Title: | Multipass membrane air-stripping (MAS) for removing volatile organic compounds (VOCs) from surfactant micellar solutions |
Author(s): | Cheng H; Hu Y; Luo J; Sabatini DA; |
Address: | "Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94025, USA. hefac@umich.edu" |
DOI: | 10.1016/j.jhazmat.2009.05.072 |
ISSN/ISBN: | 1873-3336 (Electronic) 0304-3894 (Linking) |
Abstract: | "Air-stripping is one of the most effective technologies for removing volatile organic compounds (VOCs) from surfactant solutions, although the presence of surfactant poses some unique challenges. This study evaluated the effect of a mixed surfactant system on the apparent Henry's law constant of tetrachloroethylene (PCE) and the efficiency of PCE removal from surfactant solutions using a lab-scale hollow fiber membrane contactor. Results show that the presence of surfactant significantly reduced the apparent Henry's law constant of PCE, and the reduction was proportional to the total surfactant concentration. PCE removal efficiency by membrane air-stripping (MAS) decreased as the surfactant system transitioned from solubilization to supersolubilization. Besides significantly reducing the apparent volatility of VOCs, the presence of surfactant brings additional mass transfer resistance in air-stripping, which makes it difficult to achieve high levels of contaminant removal, even at very high air/liquid (A/L) ratios. In contrast, multipass/multistage MAS operated at low A/L ratios could achieve near 100% contaminant removal because of less mass transfer limitation during each stripping pass/stage. Experimental results, together with model calculations demonstrate multipass (and multistage) air-stripping as a cost-effective alternative for removing VOCs from surfactant micellar solutions compared to the options of using large air strippers or operating at high A/L ratios" |
Keywords: | "Air Pollutants, Occupational/*analysis Algorithms Cost-Benefit Analysis Emulsions Membranes, Artificial Micelles Mineral Fibers Organic Chemicals/*isolation & purification Solutions Surface-Active Agents;" |
Notes: | "MedlineCheng, Hefa Hu, Yuanan Luo, Jian Sabatini, David A eng Netherlands 2009/06/13 J Hazard Mater. 2009 Oct 30; 170(2-3):1070-8. doi: 10.1016/j.jhazmat.2009.05.072. Epub 2009 May 22" |