Sunlight-Driven Photolysis of Chlorine to Reactive Oxygen Species for Enhanced Inactivation of Chlorine-resistant Microbial Pathogens

EPA Grant Number: F13E10792
Title: Sunlight-Driven Photolysis of Chlorine to Reactive Oxygen Species for Enhanced Inactivation of Chlorine-resistant Microbial Pathogens
Investigators: Zhou, Peiran
Institution: University of Washington
EPA Project Officer: Lee, Sonja
Project Period: September 24, 2014 through September 24, 2016
Project Amount: $84,000
RFA: STAR Graduate Fellowships (2013) RFA Text |  Recipients Lists
Research Category: Academic Fellowships , Fellowship - Environmental Engineering

Objective:

This research will investigate the use of chlorine photolysis as a sustainable approach to enhancing the effectiveness of chlorine-based disinfection processes. It also will generate data sets of inactivation rate constants and CT values (disinfectant exposure) required for the inactivation of selected chlorine-resistant pathogens—i.e., Mycobacterium avium, Coxsackievirus B5 (CVB5) and C. parvum—during the sunlight-chlorine disinfection process and will enable modeling and optimization of the chlorine photolysis process, with the ultimate objective of facilitating practical implementation.

Approach:

The first stage of the research will use Bacillus subtilis spores as a model chlorine-resistant microorganism to validate and optimize the sunlightchlorine disinfection process by changing irradiation time, initial chlorine concentration, pH, etc. The second stage of the research will apply the optimized treatment condition to inactivate chlorine-resistant pathogens (M. avium, CVB5 and C. parvum) and generate data sets of inactivation rate constants and CT values of selected microorganisms.

Expected Results:

The key outcomes of the research will include (1) validation and optimization of the sunlight-chlorine disinfection approach to determine its effectiveness for inactivation of chlorine-resistant microbial pathogens in real water matrices and (2) generation of data sets of inactivation rate constants and CT values of M. avium, CVB5 and C. parvum inactivation by the proposed process under a wide variety of conditions (e.g., changes in solar irradiation, temperature and pH).

Potential to Further Environmental/Human Health Protection

The proposed water treatment approach could provide a simple, effective, inexpensive and sustainable water disinfection process to inactivate chlorine-resistant pathogens. More important, this can provide a revolutionary way to produce safe drinking water in point-of-use applications, such as backpacking, military operations and emergency water treatment following natural disasters.

Supplemental Keywords:

chlorine, disinfection, drinking water

Progress and Final Reports:

  • 2015
  • Final