Effects of Cu and Fe Additives on Low-Temperature Catalytic Steam Reforming of Toluene Over Ni/AC Catalysts

Abstract

Steam reforming of toluene, a model tar compound, was carried out at low temperature of 600 °C using Cu–Ni and Fe–Ni bimetallic catalysts with different molar ratios supported on activated carbon (AC). For the Cu–Ni/AC catalysts, the carbon conversion of toluene rose and then decreased with the content of Cu increasing, and the best performance was achieved at the molar ratio of 0.2. However, the Fe–Ni/AC catalyst with the optimum composition of Fe/Ni = 0.1 had a better catalytic performance for toluene steam reforming than the Cu–Ni/AC catalyst (Cu/Ni = 0.2). During the duration test of 20 h, the Fe–Ni/AC (Fe/Ni = 0.1) catalyst showed higher activity for the average carbon conversion of toluene (93.8% vs. 92.9%) and better resistance. to carbon deposition than those of Ni/AC catalyst. Moreover, the metal average sizes of the spent Ni/AC and 0.1-Fe–Ni/AC were estimated to be 30.0 nm and 19.0 nm, respectively. Based on a variety of physiochemical characterization results, it is demonstrated that the addition of iron into Ni/AC catalyst led to good dispersion of Ni, and few coke formation and limited aggregation of nickel particles during reaction.