Effect of Contact Time on Carbon Deposition and Catalytic Activity of Nickel Alumina Catalysts for Dry Reforming of Methane

Abstract Dry reforming of methane (DRM) reaction is advantageous in producing syngas with a low H 2 /CO, relevant to many industries. Effect of contact time on catalytic activity and carbon deposition is studied for DRM using Ni−Al catalysts, along with the effect of metal loading, reaction temperature, and reactant partial pressure (CO 2 /CH 4 ). Maximum CH 4 conversion (58 %) and CO 2 (59 %) were achieved at a higher contact time of 4.009 kg‐cat . h/kg CH4 . A maximum of 46 % CH 4 conversion was achieved at 1023 K with a contact time of 0.134 kg‐cat . h/kg CH4 . Higher CH 4 and CO 2 conversion were achieved with an excellent H 2 and CO yield due to the RWGS reaction with increased metal (Ni) loading (10–30 wt . %). When the reactant partial pressure (CO 2 ) changed from 0.1–0.3, the CH 4 conversion increased whereas CO 2 conversion decreased. FESEM images revealed the formation of whisker‐like carbon fibers for all loadings. For the best syngas output and stability in a Ni‐based catalyst, a combination of a basic support (alumina) at a higher contact time (~4.009 kg‐cat . h/kg CH4 ) and a CO 2 /CH 4 ratio of 1–1.5 at a moderate temperature of 873 K may provide best CO 2 adsorption with minimal coking.