The high surface-area porous material, developed by researchers at the University of Illinois at Urbana-Champaign, can also remove the hazardous contaminants chloroform and trichloroethylene from water, both byproducts of the commonly used chlorine disinfection process.
"We've shown that we can remove all these impurities to well below the maximum contaminant levels established by the Environmental Protection Agency," said James Economy, a professor of materials science and engineering at Illinois.
"Having increased pore size and higher surface area, these fibres work much better than commercially available granulated activated carbon."
Atrazine is one of the most widely used herbicides. In the US alone, more than 75 million pounds of atrazine are applied annually.
"Because atrazine is toxic to humans, the Environmental Protection Agency has established a maximum concentration level of three parts per billion," Economy said. "By tailoring the pore size and pore surface chemistry of our fibres, we can achieve this limit."
To make their fibres, Economy and Illinois research scientist Zhongren Yue begin by coating fibreglass assemblies with a polymeric solution and a chemical activation agent. Then, under mild heat, the polymer cross-links, creating pores about 10-30 angstroms in size.
By controlling the chemistry, the scientists are able to tailor the fibres for specific target molecules, such as atrazine. The process therefore has potential applications for food and beverage production processes such as brewing.
"Our chemically activated porous fibres are nearly eight times more effective at removing atrazine to below EPA standards than commercially available activated carbon," Economy said. "In fact, our fibres can remove atrazine to well below one part per billion. And our fibres can be easily regenerated under modest conditions."
Yue discussed the fibres and presented the latest test results in a talk earlier this week at the 228th American Chemical Society national meeting in Philadelphia. The technology has been patented.
Filtration systems have become increasingly complex, and there is growing awareness of the important role that filtration plays in many aspects of food and beverage production. GEA for example recently developed a new pilot plant that gives food and drink manufacturers the opportunity to test filtration membranes before implementation.
The company claims that this allows processors to achieve optimum efficiency at a minimal cost.
"There are many different kinds of membranes," said Mads Skaarenborg, international filtration manager at GEA. "Spiral-wound membranes, ceramic membranes, even stainless steel membranes. All major food manufacturers will carry out some form of testing - if they do not own a testing plant, they will at least lease one to test new products."
The GEA Filtration Model M pilot plant is designed to test cross-flow membrane filtration applications in the microfiltration, ultrafiltration and nanofiltration ranges, and can be set up to evaluate a variety of membrane formats. According to the company, the modular design allows the plant to be built with customised solutions including construction materials and material finishes, operating configurations and parameters.