AI‑guided design of 3D-printable gyroid spacers for scale‑resistant membrane distillation in sustainable water treatment.

Dual resistance Janus PDA/PVDF membrane for removal and concentration of short- and long-chain perfluoroalkyl substances via membrane distillation

Surface patterning in membrane distillation: Fabrication, mechanism, and performance enhancement

Pseudo two-dimensional heat and mass transfer study on randomly packed membrane evaporator

A survival analysis framework for predicting gypsum scaling risk in dynamically concentrating desalination systems.

To address the global water crisis, desalination technologies contribute about 1% of the global freshwater supply. Membrane-based desalination technologies offer high performance, operational ease, cost-effectiveness and high scalability compared to conventional thermal desalination modes. Among all membrane-based technologies, reverse osmosis is prevailing globally. However, the high energy demand of the reverse osmosis process and fouling in case of hypersaline feed streams motivate the exploration of alternative technologies, i.e., pervaporation. Pervaporation desalination involves dense hydrophilic polymer membranes to deal with high salt streams at low cost, along with less fouling than a few other membrane processes, i.e., reverse osmosis and membrane distillation. Mass transport through pervaporation desalination membranes is well-explained by solution-diffusion theory involving a tri-stage transfer, i.e., sorption, diffusion and evaporation. Since the last few decades, a green approach in all domains has offered chemical products and processes with the least hazards and minimal waste production. Application of biodegradable materials like poly(lactic acid) in combination with suitable green solvents, e.g., ethyl lactate, methyl lactate, cyrene, dimethyl isosorbide and gamma valerolactone for pervaporation desalination would be a good roadmap to meet the sustainability criterion. Some intrinsic features of poly(lactic acid) that make it a 'material of choice' for pervaporation desalination include hydrophilicity imparted by the presence of polar ester groups, high salt rejection, biodegradability with simple mineralization products, i.e., H2O and CO2, sustainable production, low toxicity, low carbon footprint, ease of processing and versatility. Poly(lactic acid) undergoes four interrelated degradation mechanisms: hydrolytic degradation, biodegradation, thermal degradation and photodegradation. The concern for poly(lactic acid) based pervaporation desalination is increased hydrolytic cleavage of poly(lactic acid) at high temperatures, which requires some modifications, e.g., nanoenhancement, additions of crosslinkers, surface modifications, addition of other polymers to prepare blends and post-treatments. These modifying strategies result in an increased stability and better performance of poly(lactic acid) films. However, optimization of various parameters relevant to such modifications leaves room for further research. This review offers a critical analysis of the need for biodegradable polymers with special focus on poly(lactic acid) rather than their fossil fuel-based alternatives, the environmental and health effects of all these polymers, cost estimation and possible performance-efficient, green and eco-friendly solutions.

Dual-layer membranes can offer significant advantages in desalination via membrane distillation (MD) compared to conventional single-layer designs. In this study, we report the development of a novel dual-layer nylon/polyvinylidene fluoride (PVDF) membrane with a Janus architecture, specifically engineered for application in sweeping gas membrane distillation (SGMD). The non-solvent induced phase separation (NIPS) method was used to cast PVDF solution on the top of a commercial nylon membrane. Water contact angle (WCA) measurements showed asymmetrical wettability. Scanning electron microscopy (SEM) confirmed that the PVDF layer was firmly anchored to the nylon support without signs of delamination. Desalination experiments were conducted using SGMD, where a significant flux enhancement as high as 81.2% was observed when the feed solution contacted the hydrophilic nylon surface while the hydrophobic PVDF surface faced the permeate side with gas flow. This enhancement was attributed to the high partitioning coefficient of the liquid-vapor mixture on the hydrophilic feed surface and the rapid vapor release across the hydrophobic permeate surface. Overall, these results demonstrate that hydrophilic membranes with small pore sizes (i.e., 0.22 µm) can serve effectively as supports when fabricated using the NIPS process, enabling new configurations for high-performance SGMD.

