EAPSI: Disinfection Properties of Visible Light Active Iron-containing Silicate Glass

Sarnosky Kamrie M, College Station TX

Investigators

Abstract

In order to address current issues in global water quality and sustainability, new environmentally friendly water disinfection technologies must be developed. Currently, chemicals commonly used to disinfect wastewater, such as chlorine, can react with other molecules in the water to create potentially harmful disinfection byproducts (DBPs). New technologies using ultraviolet (UV) light and semiconducting materials may be a byproduct-free alternative to chemical disinfection to inactivate pathogenic bacteria. However, solar light has less than 5% UV light radiation and artificial source of UV-light makes UV technology expensive. This project will test the disinfecting capabilities of visible light active iron-containing silicate glass. The research will be conducted in collaboration with Dr. Shiro Kubuki, of Tokyo Metropolitan University (TMU) in Tokyo, Japan, who has developed an iron-containing silicate glass that can be easily activated by visible light. This specific type of glass can be prepared from recycled glass bottles, and uses visible light, rather than UV-light, making it a cost-effective, byproduct-free alternative to chemical disinfection. Although it has been established that some semiconductors, such as titanium dioxide (TiO2), can effectively inactivate pathogenic bacteria, they require ultra-violet (UV) light to be effective. In this project, visible light active and iron-containing silicate glass will be used. Our hypothesis involves the use of iron-containing silicate glass made from recycled materials to eliminate pathogenic microorganisms without the harmful by-products produced by chlorine disinfectants and without the need for expensive and lengthy UV-light treatments. This study aims to: a) test the capability of iron-containing silicate glass to effectively inactivate pathogenic indicator organisms (Escherichia coli) by visible light-induced photocatalytic reaction and (b) explore the potential of using iron-containing silicate glass as an affordable "green" catalyst for water disinfection purposes. This award is under the East Asia and Pacific Summer Institutes program support for a U.S. graduate student and is jointly funded by NSF and the Japan Society for the Promotion of Science.