Development of residue coal fly ash supported nickel catalyst for H2 production via glycerol steam reforming

Abstract

Coal fly ash (FA) supported Ni catalysts (Ni-FA) were synthesized via solid-state impregnation method and systematically characterized by XRD, N2-physisorption, H2-TPR/TPD, H2-pulse chemisorption, XPS, TPO, TGA, Raman, and TEM. The effect of different parameters including (i) types of FA, (ii) Ni loading (2.5–15 wt.%), and (iii) reforming temperature (530–730 °C), on the catalytic performance of yNi-FAx catalysts in glycerol steam reforming was investigated. The best performance in terms of activity (glycerol conversion to gas products = 98 %, H2 yield = 78.8 %) and stability (40 h, with low rate of coke formation and sintering 2.44 mgcoke·gcatalyst−1·h−1) was achieved for 7.5 % Ni-FA4 catalyst at 630 °C. This was attributed to a higher dispersion of Ni° active sites and stronger interaction with the support, due to the higher surface area of FA4 and the presence of nepheline (providing vacancy sites for anchoring Ni particles) and thermostable mullite.