Preparation of Polyvinylchloride Nanofiltration Membrane: Investigation of the Effect of Thickness, Prior Evaporation Time and Addition of Polyethylenglchol as Additive on Membrane Performance and Properties

In this work, polyvinylchloride (PVC) membrane was prepared via casting solution technique andphase inversion method. N, N dimethylacetamide (DMAC) was used as primary solvent andtetrahydrofuran (THF) was used as a co-solvent. The effects of parameters such as membranethickness, evaporation time of casting film before immersion precipitation and addition ofpolyethylenglchol (PEG) on PVC membrane were studied in terms of deionized water flux (DIW),tensile strength, phase inversion time in non-solvent, water content, permeability flux, salt rejectionand antifouling properties.The results revealed that DIW decreased with increasing of membranethickness and prior evaporation time of casting film. The phase inversion time increased with increaseof membrane thickness and prior evaporation time. Tensile strength of fabricated membranes increasedsharply while evaporation time was increased. The results showed the reduction of water contentpercent with increase of casting film evaporation time. Addition of PEG from 1 to 4 % wt improvedflux sharply from 1.04 to 13.62 (L/m2.h). Rejection results showed reducing trend of salt rejection forfabricated membrane with different concentrations of PEG, except at the concentration of 3 % wt PEG.The results clearly showed more stable permeation flux during filtration process for blend PVC/PEGmembranes compared to PVC one.