Peroxi-coagulation process: a comparison of the effect of oxygen level on color and TOC removals

Abstract

The present study investigates the feasibility of using peroxi-coagulation (PC) process for the oxidative degradation of real textile wastewater and the Taguchi experimental method was adapted to the system variables to find optimum levels of the operational PC conditions. The PC experiments were carried out in an electrochemical cell using a carbon fiber cathode. Additionally, an iron wire electrode as source of Fe2+ (catalyst) was used in an undivided electrochemical cell. This investigation demonstrates the treatment performance in case of using metallic iron sources in electro-Fenton (EF) reactions. For this purpose, several experiments were carried out to investigate the effect of medium dissolved oxygen level applying air and N-2 gases in electrochemical cell. Experimental data showed that oxygen level in the solution medium had a positive effect on PC treatment performance. According to the results, PC process with iron anode and carbon fiber cathode pairs gave the best results as 69.8% TOC and 100% turbidity results in oxygenated medium. The removal rates were decreased to 66.8% and 62.4% for TOC and turbidity, respectively when the solution medium becomes oxygen-free.