High-performance MgO-CaO/C for H2S oxidation prepared by a facile co-pyrolysis of magnesium gluconate and CaCO3

Abstract

A low-cost and facile approach to fabricate high-capacity desulfurizers has drawn much interest in the field of H2S removal. In this study, porous carbon materials with dual active components of MgO and CaO were synthesized by a facile co-pyrolysis of magnesium gluconate and CaCO3, and their performance on room temperature H2S oxidation was investigated. The H2S capacity of optimal CaO-MgO/C is 666.5 mg/gcat., more than 50 times that of MgO/C derived from pure magnesium gluconate. The characterization results indicate that compared to MgO/C, the CaO-MgO/C prepared by this co-pyrolysis strategy has a more developed pore structure and abundant basic sites. Consequently, the H2S adsorption and activation over as-prepared materials are promoted by the co-pyrolysis with CaCO3, and the storage space of oxidation products is also increased, resulting in an extraordinary enhancement in the H2S capacity. In addition, the desulfurization and deactivation mechanisms over the as-prepared CaO-MgO/C are illustrated. This work provides a novel and facile route of developing efficient materials for room temperature desulfurization.