Development of thin film nanocomposite membrane incorporated with plasma enhanced chemical vapor deposition-modified hydrous manganese oxide for nanofiltration process

Abstract

This study presents the development of novel thin film nanocomposite (TFN) membranes incorporated with poly(hexafluorobutyl acrylate)-modified hydrous manganese oxide (PHFBA-modified HMO) nanomaterials for nanofiltration application. The HMO surface is modified via single-step plasma enhanced chemical vapor deposition (PECVD) technique in order to improve its dispersion quality in organic solvent and minimize agglomeration in the resultant membranes. TFN membranes are prepared by dispersing HMO and PHFBA-modified HMO in the organic solvent that is used to prepare TFN1 and TFN2 membranes, respectively. The experimental results reveal that the TFN2 membrane (containing 0.05 w/v% PHFBA-modified HMO) exhibits the highest pure water permeability, which was 66.6% and 21.9% higher than the thin film composite (TFC) and TFN1 membranes, respectively. The remarkable enhancement in water permeability of the TFN2 membrane could be attributed to even distribution of modified HMO over the membrane surface. It is also found that the embedment of modified nanomaterials tends to enhance the polyamide cross-linking degree as well as membrane surface negativity, leading to promising rejection towards Na2SO4 (98.6%) and MgSO4 (97.6%). Furthermore, the TFN2 membrane is demonstrated to possess higher fouling resistance against inorganic and organic foulants. The filtration findings are consistent with the results obtained from instrumental analyses.