Metallic nickel-anchored biochar with non-metallic heteroatom modification: remarkably effective catalyst for steam reforming of methane

Abstract

In this paper, the effect of H₃PO₄-activated biochar on nickel-based catalysts for steam methane reforming (SMR) was explored. FTIR, BET, XRD, Raman, TEM, HRTEM, H₂-TPR and XPS analyses were used to characterize the supports and catalysts. The results showed that the activation of H₃PO₄ regulates the pore structure of the support and promotes the development of micropores into mesopores. Meanwhile, H₃PO₄ introduced more functional groups to promote the dispersion of Ni, which reduced the average particle size of the catalyst from 32 nm to 19 nm. In addition, it increased the number of defects of the catalyst and inhibited carbon deposition during the SMR process, which improved the activity and stability. The catalyst shows best performance at 650 °C, and the CH₄ conversion reaches 80.89%. After 80 h, the conversion decreased by only 2%.