Access to clean, freshwater is a growing challenge for many communities. Finding scalable desalination technologies to turn our world’s abundant saltwater into a drinkable resource would eliminate water shortages in many areas of the globe, but turning seawater into freshwater is no easy task.
Fortunately, a study has found success in desalination using a material called a metal-organic framework (MOF). The material can filter pollutants out of seawater and generate large amounts of freshwater using less energy than other common desalination methods.
MOFs are extremely porous and can spread out to cover large surface areas. They are perfect for trapping small molecules and particles to purify water. The team used a MOF called PSP-MIL-53 and used it to effectively trap salt and impurities in brackish water and seawater. Within 30 minutes, the MOF was able to reduce the total dissolved solids in the saltwater from 2,233 parts per million (ppm) to under 500 ppm which is well below the threshold of 600 ppm that the World Health Organization recommends for safe drinking water.
The MOF was able to produce as much as 139.5 L (36.9 gals) of freshwater per kg of material each day and can be quickly and easily cleaned for reuse by placing it in sunlight.
Other desalination techniques such as thermal desalination or reverse osmosis have drawbacks such as high energy consumption or heavy chemical use, but the researchers believe their MOF method is the most time, cost, and energy-efficient method to date. The ability to create drinking water from saltwater using simply a reusable material and the power of sunlight could be revolutionary for meeting the freshwater needs of the future.
