Better wastewater treatment through oxidisation
Scientists have discovered a ‘co-catalyst’ that can improve the performance of water purifying chemicals.
Researchers at the University of California, Riverside have discovered a method to improve the way pollutants are removed from wastewater using Advanced Oxidation Processes (AOPs).
AOPs are a group of chemical treatment processes that use oxidation to remove organic materials from water. AOP are appealing solutions as the end products of the process are water and oxygen. The reactions are performed by hydroxyl radicals formed through the decomposition of hydrogen peroxide, a powerful oxidizing agent used in household and industrial settings.
Previously, the reaction between the ferrous salt, a catalyst for the process, and the water has left an iron-containing sludge that has to be treated as a secondary pollutant.
Yadong Yin, a professor of chemistry in UCR’s College of Natural and Agricultural Sciences, and colleagues have shown that adding into the mix another compound—called a co-catalyst—can dramatically improve the speed and efficiency of the reaction. The action of the co-catalyst reduces the amount of hydrogen peroxide and ferrous catalyst needed and helps prevent the formation of the sludge.
Yin says the co-catalyst, a powdered metal sulfide, is an inexpensive way to speed up the reaction by helping the ferrous catalyst’s performance and maintain its original form, instead of forming the sludgy by-product.
An expert on nanomaterials, Yin is now working to create smaller metal sulfide particles with more surface area to further increase co-catalyst performance.
“As the global demand for clean water continues to grow, it is critical that we develop cost-effective technologies to decontaminate polluted water,” Yin said in a statement. “This discovery provides the perfect catalytic system to improve an already promising process with applications in industry and municipal wastewater treatment.”
The discovery is outlined in the paper ‘Metal Sulfides as Excellent Co-catalysts for H2O2 Decomposition in Advanced Oxidation Processes’, published in the journal Chem 12 April.