deSalSea

In the pursuit of global efforts to assure freshwater resources, especially for regions facing water scarcity, seawater desalination stands out as a promising solution to expand global freshwater reserves. Even though, forward osmosis (FO) offers solutions to multiple challenges of other desalination technologies, still it faces limitations hindering its widespread practical application. To address these challenges, an essential aspect is the development of a draw solution (DS) for the FO cell, capable of generating high osmotic pressures and exhibiting precise thermally-induced transitions across a desired temperature range to facilitate low-energy regeneration, minimizing reverse solute flux and viscosity, enhancing water flux and reducing internal concentration polarization. The semipermeable membrane is another component of FO that have to overcome the current drawbacks of limited selectivity and sensitivity, fouling, mechanical resistance and up scaling limitations. The deSalSea project is aligned along the entire value chain of FO technology. The interdisciplinary Spanish-French-Czech consortium present complementary expertise within the individual FO processes and novel ideas to improve the sustainability and to detach the production dependence on petroleum-based products, while simultaneously increase the performance and decreased costs of FO. To achieve it, the first project aim is to design completely novel polyzwitterionic chains for DS based on sustainable resources, capable of responding to multiple stimuli (such as thermal and pH changes). These chains, rich in charges along their polymer backbone, ensure high osmolarity at lower molar concentrations, thereby reducing viscosity, reverse flux, polymerization concentration, and regeneration costs., environmentally friendly end-of-life solutions for DS will be ensured. The design of novel DS components is based on systematic theoretical and experimental studies to deeply understand the peculiar responsive polyzwitterion behaviour and create a base for molecular design of such chains that will have controlled responsive behaviour to ensure negligible costs for DS regeneration, as second deSalSea aim. Such DS solution have low TRL1 and during the project life we expect to rise it to TRL3. Within the next project aim, biomimetic Aquaporins AQPs membranes will be implemented in FO cell, based on Artificial Water Channels (AWCs), constructed from artificial molecules defining a water-pore superstructure, surrounded by a hydrophobic exterior toward the membrane environment. It is expected increasing desalination efficiency by using natural principles by 3 folds of the currently best reverse osmosis membranes, while achieving 99.5-99,9% salt rejection. The AWC-based membranes have high TRL of 4-5, and is expected to be raised after project realization to TRL6. Fourth aim of deSalSea is to integrated all the individual processes within novel FO technology and develop a demonstrator device on laboratory scale, giving rise to TRL4 of the complete FO process. Finally, the project will evaluate its outcomes in terms of energy efficiency, economic viability, and environmental impact, aligning with the Sustainable Development Goal 6 (SDG6) of "Clean Water and Sanitation." Through comprehensive life cycle assessments (LCAs) and material circularity strategies, the project aims to minimize waste and carbon emissions while ensuring access to clean water. The impacts of deSalSea are related with the increased substitution of fossil-based materials with biobased alternatives, ultimately leading to zero waste after their useful life. Successful development of novel water-borne materials that offer end-of-life solutions will be the primary indication of economic benefit. The DS regeneration and recycling in the process will enhance material circularity, enhanced sustainability and reduced environmental impact and minimized carbonization while providing clean water access to population.