Investigation of carrier gas transport through silica membrane for ethyl lactate separation and voc emission applications

Ethyl lactate has played a major role in daily living and chemical industry including fragrance, lubricant, additives and plasticizers. The esterification process of lactic acid and ethanol is an equilibrium limiting reaction. The selective removal of the products from the reaction mixture can be enhanced using a membrane. This work presents the carrier gas permeation behaviour with silica membrane for ethyl lactate separation and VOC applications. The experiment was carried out at the gauge pressure of 0.10 – 1.00 bar and 100 oC (373 K). Helium (He), argon (Ar), nitrogen (N2) and carbon dioxide (CO2) were used as the carrier gases. The membrane dip-coating process was carried out twice. The carrier gas flow rate was found to increase with increase in gauge pressure. The order of the gas molecular weight with respect to the gas permeance at 0.5 bar was He >Ar> N2> CO2. The gas permeance was found to decrease with respect to gauge pressure confirming the mass transfer limitations. The order of the gas permeance with respect to gauge pressure was He > N2>Ar> CO2.