Separation membranes with inherent antiwettability and stability are highly desirable for membrane distillation (MD) in practical applications. In this study, hydrophilic-hydrophobic dual-layer membranes composed of a dense poly (vinyl alcohol)/halloysite nanotube (PVA-HNT) layer and a microporous polytetrafluoroethylene (PTFE) layer were fabricated to improve wetting and fouling resistance during the MD process. The incorporation of the HNT manipulated the crystallization and chain mobility of PVA, endowing the PVA-HNT layer with tunable water transport properties by adjusting the level of HNT loading. Benefiting from the hydrophilic top layer on PTFE, the dual-layer membrane with an optimal HNT loading of 5 wt% showed stable water vapor flux (7.6 kg/m2·h) while maintaining salt rejection above 99.95%. This performance was achieved using a 3.5 wt% NaCl feed solution with 0.4 mM sodium dodecyl sulfate at a feed temperature of 50 °C and permeate temperature of 10 °C. In contrast, the pristine PTFE membrane suffered from severe pore wetting, with its salt selectivity dropping from 99.5% to 91.5%. Antifouling performance was further evaluated using real landfill leachate in a 50 h treatment. The dual-layer membrane with a 5 wt% HNT maintained stable separation behavior with a 15.3% decrease in water flux, whereas the flux of the PTFE membrane declined by 70.5% in 30 h of operation. A distinct fouling layer was observed on the PTFE membrane surface after the operation, while no obvious fouling was identified on the dual-layer membrane, confirming its superior antifouling properties.

Shifts in environmental microbial community during membrane distillation for water production and wastewater treatment: a review

Membrane distillation is promoted as a thermally driven desalination process capable of utilizing low grade heat, yet its full thermal and hydraulic burdens have not been comprehensively resolved. The cooling burden is often neglected altogether, an assumption rarely met in real applications and especially in severe water stressed regions. This study develops a lumped thermodynamic framework that quantifies heating, cooling, and pumping duties across three representative membrane distillation configurations. Results show that cooling loads can reach the same order of magnitude as heating, up to 80–100% of the thermal input in open-loop feed setups, and remain of comparable magnitude even with internal or external heat recovery. Pumping penalties of 0.2–0.5 kWh/m 3 are unveiled starting from typical single-pass recoveries of only 2–6% and pressure losses of 300 mbar, underscoring the need for joint thermal–hydraulic optimization. The analysis also suggests a techno-economic trade-off: lowering specific energy consumption requires efficient heat utilization, typically achieved through effective system-level integration, large modules, minimization of terminal temperature differences, and internal or external heat recovery solutions; whereas compact designs entail modest capital expenditures but disproportionately high operational expenditures. Finally, a methodology for translating classical energy requirement indicators into actual energy consumption values is presented. The analysis compares different heating and cooling strategies, showing that feasibility relies not only on “free” heat availability, but also on effective heat sinks, optimized heat recovery, and low-resistance module hydraulics. • Cooling demand reaches 80–100% of heating in some membrane distillation configurations. • Cooling availability, not only heat supply, often constrains membrane distillation system feasibility. • Regardless of the configuration, single pass water recovery does not exceed ~10%. • Thermodynamic energy requirements differ from actual system consumptions. • In membrane distillation, “free” heat alone does not guarantee viability.

A smart superomniphobic membrane with switchable UV-cleaning and dark-healing for sustainable membrane distillation.

Fabrication of spherically-structured ceramic membrane for harsh high-salinity wastewater treatment via membrane distillation

Material losses in hard-gold plating during rinsing are a costly aspect of printed circuit board (PCB) production and lead to environmental impacts from raw materials that do not end up in the final products. Previously, washing water containing gold was not directly reused in the same process at AT & S Austria Technologie & Systemtechnik AG. The implementation of a membrane distillation (MD) system now allows for the direct recovery of discharged valuables from processing water as a concentrate, facilitating its reintegration into the process and significantly reducing input materials. A life cycle assessment (LCA) evaluated impacts on climate change, terrestrial eutrophication, and resource use and showed a reduction of approximately 25% in the investigated impact categories. Additionally, a water footprint profile demonstrated the potential for water quality regarding acidification and aquatic eutrophication, as well as regional water scarcity. While water scarcity is reduced by 23%, water quality indicators have a reduction of up to over 47%. Overall, the MD system demonstrated potential savings of 23% to over 47%, contributing significantly to sustainability in PCB production through a closed-loop approach.

Treatment of rare earth industrial wastewater by membrane distillation: Performance and membrane fouling characterizations

High-efficiency In2O3/Bi2O3 heterojunction photocatalyst for PFAS removal: experiments, mechanism and application in membrane distillation

A novel membrane distillation module integrating filter media within the feed channel for gypsum scaling regulation

High-efficiency solar-driven photothermal membrane distillation via permeate-side interfacial heating

Self-cleaning and anti-wetting MoO3@ZIF-8/PAES-CF3 nanofiber membrane enabling stable membrane distillation

Electrochemically assisted membrane distillation crystallization for efficient resource reclamation from ammonia-rich battery leachates

Performance and multi-objective optimization of hybrid solar–wind vacuum membrane distillation for sustainable desalination