Mass transfer analysis of the pervaporative separation of chloroform from aqueous solutions in hollow fiber devices

In this work the mass transfer analysis of the pervaporative separation of chloroform from aqueous solutions in hollow fiber devices has been performe d. Experimental results were obtained working at different initial chlorofo rm concentrations (200-1000 mg/l, different flow rate values (0.02-0.105 l/ min) and different temperature values (30-50 degrees C). A systematic methodology has been applied to the analysis of the mass trans fer rate of the separation process. Thus, starting with kinetic models base d on lumped parameters and widely applied in the literature for the descrip tion of similar systems, finally a mathematical model resulting from the so lution of the continuity equation of the feed phase flowing in laminar regi me through the hollow fiber module has been proposed. The diffusivity of ch loroform in the aqueous solutions was the only parameter required to descri be the separation rate values obtained at different flow rates and differen t temperatures. Average values of the diffusion coefficient were obtained at each temperatu re simulated and they were compared to the values predicted by the Wilke-Ch ang correlation observing similarity. The influence of the temperature was described through the equation D (m(2)/s) = 2.3 x 10(-4) exp(-3738.5/T). (C) 1999 Elsevier Science B.V. All rights reserved.