Catalytic Methanation Of CO₂Over Ni Supported On Rare Earth Modified Carbon Nanotubes

With the rapid development of global industry, the emission of carbon dioxide, the world’s largest carbon source, caused by burning fossil resources increased year by year, and led to a lot of serious environmental and ecological problems. In recent years, in order to utilize CO2to things of value, scientists in many countries have put forward various scientific researchers on the solvement of carbon dioxide emission. Among them, the strategy of CO2cycling proposed by the Japanese scientists Hashimoto has attracted widespread attention of people. The step of carbon dioxide methanation in this strategy is thought to be the key of the whole cycle. So far, the researches of carbon dioxide methanation mainly focuse on the chose of active componets, catalyst carriers and additives.This paper studies the influence of different carriers of Ni-based catalysts on the carbon dioxide methanation reaction. A series of characterization measurements have been used in the study, including BET, IR, XRD, TPR and TEM. These results indicate that, the catalytic activity of using carbon nanotube as the carrier of Ni-based catalysts for carbon dioxide methanation has shown better reaction performance than traditional catalysts N1/Al2O3. It also indicated that the catalysts using the carrier of CNT modified by alkali KOH showed slightly better performance than the CNT modified by acid treatment.In addition, this paper also further investigates the effects of rare earth additives on carbon dioxide methanation. It is found that the addition of rare earth in catalysts obviously improves the catalytic activity. And based on this result, we further study the influences of different rare earth elements, different order of adding rare earth and different content of rare earth on the performance of the catalyst. After a series of catalyst characterizations, such as BET, XRD, TPR and XPS, it is found that the influences of different rare earth elements, content and addition order of rare earth on catalysts properties is mainly change the structure and electronic properties of catalystsThis study aims to seek the best catalysts of carbon dioxide methanation reaction, for the sake of cycling CO2in a great extent.