Laboratory tests have shown that at least 80 percent of the dye pollutants are removed with the new method and material, and the researchers see good opportunities to further increase the degree of purification. Credit: Chalmers University of Technology, Sweden | David Ljungberg
Key points:
- Using a cellulose-based material, researchers have developed a method to easily remove toxins water.
- In laboratory tests, the method removed 80% of pollutants, including dyes from the textile industry.
- Real-world tests in India are ongoing .
Researchers at Chalmers University of Technology (Sweden) have developed a new method that can easily purify contaminated water using a cellulose-based material. This discovery could have implications for countries with poor water treatment technologies, as well as help combat the widespread problem of toxic dye discharge from the textile industry.
The key to the technology is cellulose nanocrystals, which have an excellent adsorption capacity.
“We have taken a unique holistic approach to these cellulose nanocrystals, examining their properties and potential applications,” said study author Gunnar Westman, associate professor of organic chemistry. “We have now created a biobased material, a form of cellulose powder with excellent purification properties that we can adapt and modify depending on the types of pollutants to be removed.”
The research was conducted in collaboration with the Malaviya National Institute of Technology Jaipur in India, where dye pollutants in textile industry wastewater are a widespread problem. The treatment requires neither pressure nor heat and uses sunlight to catalyze the process. Instead, as the contaminated water passes through the cellulose powder filter, the pollutants are absorbed and the sunlight entering the treatment system causes them to break down quickly and efficiently.
According to the study findings, in laboratory tests, the method removed 80 percent of dye pollutants—and the research team thinks they can increase that number.
But, conducting field studies in India is the next step. The Chalmers University of Technology research team is currently working with their Indian colleagues to get some of the country's small-scale industries to test the method in the real-world.
“Going from discharging completely untreated water to removing 80 percent of the pollutants is a huge improvement, and means significantly less destruction of nature and harm to humans,” said Westman. “In addition, by optimizing the pH and treatment time, we see an opportunity to further improve the process so that we can produce both irrigation and drinking water. It would be fantastic if we can help these industries to get a water treatment system that works, so that people in the surrounding area can use the water without risking their health.”
The scientists say the method can be applied to other water pollutants, as well. A previous study showed toxic hexavalent chromium could be successfully removed with a similar type of cellulose-based material. The group is also exploring how the research can contribute to the purification of antibiotic residues.