Microwave-assisted dry reforming of methane

Abstract

The microwave-assisted dry reforming of methane over an activated carbon, which acted as catalyst and microwave receptor, was investigated. As a preliminary study, the CO 2 reforming of CH 4 was carried out using conventional heating and microwave heating in order to compare both heating devices. Higher conversions of CH 4 and CO 2 were achieved by microwave heating. Under microwave heating, various operating variables were studied in order to determine the best conditions for performing dry reforming with high conversions and the most suitable H 2/CO ratio. Thus, the dry reforming reaction was studied at different temperatures. An optimum range of working temperatures (between 700 °C and 800 °C) was established. In this range of temperatures, the dry reforming reaction is believed to take place as a combination of CH 4 decomposition and CO 2 gasification. Carbonaceous deposits from CH 4 decomposition are gasified by CO 2 and, as a result, active centres for the dry reforming reaction are constantly regenerated. The effect of the proportion of CO 2 fed in on the CH 4 and CO 2 conversions was also investigated. Small increases in the percentage of CO 2 fed in gave rise to large increases in both conversions, but especially in the case of CH 4. The volumetric hourly space velocity was also studied. It was found that the lower the space velocity, the higher the conversions obtained.