Long-term-hydrophilic flat-sheet microfiltration membrane made from chlorinated poly (vinyl chloride)

Abstract

This article proposes a microfiltration membrane made from chlorinated poly (vinyl chloride) (CPVC) used in a bioreactor to purify wastewater. This material is suitable for such applications because it can form a highly porous structure with an appropriate distribution of suitable pore sizes. The objective was to apply hydrophilicity on the hydrophobic membrane using hydroxypropyl cellulose as the hydrophilization material. This substance can be transformed from solution to gel through heating, which could provide the potential for its long-term fixing on the membrane. The bioreactor membrane was prepared using CPVC, non-woven polyester, and hydroxypropyl cellulose and water was filtered from activated sludge at a flux rate of 1.0m/d (41.7LMH). The proposed membrane demonstrated stable operation at the applied flux rate for one month, while a conventionally prepared membrane, made from the same materials but without the hydroxypropyl cellulose, became unstable after two weeks because of increasing transmembrane pressure. The novelty of this article is found in the structure of the newly developed membrane in which small gel particles of hydroxypropyl cellulose are dispersed homogeneously and attached to the fine fibrils of the membrane providing high porosity with an open-pore structure.