Clean water is becoming scarcer at a time when the world’s population is growing. Now, scientists at the University of New South Wales and the Royal Melbourne Institute of Technology in Australia have found a way to make dirty water clean enough to drink.
The researchers have developed a simple filtering sheet that cleans up dirty H2O.
The Aussies found that when they drop a piece of aluminum into the liquid form of the metal gallium, which occurs near room temperature, layers of solid aluminum oxide form along the gallium’s liquid surface. The aluminum oxide forms into thin sheets that can be “harvested” and used as water filters.
The sheets are very porous, but the pores are tiny enough to let clean water through while filtering out lead, oil and a variety of other toxins. The best news is that the process is simple: pour contaminated water into the neck of a bottle stuffed with one of these filtering sheets and wait for a minute or two while the water drips through. The filtered water is ready to drink.
More good news: while gallium isn’t a common metal, it’s not consumed in the reaction, so the same container of gallium can be used indefinitely to make many filters. Because the reaction uses virtually no energy, the filters can be produced for a few cents, compared to the usual water filtration systems that can run $100 or more.
The researchers aren’t seeking a patent and are releasing their discovery free of charge to the world, so that the 1 in 10 citizens of Planet Earth who lack access to clean water, including those in Flint, Michigan, can benefit as easily and inexpensively as possible.
Finding enough clean water to sustain the world’s increasing population remains one of the future’s great challenges. The Australian discovery can be a significant step toward overcoming that challenge.