@Article{jrm.2020.011000,
AUTHOR = {Wendong Feng, Jian Li, Hongxiang An, Yunhai Wang},
TITLE = {Degradation of Spent Radioactive Ion Exchange Resins and Its Mechanisms by Fenton Process},
JOURNAL = {Journal of Renewable Materials},
VOLUME = {8},
YEAR = {2020},
NUMBER = {10},
PAGES = {1283--1293},
URL = {http://www.techscience.com/jrm/v8n10/40070},
ISSN = {2164-6341},
ABSTRACT = {Spent IERs are released during the operation and decommissioning of
nuclear facilities. The safe and efficient treatment of spent IERs is an emergent
problem in nuclear industry. IRN77 is a typical ion exchange resin widely used
in many nuclear power plants. Fenton process can degrade organic resins and
reduce the radioactive residues volume and the disposal cost significantly. In this
work, the IRN77 resin was selected as a model ion exchange resin and its treatment via Fenton process was investigated. The influencing factors for resin degradation, including catalyst dosage, reaction time, initial pH, temperature and
oxidant dosage were investigated and optimized via the single-factor experimental
method. Under the reaction temperature of 100°C and reaction time of 120 min at
initial pH of 2, more than 97% COD was removed with 1.66 g H<sub>2</sub>O<sub>2</sub> and 32 mg
FeSO<sub>4</sub>·7H<sub>2</sub>O added to per gram of wet resin. The catalyst dosage and H<sub>2</sub>O<sub>2</sub>
dosage can decrease 78% and 50% respectively compared to previous results.
SEM, FT-IR and ion chromatograph were employed to characterize the resin
beads, soluble organics and intermediates during the degradation reaction. Based
on the characterization results, the resin degradation pathway was discussed in
detail and it is proposed to three stages including beads dissociation, styrene
and divinylbenzene decomposition and carboxylic acids mineralization. During
the IERs degradation, formic acid, acetic acid, propionic acid and oxalic acid were
quantitatively monitored as main intermediates, and oxalic acid accounted for
over 90% of COD in the final residue solution. Fenton process is suggested as
a promising resin degradation method.},
DOI = {10.32604/jrm.2020.011000}
}