Our research group has worked in the past on a variety of projects focused on leachate treatment from finding ways to improve the UV transmittance of landfill leachate to treatment and detection of emerging contaminants, such as pharmaceuticals, plasticizers, etc. We have used Fenton’s process and fungal bioreactors for treatment, and characterized dissolved organic matter in leachate. Our current work sponsored by Environmental Research and Education Foundation focuses on quantifying microplastics in leachate from municipal landfills and anaerobic reactors processing a variety of solids waste, e.g., food, agricultural and biosolids waste.
Quenching of hydrogen peroxide after UV/H2O2 advanced oxidation
Advanced oxidation is a highly effective process for treatment of organic contaminants and is frequently used for taste and odor mitigation and for treatment of water from sources impacted by human activity (indirect potable water reuse). However, it has some operational challenges on full-scale. One of the major challenges is dealing with residual hydrogen peroxide which interferes with subsequent chlorine disinfection by reacting with chlorine. Current methods of dealing with residual H2O2 involve adding more chlorine or using activated carbon to destroy H2O2. Both processes are expensive for a full scale water treatment plant, and our lab is evaluating alternatives to the currently established processes. This project is funded by the US Department of Interior Bureau of Reclamation.
Transformation products of antibiotics during chlorine disinfection
Wastewater contains trace amounts of antibiotics as well as other pharmaceuticals. During chlorine disinfection, pharmaceuticals react with chlorine and form transformation products, some of which may retain the properties of the parent molecule. We are testing the properties of the products that form with antibacterial activity assays and identify the product with high performance liquid chromatography coupled with mass spectrometry (HPLC/MS). Doxycycline forms products with antibacterial activity. The formation of the products is more prominent in clean water than in wastewater effluent matrix due to selective competitive reactions between chlorine and either organic matter or doxycycline. Testing of other antibiotics is planned in the near future.
