From salt water to fresh water. Experiment showing that nanostructures can improve water desalination process

More than 60% of the Earth’s people face severe water shortages. Desalination of seawater for some regions of the world is the main way to obtain fresh water. Reverse osmosis has become the most commonly used method for this. This process involves flowing seawater through a membrane. The high flow pressure is designed to eliminate minerals.

Innovations to ease the transition from saltwater to freshwater

Based on existing reverse osmosis processes, an international team of scientists has developed an innovative solution – the introduction of nanoscale structures. They published their discovery in Nano Research on November 18 this year.

To improve separation efficiency, the researchers carried out a process to create a multifunctional corona ether interlayer in a polyamide membrane. This gave it more nanoscale surfaces, leading to an increase in performance. In addition, the nanoscale pores are able to provide faster water transport channels. This is because the polyamide membrane exhibits much better permeability.

Will the new way of transitioning from saltwater to freshwater yield the expected results?

In their experiment, the researchers spread crown ether on a substrate impregnated with an aqueous amine solution, and then used a trimezoyl chloride/hexane solution. This was aimed at increasing the membrane’s efficiency by triggering polymerization reactions and leading to the formation of nanostructures. The corona ether layer reduces the reaction rate of interfacial polymerization and controls the reaction in a confined space, leading to the formation of an ultra-thin and uniform polyamide layer and thus increasing the separation efficiency. The next step in this research will be to see if these positive results are repeatable and scalable.