(532bu) Probing the Role of Reserved Molten Salt during Methane Steam Reforming Under Low Steam to Carbon Conditions over Ni-Sn-Al Ternary Oxide Catalysts

Methane steam reforming (MSR) offers around 50% of the world’s hydrogen production, surpassing other common processes such as coal gasification and water electrolysis. Proceeding MSR reaction using feedstock with low H₂O/CH₄ ratio (<1.0) is beneficial to lower the energy input for steam generation and also to reduce the dilution effect on product gas, but adversely causes the issue of severe carbon deposition. Our group previously found that the Ni-Sn-Al ternary oxide synthesized via molten salt method possessed outstanding anti-coking ability during MSR under low H₂O/CH₄ conditions. Throughout the exposed works on molten salt synthesized catalysts, the molten salt medium is usually removed by multiple washing, which leaves its effect on catalytic performance unclear if it is reserved partially or completely. In this work, we prepared a series of Ni-Sn-Al ternary oxides with various molten salt contents by controlling the washing degree and further examined their catalytic performance. The synthesized samples showed different catalytic activities towards MSR and the contained molten salt presents a middle-of-the-road art, which small and high amount of them reduced the activity due to decreased Ni dispersion, while a middle amount of reserved molten salt can promote the reaction owing to improved electron distribution and appropriate basicity. Our research provides a different perspective on the conventionally abandoned medium when using molten salt method for catalyst synthesis.