Study On Preparation And Catalytic Activity Of Cobalt-based Catalysts For Carbon Dioxide Reforming Of Methane

The catalytic reforming of CH4 with CO2 has received extensive attention of industrial and academic circles all over the world. This reaction has also important environmental implications because both CH4 and CO2 are regarded as the main factors leading to the green-house effect. Thus, this process exhibits certain potential to be used as thermochemical heat-pipe for recovery, storage and transmission of solar and other renewable energy sources. At present, one of the key problems for the application of this process is the development of practical catalysts with high activity and high stability. But the catalyst for the reaction at home and abroad studies have been largely focused on precious metals and nickel-based catalysts, precious metal catalyst is expensive , carbon deposition of nickel-based catalysts at the same time is serious and has low stability. The work is focused on the study of Co-based catalysts, which has a series of excellent catalytic activity and unique resistance of Co catalysts by rational design.In this paper, it is mainly concerned that the effect of the different contents of cobalt-supported catalysts, calcinations temperature, reaction conditions and assistant on the catalysis is preperties of methane carbon dioxide reforming in a fixed-bed reactor. The catalysts were characterized by means of XRD, TPR, SEM, FESEM and TGA. The results showed that the reaction performance was optimum, under the condition of n(CO2):n(CH4) of 1:1 with a GHSV 12000 ml/ (h. g. cat) at 700℃, and 7% content of cobalt-supported catalyst, the methane conversion and CO selectivity were 87.68% and 75.37% respectively. The calcinations temperature of 700 oC and the calcinations time of 3h were the best preparation conditions to Co-based catalysts. Results showed that MgO promoter on Co-based catalyst had the best performance, which was methane conversion 94.87%, CO selectivity 85.21% and H2 yield 74.08% in the condition of n(CO2): n(CH4) of 1:1 with a GHSV 12000 mL/(h. g. cat) at 700 oC. Results from XRD and TPR experiments showed that the addition of MgO enhanced the activity of catalyst, and the catalyst had the best reducibility and dispersibility. The type of carbonaceous species Cγ, which may cause catalyst deactivation, was unfound to exist on the Co-MgO/BaTiO3 catalyst after reaction in 10h by using TG techniques.