Fabrication of NiTi-MMO supported on in-situ generated TiO2 for dioctyl phthalate hydrogenation: A strategy for improving the utilization efficiency of Ni

Abstract

In this work, a NiTi-MMO/TiO2-R catalyst was prepared by in-situ generation of a TiO2 support during hydrothermal synthesis of the hydrotalcite precursor for NiTi-MMO. The formation of NiTi-MMO can reduce the size of metallic Ni particles, which can significantly improve the catalyst's activity, and the in-situ generated TiO2 support can enhance the dispersion of NiTi-MMO and the utilization efficiency of the active nickel species. The NiTi-MMO/TiO2-R catalyst showed high activity for the hydrogenation of dioctyl phthalate to dioctyl-1,2-cyclohexanedicarboxylate. The catalyst also exhibited good stability, maintaining the yield over 90 % after 6 cycles. Characterization results showed that a strong metal-support interaction was formed between the in-situ generated TiO2 support and the metallic Ni particles produced by the reduction of NiTi-MMO. The strong metal-support interactions formed between metallic Ni particles and the in-situ generated TiO2 played a crucial role in stabilizing the nickel species and preventing their aggregation, resulting in superior catalytic performance.