The influence of the preparation method of the nickel-rhodium-aluminum based catalyst on its microstructure and catalytic activity for methane carbon dioxide reforming was studied. Aluminum sec-butoxide, Ni 1-metoxi 2-propoxide and rhodium nitrate were used as starting reactants. Three catalysts were prepared by the main methods: i) hydrolysis and thermal decomposition (TD), ii) hydrolysis and acid peptization (sol-gel, SG) and iii) hydrolysis, thermal decomposition and hydrothermal treatment (TD-HT). The three catalysts were evaluated for a period of 30 hours with the same metallic composition, 14% Ni, 1.4% Rh and the same operating conditions namely temperature, 790 ºC; W/FºCH4,in (relationship between mass of catalyst and the flow of methane in the feed stream), 0.5 g.h.mol-1 and CO2:CH4 ratio 1.0. The best bulk catalyst identified was (Ni-Rh-Al)TD-HT, showing excellent activity, selectivity, and stability. On the other hand the catalyst (Ni-Rh-Al)TD-HT was analyzed in a fixed bed reactor, modifying initial conditions such as temperature, W/FºCH4,in and CO2:CH4 ratio for a period of 120 hours achieving excellent catalytic activity, selectivity and stability. Studies on all catalysts evaluated reveal a low filamentous-type carbon deposition.
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