Publications Repository - Gdańsk University of Technology

Polyfluorinated alkyl substances (PFASs) may reach landfill leachates (LLs) due to improper waste management. In this study perfluorooctanoate (PFOA) and perfluorooctane sulphonate (PFOS) were used as representatives of PFASs in the decomposition on boron-doped diamond electrodes (BDDs) with high (10k ppm) and low (0.5k ppm) boron doping concentrations. The result shows that although better COD removal efficacies are obtained on the low-doped BDD (59 % after 8 h), the decomposition rate of PFOA and PFOS was not affected by boron doping. In LLs, at the current density of 75 mA/cm2, averaged removal efficiencies of 80 % and 78 % were achieved for PFOA and PFOS, respectively. But besides concentration of mother compounds, the presence of intermediates during electrolysis should be monitored. After 8 h of LL electrolysis, the presence of long-chain degradates C6 F13 and C6 F13 COO˗ was still observed only in 10k BDD-PFOA assays, while during 0.5k assays C 6F13 and C6 F13 COO˗ form more intesively at the beginning of the process. This indirectly confirms the more intensive generation of perfluoroalkoxy and hydroxyl radicals and higher susceptibility to electrolysis of PFOA’s long-chain intermediates on 0.5k BDD. This is the first study reporting BDD-electrolysis as promising in PFAS removal from the complex matrix of LLs, despite the oxidation of competing LLs components.

Authors

• dr Mattia Pierpaoli,
• dr inż. Małgorzata Szopińska link open in new tab ,
• Barbara Wilk link open in new tab ,
• dr hab. inż. Michał Sobaszek link open in new tab ,
• prof. dr hab. inż. Aneta Łuczkiewicz link open in new tab ,
• dr hab. inż. Robert Bogdanowicz link open in new tab ,
• dr hab. inż. Sylwia Fudala-Książek link open in new tab