Pervaporation Separation of Water-Alcohol Mixtures Using Hollow Fiber Composite Membranes
B. S. Cheon, J. W. Rhim*
Department of Chemical Engineering, Hannam University, Daejeon, Korea
The general separation processes for liquid and vapor mixtures need the energy consumed and causes of the cause of primary cost. From this point of view, the pervaporation separation process could be regarded as the energy saving process. The mass flux in pervaporation is brought about by maintaining the downstream partial pressure lower than the saturation pressure. In this process, the membrane acts as a thin solvent layer and the permeate concentration is mainly governed by the preferential solvation of the polymeric material.
In this presentation, it is introduced that the preferential alcohol(ethanol, iso-propyl alcohol, butanol) separation from the aqueous feed was carried out using the hollow fiber composite membranes according to the operating conditions, such as, the operating temperature, feed concentration, and membrane preparation composition, etc. The support membrane was poly(ether imide) hollow fiber ultrafiltration membranes and poly(dimethyl siloxane) was coated onto that hollow fiber membranes. First, the lab scale tests were carried out and then the pilot scale modules of the membrane area 1m2 were prepared and tested for alcohol mixtures inquestion. And also, the long-term period test has been done for several months for the pilot test. As a result, the stabilized and consistent results of both permeability and selectivity were obtained. All of these will be discussed in more detail at the meeting.
 Xianhong Liu, Yuan Sun, Xinhua Deng, "Studies on the pervaporation membrane of permeation water from methanol/water mixture", Journal of Membrane Science, Volume 325, Issue 1, 15 November 2008, Pages 192-198
 Ruihua Huang, Guohua Chen, Mingkun Sun, Congjie Gao, "Preparation and characterization of quaterinized chitosan/poly(acrylonitrile) composite nanofiltration membrane from anhydride mixture cross-linking", Separation and Purification Technology, Volume 58, Issue 3, 15 January 2008, Pages 393-399