Bimetallic LaNi_(1-x)Co_xO_3 (x=0, 0.3, 0.5, 0.7, and 1) Perovskite Catalysts for Tar Reforming to Syngas

摘要

Perovskite-type oxide with transition metal as active site presented a promising potential catalyst for tar elimination in gasification process. LaNi_(1-x)Co_xO_3 (x= 0, 0.3, 0.5, 0.7, and 1) were prepared by sol-gel method. The XRD profiles of the calcined catalysts revealed the mixed metal oxide forms including LaNiO_3 and LaCoO_3 rhombohedral structures. Good dispersion of La, Ni, and Co with homogenous structure was observed in synthesized catalyst. The particle size and surface area were in the range of 12.64-21.86 μm and 3.89-11.69 m~2 /g, respectively. Activity of prepared catalysts on tar elimination was carried out using steam reforming of toluene as tar model compound at 500, 600, 700, and 800°C. Product distributions obtained from reforming reaction with LaNi_(1-x)Co_xO_3 were between 40.24-88.84% of gas, 10.99-59.59% of liquid, and 0.15-0.17% of solid. Conversion to CO and H_2 were found to increase with the reaction temperature. The maximum carbon and hydrogen conversion to syngas, CO and H_2, of approximately 78.42% and 83.49% with acceptable heating value were occurred at 800°C using LaNiO_3 as catalyst. Crystal structure of used catalysts clearly showed destruction of perovskite structure and transformation to metallic Ni and Co at effective temperature.