Ni-based olivine-type catalysts and their application in hydrogen production via auto-thermal reforming of acetic acid

Olivine is abundant in the Earth’s upper mantle; it has applications in catalysts to enhance their stability in structures. The olivine-type catalysts were prepared by co-precipitation and hydrothermal synthesis and tested in the auto-thermal reforming (ATR) of acetic acid (AC), a model compound from bio-oil, for hydrogen production. In the meantime, the natural olivine impregnated with Ni was also tested. Characterisations of XRD, nitrogen physisorption, temperature-programmed reduction, and SEM-EDX were used to find the structure-reactivity relationship. The results indicate that the natural olivine produced a low H2 yield close to 0.17 mole of H2 per 1 mole of AC, while the olivine impregnated with Ni produced a H2 yield of from 2.19 mole to 2.73 mole of H2 per mole of AC. The olivine catalyst prepared by hydrothermal synthesis performed better in both activity and stability: the H2 yield achieved 3.06 mole of H2 per mole of AC and remained stable, which could be attributed to the higher surface area and stability with Ni inserted in the skeleton of olivine.