Comparative behaviour of hydrophilic membranes in the pervaporative dehydration of cyclohexane

Abstract

This work focuses on the performance analysis of several commercial membranes, provided by Celfa (VP-31, VP-43 and CF-23) and Sulzer (Pervap2201 and Pervap2201D) companies, as well as some tailor made sulfonated poly(ether ether ketone) (SPEEK) membranes, in the pervaporative dehydration of cyclohexane which is commonly employed as solvent in the synthetic rubber manufacture. Water permeate fluxes in the range of 13-250 mg/m2 min and satisfactory selectivity values were observed at very low water contents in the feed (below 90 mg/kg). A mathematical model based on the solution-diffusion theory is also presented, taking into account the mass transfer resistance offered by the fluid layer and the membrane itself, supported with experimental data obtained in a bench-scale radial flow pervaporation cell. Permeability values of the studied membranes resulted in the range of 3.2 × 10-11 to 2.3 × 10-9 m2/s.