Adsorption and catalytic decomposition of dimethyl sulfide on H-BEA zeolite

• Published in: International journal of hydrogen energy 2020-10, Vol.45 (51), p.27644-27652
• Main Authors: Oshima, Kazumasa, Kadonaga, Rina, Shiba, Munehiro, Sohmiya, Minoru, Satokawa, Shigeo
• Format: Article
• Language: English
• Subjects: Desorption behavior; Desulfurization; Dimethyl sulfide; H-BEA zeolite; Solid acid catalyst
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2020.07.106

Catalytic direct decomposition of dimethyl sulfide (DMS) was performed using solid acid catalysts to develop an on-site hydrogen-free desulfurization system for utilization in small systems, such as fuel cells. DMS was decomposed to CH3SH and H2S at 500 °C on SiO2–Al2O3 and various zeolite catalysts. Among the catalysts, H-BEA zeolite with Si/Al = 18.5 (H-BEA-18.5) showed the highest performance for DMS decomposition at 500 °C. While the catalytic activity at 500 °C maintained a DMS conversion of greater than 30% for up to 114 h, a large amount of carbon deposition caused gradual deterioration. At a low temperature of 400 °C, DMS decomposition to CH3SH on H-BEA-18.5 continued for 100 h with a stable conversion of approximately 30%, although the adsorption of DMS on the catalyst surface was also confirmed. To achieve a high performance for the DMS decomposition, high temperatures were required to avoid the adsorption of sulfur species. [Display omitted] •Dimethyl sulfide was decomposed to CH3SH and H2S on solid acid catalysts.•H-BEA-18.5 showed the highest performance for DMS decomposition.•Adsorption of sulfur species on the acid site inhibited the reaction.•Carbon deposition caused deterioration in the reaction over long time spans.