Hydrogen sulfide removal from simulated synthesis gas using a hot gas cleaning system

• Published in: Journal of environmental chemical engineering 2023-04, Vol.11 (2), p.109592, Article 109592
• Main Authors: Thao Ngo, Thi Ngoc Lan, Chiang, Kung-Yuh
• Format: Article
• Language: English
• Subjects: Activated carbon; Calcined dolomite; Gasification; Hot gas cleaning system; Hydrogen sulfide; Zeolite
• ISSN: 2213-3437
• DOI: 10.1016/j.jece.2023.109592

This study investigated the removal, adsorption, and regeneration performances of simulated H2S produced from rice straw gasification in a hot gas cleaning system with combination of three types of adsorbents including zeolite, calcined dolomite and activated carbon. These experiments were conducted at 250 ℃ hot gas cleaning system and simulated synthesis gas containing hydrogen sulfide (H2S) concentration at 200 ppm. The experimental results indicated that the tested H2S removal efficiency and adsorbed capacity were observed to be adsorbed in decreasing order: activated carbon > calcined dolomite > zeolite. The adsorption capacities of zeolite, calcined dolomite, and activated carbon are 2.22, 3.16, 5.88 mg S/g adsorbents, respectively. In this research, the calcined dolomite shows poor adsorption-regeneration ability due to its deactivation by H2S. However, the tested zeolite and activated carbon could be fully regenerated at 350 °C with a stable sulfur adsorption capacity during four adsorption-regeneration cycles. These results gained from this study could significantly support researchers obtaining more information about the synthesis gas contaminants removal during hot gas temperature operation process. [Display omitted] •The H2S adsorption capacity order decreased as the activated carbon > calcined dolomite > zeolite.•H2S is adsorbed onto zeolite and activated carbon followed by adsorption-dissociation-oxidation steps.•Calcined dolomite was poisoned after four adsorption-regeneration test cycles by H2S.•Activated carbon and zeolite showed stable adsorption capacity during four adsorption- regeneration test cycles.