Highly efficient H 2 and S production from copious waste H 2 S is beneficial from both environmental and energy. Whereas, the highly effective direct decomposition of H 2 S reaction faces a gigantic obstacle, that is, there is the severe thermal equilibrium limitation. Herein, a family of TiO 2 modified Mo x C as novel microwave catalysts have been developed. This work demonstrates that Mo 2 C, Mo 2 C-TiO 2 and MoC@TiO 2 microwave catalysts display excellent catalytic performance to recover both valuable H 2 and elemental S from the direct decomposition of H 2 S under microwave irradiation . The optimal H 2 S conversion of MoC@TiO 2 can be as high as 99.9% (almost complete conversion) at 700 °C, which greatly outpaces the corresponding H 2 S equilibrium conversion under microwave irradiation . This result of the chemical equilibrium limitation being broken shows an interesting phenomenon, namely a significant microwave selective catalytic effect by microwave catalysis in H 2 S decomposition reaction . In addition, the apparent activation energy of the Mo 2 C, Mo 2 C-TiO 2 and MoC@TiO 2 microwave catalysts reduced to 18.2 kJ/mol, 16.8 kJ/mol and 15.6 kJ/mol under microwave irradiation. The work supplies a strategy for highly effective valuable H 2 and S production from H 2 S decomposition reaction , and paves a path to high-value utilization of hazardous waste H 2 S resources with energy-saving heating method.
Qianqian Peng,Chengxuan Zhou,Shucan Qin,Jinbiao Liang,Shengyun Xu,Jiaming Mao,Jianming Shi,Yanrong Liu,Yunqian Ma
Electrochemistry allows for the simultaneous conversion of hydrogen sulfide (H2S) to hydrogen (H2) and sulfur, achieving atomic economy, and is a sustainable and cost-effective method. At the same time, an electrolyte with high conductivity and H2S absorption that can effectively capture H2S in an electrochemical process is essential. An ionic liquid electrolyte system for the absorption and electrolysis of H2S was constructed using the guanidine salt ionic liquid with amine-based functional groups as the carrier electrolyte, water as the solvent, and NaOH as the H2S absorber. The prepared electrolyte ([TMG][IM]-AE-30) showed a strong absorption of H2S with an equilibrium solubility of 100.82 g L−1. Under constant potential electrolysis at 1.0 V vs. RHE, the maximum hydrogen production rate reaches 2919.97 μmol h−1 and the Faraday efficiency reaches 99%, and the anodic product is α-sulfur with a production of 0.881 g after electrolysis for 8 h; the current density and hydrogen production rate are still higher than those of the AE systems after three cycles. Overall, the system has good hydrogen sulfide absorption and electrolysis performances, and [TMG][IM] can effectively improve the H2S absorption and electrolysis efficiencies.