Optimized nickel-activated carbon catalysts for efficient SO2 reduction with methane: Performance and lifetime comparative analysis with alumina

• It aimed to design an active catalyst for SO 2 reduction with methane. • A facile wet impregnation technique was applied to introduce Nickel to the support. • SO 2 conversion rate exceeding 99% was achieved with the best catalyst. • A sulfur yield of more than 99% was obtained for the optimum catalyst. • The performance of activated carbon and alumina as catalyst bases was compared from an industrial perspective. • Alumina catalyst base demonstrated superior performance compared to activated carbon in this process. The catalytic removal of sulfur dioxide (SO₂) was evaluated using methane (CH 4 ) as a reductant, focusing on nickel catalysts supported on activated carbon. Various compositions of nickel oxide on activated carbon were impregnated and tested at temperatures between 550 and 800°C for the sulfur dioxide reduction reaction with methane. The catalyst containing 15% nickel showed the highest performance, achieving over 99% conversion of SO₂ and over 99.5% selectivity for the desired sulfur product. A comparative analysis was conducted between nickel oxide catalysts supported by activated carbon and alumina. The alumina-supported nickel catalyst demonstrated promising effectiveness in a lifetime test for industrial applications. The impact of activated carbon structure degradation on the performance of catalysts was also evaluated. It was found that as activated carbon structures degrade over time, the formation of new pores enhances carbon availability, thereby increasing the occurrence of undesirable side reactions. These results highlight how important catalyst support materials are in ensuring long-term stability and performance in sulfur dioxide reduction processes.