Study of Short-Term Catalyst Deactivation Due to Carbon Deposition during Biogas Dry Reforming on Supported Ni Catalyst

摘要

Dry reforming experiments are performed for five different CH4/CO2 ratios at three different operating temperatures. The focus of the work is on the short-term catalyst deactivation due to carbon deposition and analysis of the nature and structure of deposited carbon at CH4/CO2 ratio of 2, which is typical for biogas. The dry reforming experiments indicate that the short-term deactivation is insignificant at an equimolar ratio of CH4 and CO2. The rate of carbon deposition becomes faster at higher CH4/CO2 ratios and higher temperatures. CH4 and CO2 conversions and the exit mole fraction of CO and H-2 confirm the occurrence of the reverse water gas shift reaction. Characterization of the spent catalyst and deposited carbon is performed using XRD, TGA, FTIR, and Raman spectroscopies, which indicates the presence of graphitic carbon and carbon nanostructures.