A U.S. patent for an innovative water filtration system design has been awarded to Tuskegee University researchers in the College of Engineering and the College of Veterinary Medicine.
The new filtration system uses silver nanoparticles immobilized on a porous carbon solid matrix and calcium carbonate silver nanoparticles to filter and recover water from various wastewater sources, including petroleum-containing water and water from industrial applications like car washes.
“Most of the water that is utilized in certain industrial applications must be collected and treated in order to remove contaminants that can include petroleum products, pesticides, herbicides, phosphates and detergents,” says Vijay Rangari, a professor of material science and engineering.
Rangari leads a Tuskegee team credited with the invention. Others on the team are Shaik Jeelani, Boniface Tiimob and Vitus Apalagya of the university’s Department of Material Science and Engineering, and Samuel Temesgen in the Department of Pathology.
The water filtration system is made with a low-environmental impact. The silver nanoparticles are prepared in a one-step wet ball milling process that does not use an environmentally hazardous reducing agent or an organic stabilizer. The calcium carbonate is preferably isolated from waste chicken eggshells.
Powdered-activated charcoal and silver nitrate are mixed together in ethanol and water to form the charcoal-silver nitrate solution that is then subjected to ball milling in the presence of polypropylene glycol to produce the silver nanoparticles on active charcoal.