Clean water is a scarce commodity, and the situation is getting worse with many sources of fresh water drying up due to global warming. Under such dire circumstances, Dr Howard Stone from Princeton has come up with a novel idea to purify water without using any costly or complex filtration process.

Using a process called diffusiophoresis, he mixed carbon dioxide with water to form carbonic acid. This solution contains positively charged hydrogen ions and negatively charged carbonate ions, which mix with dirt and charge it. The charge difference makes it easier to isolate the dirt from clean water. The technology is similar to the one used to add fizz to soda.

Dr Stone’s process removes almost all the impurity in the water, leaving only 0.0005% of undesirable substances. Besides, the process uses far less energy than other purification methods, and doesn’t require any other material apart from carbon dioxide. Dr Stone proposes to acquire the required carbon dioxide from power stations and other industrial process. That would make the development of a full-scale version cost-effective as well.

According to the researchers, the process can be used to clean water from a pond or river that has bacteria and dirt particles