Optimization of spent radioactive resins degradation by Fenton‐like oxidation using response surface methodology

Abstract

The degradation of spent radioactive resin by Fenton‐like process with Cu2+ as catalyst was optimized using response surface methodology (RSM) based on Box–Behnken design (BBD) method. The influence of three independent variables like catalyst concentration, H2O2 dosage, and initial pH value on resin degradation was investigated. The weight loss percentage of resin was evaluated using the quadratic model. Analysis of variance showed that correlation coefficient (R2) of the model was 0.9786, providing a satisfactory approximation of quadratic model with the experimental data. Out of three factors, especially pH value had significant influence on the weight loss percentage of resin. The weight loss percentage increased as pH decreased from 2.25 to 0.75. The conditions for resin degradation were optimized as follows: pH = 0.75, H2O2 = 20 mL, and catalyst concentration was 0.25 M. The confirmation experiment carried out at optimal conditions using RSM. The weight loss percentage was 95.80%. The predicted weight loss percentage was 96.19%, indicating that RSM based on BBD was a reliable method to optimize the operational conditions for resin degradation by Fenton‐like process. Finally, the intermediates of resin degradation were analyzed by ion chromatograph and GC‐MS. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1590–1596, 2016