The effect Cooling Water Temperature in Air Gap Membrane Distillation for Breaking of Butyric acid – Water Azeotrope

Abstract

– Air gap membrane distillation is a thermal membrane separation method. In this method, the vapour phase is let through a hydrophobic membrane. The vapour pressure difference is created due to the temperature gradient across the hydrophobic microporous membrane, which is the driving force. I have investigated experimentally the feasibility of Air Gap Membrane Distillation module with PTFE hydrophobic membrane for the breaking of butyric acid-water azeotrope. Because of differences in diffusivity rates in the air, separation is possible. The influence of bulk feed temperature on the diffusivity of water and butyric acid, as well as the vapour pressure of butyric acid and water, was examined in this paper. Also, the effect of cooling water temperature (5-20 0 C) on total permeate flux, selectivity of butyric acid, and the concentration of butyric acid in permeate and retentate for various air gap (3-11mm) were experimentally studied. All other parameters were held constant during the experiment, including the Bulk Feed Temperature of 80 o C, Feed Flow Rate of 2 L/min, and Cooling Water Flow Rate of 2 L/min.