Reduction effect on the catalytic performances of NiAl-SPC takovite catalysts in syngas synthesis process

Abstract

Abstract In the downstream of the Oil & Gas industry and decline in oil production, the NiAl-HT derived hydrotalciteis a candidate as catalyst to produce syngas in the methane dry reforming process. Hydrotalcite are lamellar compounds of general formulation[M1-x 2+ Mx 3+ (OH) 2]x+[An-] x/n .m H2Owhere the ionic or cationic character can be tuned by the choice of the metal nature and oxidation degree. NiAl-SPC samples were obtained by coprecipitation at constant alkaline pH, then the product was thermal treated at 450°C for 6h to obtain mixed oxides phases. Samples prior and after calcination were characterized by XRD, ICP, BET, FTIR, SEM, TEM, TPR, TGA/DTA and Raman. Catalysts were examined in CO2 dry reforming of methane to examine the influence and the role of the reducibility ability on the catalytic reactivity and stability of NiAl-SPC hydrotalcite generics. They were reduced at 500°C, 600°C, and 700°Cfor 1h to evaluate the effect of its morphology changes on the carbon dioxide reforming of methane carried out at 700°C versus time on stream. It was shown that the reduction conditions strongly influence the reactivity of Ni metallic active phase catalyst, catalytic selectivity and its resistance to carbone deposit for methane reforming by carbon dioxide.This study proposes a further understanding of the synthesis, effects of additives and treatment of hydrotalcite as a catalyst for the DRM reaction. This knowledge will also be beneficial for the development of catalysts for other high temperature industrial applications (ammonia cracking, alcohol to hydrogen conversion...) and for longer term applications such as drug delivery or energy storage materials.