Improving surface characteristics and operational parameters of polyvinyl chloride ultrafiltration membranes: How to manipulate the performance of thin film composite forward osmosis membranes?

The environmental and economic costs are pivotal aspects that should be considered before the commercialization of any membrane separation-based process. Particularly, realizing this goal relies entirely on the key role played by fabrication and operational parameters. Herein, we introduced a systematic investigation for constructing thin-film composite (TFC) -forward osmosis (FO) membranes for direct fertigation applications. To the best of our knowledge, PVC membrane was rarely used as a porous top surface substrate for TFC-FO membranes. The PVC substrate porous structure and polyamide (PA) active layer were manipulated by variating their concentrations and reaction time to optimize the FO membrane performance. All necessary characterization tools were employed to visualize the fabricated TFC membrane's surface characteristics. The influence of feed solution concentration, membrane orientation, flow rate, and draw solutes on the FO work was also methodically tested. Results demonstrated that the porous structure-substrate membrane host polymer content had imparted a significant role in tailoring the TFC-FO performance concerning permeability and back-solute flux. The water flux was improved by 44.3 % with decreasing of the PVC amount, whereas water flux was improved by 48.13 % with decreasing of the M-phenylenediamine monomer (MPD) content from 3 to 1 wt% at constant tri-mesoylchloride monomer (TMC) content of 0.1 wt% in IP reaction conditions of a thin film. This was gone hand in hand with optimal operational conditions harnessed for optimizing the FO process.