Abstract:
"Water treatment technologies are needed that can convert per- and polyfluoroalkyl
substances (PFAS) into inorganic products (e.g., CO2, F ) that are less toxic than parent PFAS compounds. Research on electrochemical treatment processes such as electrocoagulation and electro oxidation has demonstrated proof-of-concept PFAS removal and destruction. "
"However, research has primarily been conducted in laboratory matrices that are electrochemically favorable (e.g., high initial PFAS concentration [μg/L–mg/L], high conductivity, and absence of oxidant scavengers). Electrochemical treatment is also a
promising technology for treating PFAS in water treatment residuals from nondestructive technologies (e.g., ion exchange, nano-filtration, and reverse osmosis). "
"Future electrochemical PFAS treatment research should focus on environmentally relevant PFAS concentrations (i.e., ng/L), matrix conductivity, natural organic matter impacts, short-chain PFAS removal, transformation products analysis, and systems-level analysis for cost evaluation. "
"Ti4O7-electro oxidation and boron-doped diamond-electro oxidation perform similarly for PFAS mitigation with respect to removal and defluorination, making Ti4O7 electrodes a potentially cheaper alternative for PFAS treatment processes (Lin et al., 2018; Wang et al., 2020). In terms of energy, the EEO for PFOS removal using Ti4O7-electro oxidation was 3.6 kWh/m3 compared to 19.9 kWh/m3 for boron-doped diamond, demonstrating that PFAS removal using Ti4O7- electro oxidation was approximately 80% less energy intensive (Wang et al., 2020)."
Summary:
"Each tier represents a different foundation of research that needs to be examined in order to progress to the goal of engineering application
Tier one research focuses on proof-of-concept research to verify that a technology can work for a specific contaminant.
Tier two research focuses on assessing different applications of research and the influence of matrix factors, transformation products, and the costs associated with treatment.
Tier three focuses on research explicitly focused on implementation for drinking water treatment and includes studying the impact of environmentally relevant conditions and is validated based on regulatory targets.
Finally, the peak of the pyramid is “engineering application” which requires a stable foundation supported by the underlying tiers of research. "
Source: Ryan, D. R., Mayer, B.K., Baldus, C. K., McBeath, S. T., Wang, Y., &McNamara, P. J. (2021). Electrochemical technologies for per- and polyfluoroalkyl substances mitigation in drinking water and water treatment residuals. AWWA Water Science, e1249.
View full article here: https://doi.org/10.1002/aws2.1249
Magneli Materials has produced full scale applications that are being rolled out using this Ti407 technology. Contact us about our electrochemical systems using Ti4O7 today to learn more about our results.