Removal of H2S and volatile organic sulfur compounds by silicone membrane extraction

✍ Scribed by I. Manconi; P. N. L. Lens

• Publisher: Wiley (John Wiley & Sons)
• Year: 2009
• Tongue: English
• Weight: 177 KB
• Volume: 84
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/jctb.2008

✦ Synopsis

Abstract

BACKGROUND: This study explores an alternative process for the abatement and/or desulfurization of H~2~S and volatile organic sulfur compounds (VOSC) containing waste streams, which employs a silicone‐based membrane to simultaneously remove H~2~S and VOSC. An extractive membrane reactor allows the selective withdrawal of VOSC and H~2~S simultaneously from the waste stream, while preventing direct contact between the waste stream and the absorbing solution and/or the biological treatment system. The influence of the sulfur compounds, membrane characteristics, extractant and pH was studied.

RESULTS: Sulfide and the VOCS studied, i.e. methanethiol (MT), ethanethiol (ET) and dimethylsulfide (DMS) were removed from the synthetic wastewater using a silicone rubber membrane. Methanethiol showed the highest (8.72 × 10^−6^ m s^−1^) overall mass transfer coefficient (k~ov~) and sulfide the lowest k~ov~ value (1.23 × 10^−6^ m s^−1^). Adsorption of the VOCS into the silicone membrane reduced the overall mass transfer coefficient. The k~ov~ when using Fe(III)EDTA^−^ as extractant (5.81 × 10^−7^ m s^−1^) for sulfide extraction was one order of magnitude lower than with anaerobic water (2.54 × 10^−6^ m s^−1^). On the other hand, the sulfide removal efficiency with Fe(III)EDTA^−^ was higher (84%) compared with anaerobic water (60%) as extractant. An additional mass transfer resistance was formed by elemental sulfur which remained attached to the membrane surface.

CONCLUSIONS: Extraction of sulfide and VOCS from a synthetic wastewater solution through a silicone rubber membrane is a feasible process as alternative to the techniques developed to treat VOSC emissions. Optimizing the aqueous absorption liquid can increase the efficiency of extraction based processes. Copyright © 2008 Society of Chemical Industry