Pervaporation of hydrazine/water with ethylcellulose/4A zeolite mixed matrix membranes

Hydrazine, a hygroscopic liquid, needs to be dehydrated for its utilization as rocket propellant. The conventional processes of separation are cumbersome, as hydrazine forms an azeotrope with water apart from being explosive and highly alkaline. Pervaporation is a well-established safe, energy intensive process for separation of azeotrope mixtures. The selection of polymer for separation of hydrazine and water is of major concern as hydrazine is highly alkaline with pH of ∼13.6. Ethyl cellulose (EC) polymer withstands the high pH without any physical deformation or color change. Further, to increase the permselectivity, zeolite 4A nanoparticles were incorporated into the EC polymer matrix. The major focus of the present study was synthesis of zeolite 4A nanoparticles and preparation of ethyl cellulose- zeolite 4A mixed matrix membranes (MMMs). The zeolite particles and membranes were characterized using XRD and FTIR. The characteristics of the membranes were further observed by measuring contact angles. The pervaporation results were quite promising as the total permeate flux and selectivity were 18.35 g/m 2 h and 8.46 at 36 wt% of feed water concentration with the MMMs with highest zeolite loading. The performance of the MMM’s was comparatively better than pristine EC.