Pervaporation dehydration of ethylene glycol by NaA zeolite membranes

Home-made NaA zeolite membranes were used for pervaporation dehydration of ethylene glycol (EG)/water mixtures. Hydrothermal stability of the membranes in pervaporation was investigated for industrial application purpose. The membranes exhibited good stability for water content of less than 20wt.% at 100°C. The reduction of operating temperature was effective to improve membrane stability for operating at high feed water content (e.g. 30wt.%). The influence of feed water content and operating temperature on dehydration of EG was extensively investigated. A permeation flux of 4.03kgm ^-2h ^-1 with separation factor of >5000 was achieved at 120°C for the separation of the solution with 20wt.% water content. A pilot-scale pervaporation facility with membrane area of 3m ² was built up for dehydration of EG with the water content of 20wt.%, which showed technical feasibility for industrial application.