The catalyst was characterized using CO chemisorption technique in order to examine the dispersion of Pd at different reduction temperatures (200, 300, 400, and 500 OC) and after regeneration. The reforming reactions were conducted in a fixed bed reactor at 600 OC and atmospheric pressure, over the prepared catalyst in order to determine the activity of catalyst at different reduction temperatures (200, 300, 400, and 500 "C) and after regeneration. The methane conversion, H2/C0 product ratio, and production gas rate were also observed. According to the experimental results, the most suitable reduction temperature was 300 "C since it gave the best catalytic performance which are the highest methane conversion, the highest production gas rate, and the H2/C0 product ratio closest to 1. For the effect of regeneration, the deactivated catalyst after regeneration at 650 "C gave very poor catalytic performance (low methane conversion, production gas rate, and product ratio) compared to that of fresh catalyst. This can be caused by the sintering of Pd atoms at very high regeneration temperature (650 "C) resulting in very low Pd dispersion.