High-efficiency steam reforming of methanol on the surface of a recyclable NiO/NaF catalyst for hydrogen production.

Low-cost methanol reforming to hydrogen has been the emphasis of development in the field of energy and environment all the time. Considering that the application bottleneck of the mainstream noble metal catalysts that are expensive and difficult to be recycled, a series of recyclable NiO/NaF catalysts were prepared for methanol steam reforming to hydrogen. And the selectivity, stability and recycling performance were comprehensively studied. Experimental results displayed that the NiO/NaF catalysts were able to efficiently steam reforming methanol to hydrogen. The 6%NiO/NaF catalyst possessed better hydrogen production performance, achieving 94% methanol conversion, 100% H 2 selectivity and 30 h stable operation under 450 °C. Moreover, the hydrogen production performance of the recycled 6%NiO/NaF catalyst was restored to the initial level of the fresh catalyst. Comprehensive characterization analysis confirmed that methanol steam reforming over NiO/NaF catalysts with dense structure was a surface fast reaction process. The Ni–O bonds were weakened by the strong interaction of NaF with NiO, making this catalyst had excellent low-temperature redox properties. Ni0 was the main active component, and the surface hydroxyl oxygen participated in and promoted methanol steam reforming. The formation and adsorption decomposition of methoxy group were the rate-determining steps in this reaction. [Display omitted] • NiO/NaF can efficiently steam reforming methanol to hydrogen. • Methanol steam reforming over NiO/NaF is a rapid surface reaction process. • Hydrogen production performance of recycled NiO/NaF reaches initial fresh level. • Surface hydroxyl oxygen participates in and promotes methanol steam reforming. • Methoxy formation and adsorption decomposition are the rate-determining steps. [ABSTRACT FROM AUTHOR]