Pervaporative dehydration of industrial solvents using a zeolite NaA commercial membrane  A. Urtiaga, E.D. Gorri, C. Casado, I. Ortiz * Department of Chemical Engineering, ETSIIT, Universidad de Cantabria, Avda. de los Castros s/n, E-39005 Santander, Spain Received 5 January 2003; received in revised form 15 January 2003; accepted 16 January 2003 Abstract This work reports an experimental study on the pervaporative dehydration of two industrial solvents using a commercial zeolite NaA-type ceramic membrane (SMART Chemical Company Ltd., UK). The mixtures studied are tetrahydrofuran (THF) with an initial water content of 7.9 wt.% and acetone with an initial water content of 3.25 wt.%. Batch experiments were carried out until final water content was lower than 0.1 wt.% in THF mixtures and lower than 0.2 wt.% in acetone mixtures. The influence of feed composition and feed temperature on the pervaporation fluxes and selectivities has been investigated. In the THF dehydration for a water concentration in the retentate of 7 wt.%, the water flux increased from 0.43 to 0.98 kg m 2 h 1 for a temperature increase from 45 to 55 8C. In the acetone dehydration for a water concentration in the retentate of 3 wt.%, the water fluxes increased from 0.13 to 0.314 kg m 2 h 1 for a temperature increase from 40 to 48 8C. The separation factor for the THF /water separation was as high as 20 000, although the separation factor was found to be dependent on the feed water concentration. The water flux through the ceramic membrane shows a linear dependency with the driving force, which is the partial equilibrium vapor pressure of water in the retentate minus the partial pressure in the permeate, p w p p w : From the regression of the experimental data, preliminary values of water permeability were obtained that varied in the range 5.5 /10 3 kg/(m 2 / (h/mbar)) 5/K w 5/7.4 /10 3 kg/(m 2 /(h/mbar)) in the experimental range of operation temperatures. # 2003 Elsevier Science B.V. All rights reserved. Keywords: Zeolite membranes; Pervaporation; Tetrahydrofuran; Acetone; Dehydration 1. Introduction Pervaporation is a membrane separation tech- nology where a liquid feed mixture contacts the feed side of a selective membrane and the other side is typically under vacuum to provide vapor permeate [1]. Pervaporation has been widely studied as means of dehydrating solvents, whose recovery in the industry is frequently sought but difficult when an azeotrope is involved. In the case  Paper presented in the International Conference on Inorganic Membranes (ICIM 2002), June 23 /26, 2002, Dalian, China. * Corresponding author. Tel.:  /34-942-201585; fax:  /34- 942-201591. E-mail address: ortizi@unican.es (I. Ortiz). Separation and Purification Technology 32 (2003) 207 /213 www.elsevier.com/locate/seppur 1383-5866/03/$ - see front matter # 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S1383-5866(03)00037-6