title: Comparison of adsorbents for H2S and D4 removal for biogas conversion in a solid oxide fuel cell.
abstract: Biogas contains trace compounds detrimental for solid oxide fuel cell (SOFC) application, especially sulphur-containing compounds and volatile organic silicon compounds (VOSiCs). It is therefore necessary to remove these impurities from the biogas for fuelling an SOFC. In this paper, dynamic lab-scale adsorption tests were performed on synthetic polluted gas to evaluate the performance of a polishing treatment to remove hydrogen sulphide (H2S - sulphur compound) and octamethylcyclotetrasiloxane (D4 - VOSiC). Three kinds of adsorbents were tested: an activated carbon, a silica gel (SG) and a zeolite (Z). Z proved to be the best adsorbent for H2S removal, with an adsorbed quantity higher than [Formula: see text] at the SOFC tolerance limit. However, as concerns D4 removal, SG was the most efficient adsorbent, with an adsorbed quantity of about 184 mgD4/gSG at the SOFC tolerance limit. These results could not be explained by structural characteristics of the adsorbents, but they were partly explained by chemical interactions between the adsorbate and the adsorbent. In these experiments, internal diffusion was the controlling step, Knudsen diffusion being predominant to molecular diffusion. As Z was also a good adsorbent for D4 removal, competition phenomena were investigated with Z for the simultaneous removal of H2S and D4. It was shown that H2S retention was dramatically decreased in the presence of D4, probably due to D4 polymerization resulting in pore blocking.
authors.affiliation: a LGCIE-DEEP , Université de Lyon, INSA-Lyon , EA4126, 20 Avenue Albert Einstein, F-69621 Villeurbanne cedex , France.
authors.forename: Léa
authors.initials: L
authors.lastname: Sigot
authors.affiliation: a LGCIE-DEEP , Université de Lyon, INSA-Lyon , EA4126, 20 Avenue Albert Einstein, F-69621 Villeurbanne cedex , France.
authors.forename: Gaëlle
authors.initials: G
authors.lastname: Ducom
authors.affiliation: a LGCIE-DEEP , Université de Lyon, INSA-Lyon , EA4126, 20 Avenue Albert Einstein, F-69621 Villeurbanne cedex , France.
authors.forename: Belkacem
authors.initials: B
authors.lastname: Benadda
authors.affiliation: b CIRSEE , Suez-Environnement , 38 rue du Président Wilson, F-78230 Le Pecq , France.
authors.forename: Claire
authors.initials: C
authors.lastname: Labouré
mesh_terms: D000327:Adsorption; D056804:Biofuels / Q000032:analysis*; D002606:Charcoal / Q000737:chemistry*; D006862:Hydrogen Sulfide / Q000737:chemistry*; D058428:Silica Gel / Q000737:chemistry*; D012833:Siloxanes / Q000737:chemistry*; D018505:Waste Management / Q000379:methods*; D017641:Zeolites / Q000737:chemistry*
chemical_list: D056804:Biofuels; D012833:Siloxanes; D017641:Zeolites; D002606:Charcoal; D058428:Silica Gel; C024064:octamethylcyclotetrasiloxane; D006862:Hydrogen Sulfide
keywords: SOFC; adsorption; biogas purification; hydrogen sulphide; siloxanes