Vapor Permeation of Aqueous 2-Propanol Mixtures through Carbon Hollow Fiber Membrane Prepared from Sulfonated Poly(Phenylene Oxide)

Abstract

The present study investigates the dehydration performance of a carbon hollow fiber membrane prepared from sulfonated poly(phenylene oxide) (SPPO) in the separation of aqueous 2-propanol (isopropanol, IPA) mixtures by vapor permeation. In pure water permeation, the flux increased with increasing feed pressure, which was larger than 15 kg m⁻² h⁻¹ at 150°C and 370 kPa. The effects of feed pressure, permeation temperature, and water concentration in the feed solution on the vapor permeation of water/IPA mixtures were studied. The SPPO carbon membrane showed water selectivity against IPA, mainly due to the molecular sieving mechanism in addition to the adsorption effect. The water permeance and ideal selectivity decreased with increasing total feed pressure from 165 to 365 kPa. Increasing the temperature resulted in lower water permeance, and the water permeance gradually increased with increasing water concentration at constant feed pressure. However, the SPPO carbon membrane showed excellent ideal selectivity, greater than 10,000, under various conditions. The carbon membrane also showed long-term stability and its performance was maintained for one month.