Sustainable design of co-doped ordered mesoporous carbons as efficient and long-lived catalysts for H2S reutilization

Abstract

Selective catalytic oxidation of H2S into elemental sulfur has been recognized as the optimal route for H2S reutilization, but traditional metal catalysts show poor sulfur resistance. Herein, we report a solvent-free route for designing nitrogen and defects co-doped, ordered mesoporous carbons (ND-OMCs) from co-assembly of block copolymer template with nitrogen-containing oligomers and silica defects directing agent. Through thermal curing, carbonization and etching of silica, the microporosity tandem ordered mesopores, abundant nitrogen sites (6.13 wt%) and structural defects were introduced into ND-OMCs. The ND-OMCs were successfully applied as efficient and long-lived metal-free catalysts for H2S selective oxidation to sulfur, giving nearly 100 % H2S conversion and sulfur selectivity at only 150 °C. Their remarkable activities of ND-OMCs can be well-maintained over 157 h of continuous reaction, exhibiting the sulfur capacity as high as 3295 mg/g, which were much better than mostly desulfurizes such as commercial Fe2O3, g-C3N4, and nitrogen-containing, ordered mesoporous carbons.