New Mud-based Process Makes Water Desalination More Efficient

Desalination is one of the leading ways to bring water to places where it is scarce. Desalination is the process where salts and minerals are removed from sea water to make potable drinking water. While this process is far from new, it has always been a process that was not energy efficient.

Now, researchers from Australia and China have developed a new method to make the process more efficient. This could truly revolutionize the desalinization market, and more importantly, provide life-saving water to the people who need it.

A global issue
According to Open Gov Asia, water scarcity is a global issue that is only going to get worse. Currently 36 percent of the world faces water shortages for at least four months of the year. This figure is projected to rise sharply to 75 percent of the world by the year 2050.

Seawater desalination could offer a solution but it has always been costly and not energy efficient. Now, researchers have discovered a way to use solar power to evaporate seawater, which is a crucial step in the desalination process. This makes the energy-intensive procedure much more environmentally friendly.

And yet, there are drawbacks to the solar-powered method. Mostly, it is not very efficient because the salt ions in seawater impede the evaporation process. According to techxplore, studies had found that seawater evaporation rates were eight percent lower than purewater evaporation rates. 

Now, all that is about to change thanks to a new method pioneered by researchers from The University of South Australia and China.

It’s all about clay
In November of 2024, researchers from the University of Southern Australia, along with their fellow researchers from China, published their study in the journal Advanced Materials that pioneered a new method for solar-powered desalination. 

In this method, according to Open Gov Asia, they incorporate a clay like material into a photothermal hydrogel evaporator. This clay is composed of cheap, and readily available materials such as halloysite nanotubes, bentonite, zeolite, and montmorillonite. This helps create an ion exchange, making the evaporation process more efficient. Using this method, the researchers were able to reach an evaporation rate for seawater that was 18.8 percent higher than freshwater. 

“The minerals selectively enrich magnesium and calcium ions from seawater to the evaporation surfaces, which boosts the evaporation rate of seawater. This ion exchange process occurs spontaneously during solar evaporation, making it highly convenient and cost-effective,” Professor Haolan Xu, a professor of materials science, and one of the lead researchers on the paper, said in a press release from the University of South Australia. 

Sometimes a little bit of mud and clay can make a huge difference. And sometimes, all it takes is some creativity and thought to make the world better and precious drinking water available to all.