Reliable and efficient membrane processes for clean and sustainable production of fresh water from saline waste

Abstract

AbstractBACKGROUNDIncreasing water scarcity as a result of growing demand highlights the urgency for innovative solutions. Seawater desalination is emerging as a crucial answer, with direct contact membrane distillation (DCMD) emerging as a promising technology in this context. In particular, membranes produced from ionic liquids constitute a well‐established avenue for the preparation of membranes by nonsolvent phase inversion (NIPS) in the field of desalination.RESULTSTests carried out as part of the DCMD, using PVDF membranes modified with the ionic liquid (IL) MPF6 and TBAPF6 synthesized during this study, in particular those containing 50% TBAFP6, demonstrate a notable improvement in hydrophobicity (121.48°) and porosity(79%). The results suggest that the flux of the PVDF‐TBAPF6 membrane shows a clear improvement of 300% compared to the support alone. Various parameters such as salinity, temperature and flow rate were examined, highlighting their impact on membrane performance. The low energy parameters (Ea = 43.36 kJ mol−1, ΔH≠ = 40.86 kJ mol−1) indicate a diffusion mechanism of vapor molecules, occurring by successive jumps through the IL interaction sites.CONCLUSIONExtensive experimental investigations have carefully anticipated the permeate flow in DCMD, aiming to efficiently extract pure water. DCMD is positioned as a promising technology for desalination and treatment of BRINE solutions. Therefore, this study can make a significant contribution to the expansion of DCMD by facilitating the prediction and optimization of operational parameters, thereby paving the way for expanded application of this technology. © 2024 Society of Chemical Industry (SCI).