Separation of VOC vapor from air by a surface-soaked liquid membrane module using triethylene glycol

A novel surface-soaked liquid membrane with triethylene glycol (TEG) and its flat membrane modules were used for the separation of VOC vapor from air. The liquid membrane setup with a vacuum pump had a 0.39 m2 membrane area and 21 μm liquid membrane thickness, which operated in a vacuum permeation mode with sweep air. The performance of the membrane process was tested for the separation of VOC vapors, such as benzene, toluene, etc., at a 1000 ppm concentration from air in a 1 m3 chamber. The TEG liquid membrane process showed a VOC removal rate comparable to a ventilation and adsorption process with active carbon. The TEG liquid membrane process proved to be useful for the VOC separation from room air. A model based on the permeability through the TEG liquid membrane predicted the separation performance of the liquid membrane process.