Preparation of NiGa2O4 nanoflower for boosting catalytic hydrolysis of carbonyl sulfide

Abstract

A nanoflower-like NiGa2O4 spinel was designed for the catalytic hydrolysis of COS. The COS hydrolysis activity of the NiGa2O4 nanoflower was significantly improved as compared to the Fe5Ga3O12 and CoGa2O4, which was ascribed to the enhanced diffusion and surface alkalinity. In the reaction, COS adsorption was significantly strengthened on the basic sites, and thereby the formation of intermediates such as HCO3– and HSCO2- was facilitated. The NiGa2O4 catalyst also demonstrated excellent sulfur tolerance and stability in long-term testing for COS hydrolysis using simulated industrial gas at 100 °C, maintaining ∼100% of H2S selectivity in the first 70 h.