[Evaluation of electrochemical treatment in degradation of wastewater contaminated by propylene glycol]

ABSTRACT

Propylene glycol is applied in many industries as raw material and can be released to the environment through wastewater of such industries. The biological treatment of solutions containing high concentration of propylene glycol is difficult and some problems can be observed during this process. The main objective of this study was the investigation of electrochemical degradation of propylene glycol and the parameters influencing on improving removal efficiency. In this study the degradation of propylene glycol was made by passing an electrical current though the synthetic wastewater containing propylene glycol. In order to investigate this process several types of electrode with applied voltage ranging between 5 to 50 V was used. Due to the effect of NaCl concentration on removal efficiency which was mentioned in the literature, the experiment was performed for different NaCl concentrations. In optimum condition, the maximum removal efficiency of propylene glycol [based on COD] was obtained equal to 90%. The results showed that rising applied voltage, NaCl concentration and retention time increase the removal efficiency. The optimum retention time was obtained equal to 50 min. The maximum removal was obtained when aluminum electrode was used. It can be attributed to the production of coagulant material such as Al[+3] during this process. The results revealed that this process can be useful for treating the industrial wastewater containing propylene glycol