Advanced Water Management Centre

AWMC Seminar Program: Understanding formation of perfluoroalkyl acids and fate of emerging per- and polyfluoroalkyl substances in wastewater and sludge treatment processes

Yijing Li

Abstract: Per- and polyfluoroalkyl substances (PFASs) have been manufactured in high volumes and widely used for a variety of commercial and industrial applications since last century. The basic structure of PFASs consists of a carbon backbone with one or more hydrogen atoms replaced by fluorine atoms. Due to the extremely strong carbon-fluorine bond, PFASs are resistant to thermal, chemical and biological degradation. PFASs have attracted global interest and been extensively studies since perfluorooctane sulfonic acid (PFOS) was demonstrated to be ubiquitous in environment, human and biota. Many PFASs have been recognised as persistent, bioaccumulative and toxic which could impose adverse effects on living organisms. Wastewater treatment plants (WWTPs) are the major sources of PFASs into aquatic environment. PFAAs were found recalcitrant to be removed through conventional wastewater treatment processes, and even higher concentrations of PFAAs were observed in the effluent compared to influent, indicating the secondary formation of PFAAs from degradation of larger precursors compounds. However, there is no sufficient literature documenting the process of secondary formation of PFAAs during different wastewater treatment processes.

In the PhD study, the formation process of PFAAs will be investigated in activated sludge process and sludge digestion process. Contributions of precursor compounds to the secondary formation of PFAAs will be quantified by monitoring mass flows of legacy PFAAs in liquid and solids of samples combing with the indirect measurement of total PFAA precursors using total oxidizable precursor assay. Biodegradation of selected legacy and newly identified precursors will be assessed through spiking experiments.

AWMC hosts a free seminar series, every Friday at 9am in the AIBN Building.

Event Details
Date & Time: 
Friday, 25 January 2019
9am - 10am
Venue: AIBN Building 75, Level 1 Seminar Room

Event Contact: awmcseminars@awmc.uq.edu.au