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The exploration of high-value-added materials using inorganic solid waste is a very important contribution to sustainable development. Coal gangue ash (CGA) as a solid waste was chosen as catalyst support. Five low-cost catalysts modified by different promoters (Co, Ce, Fe, Mn, and Mo) were prepared using a co-impregnation method. The toluene steam reforming tests were carried out at 800 °C under S/C = 2 (steam-to-carbon mole ratio). Catalyst characteristics were evaluated using X-ray diffraction (XRD), the Brunauer–Emmett–Teller (BET) method, temperature-programmed reduction (TPR), and Raman spectroscopy. The results showed that most promoters could interact with a Ni active compound and enhance the toluene conversion and H 2 yield. The Mo-Ni/CGA-1d (1d means the acid pretreatment time) catalyst performed the best catalytic activity, and corresponding toluene conversion and H 2 yield was equal to 92.6 and 62.3%, respectively, and it should be due to the formation of Mo-Ni alloy. Meanwhile, the Mo-Ni/CGA-1d catalyst exhibited higher stability during the runtime of 300 min compared with the Mn-Ni/CGA-1d catalyst, which can be attributed to the formation of the Mo 2 C structure with high-carbon-resistance ability. This is perhaps because the dissociation of CO 2 or H 2 O on the Mo 2 C structure surface is beneficial to the production of free oxygen species, which can accelerate the removal of carbon deposition on the catalyst surface.

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