Co²⁺/PMS based sulfate-radical treatment for effective mineralization of spent ion exchange resin (2022)

Muhammad Aamir Hafeez, Seok Ju Hong, Junsung Jeon, Juhyeok Lee, Bhupendra Kumar Singh, Neil C. Hyatt, Samuel A. Walling, Jong Heo, Wooyong Um

Chemosphere,Volume 287, Part 4,2022,132351,ISSN 0045-6535

DOI : https://doi.org/10.1016/j.chemosphere.2021.132351.

Abstract: Sulfate radical advance oxidation processes (SR-AOPs) have attracted a greater attention as a suitable alternative of the hydroxyl radical based advance oxidation process (HR-AOPs). In this study, for the first time we report liquid phase mineralization of nuclear grade cationic IRN-77 resin in Co2+/peroxymonosulfate (PMS) based SR-AOPs. After the dissolution of cationic IRN-77 resin, 30 volatile and 15 semi-volatile organic compounds were analyzed/detected using non-targeted GC-MS analysis. The optimal reaction parameters for the highest chemical oxygen demand (COD) removal (%) of IRN-77 resin were determined, and the initial pH, PMS dosage, and reaction temperature were found to be the most influential parameters for the resin degradation. We successfully achieved ∼90% COD removal (1000 mg/L; 1000 ppm) of dissolved spent resin for SR-AOPs by optimizing the reaction parameters as initial pH = 9, Co²⁺ = 4 mM (catalyst), PMS = 60 mM (as oxidant) at 60 °C temperature for 60 min reaction. The electron spin resonance spectroscopy (ESR) spectra confirmed the presence of SO₄^∙- and OH^∙ as main reactive species in the Co²⁺/PMS resin system. In addition, Fourier transform infrared spectroscopy (FT-IR) analyses were used for structural characterization of solid and liquid phase resin samples. We believe that this work will offer a robust approach for the effective treatment of spent resin generated from nuclear industry.

Keywords: Spent ion exchange resin; Cobalt; Peroxymonosulfate; Sulfate radical; Advance oxidation process; Mineralization