Electrokinetic reactivation of activated carbon: Possibilities for the treatment of the end-waste effluents

Abstract

Activated carbon is a common adsorbent material for the retention of organic and inorganic contaminants. The spent activated carbon is usually regenerated with a thermal process. The electrochemical regeneration of the activated carbon has been proposed as an efficient and sustainable alternative to the classical reactivation methods. The electrochemical treatment consumes less energy and produces less CO2 than the traditional thermal activation. The electrochemical regeneration uses a DC electric current directly applied to the carbon specimen. The electric current desorbs and mobilizes the contaminants retained in the activated carbon. At the end of the regeneration process, the contaminants released from the carbon remain in the electrode solutions (anolyte and catholyte). Such end-waste effluents require treatment before their final disposal. This work analyzed the chemical composition of the end-waste effluents and proposed and tested various technologies for the separation/degradation of organic and inorganic contaminants. Furthermore, the end-waste effluents may contain valuable materials: metals, phosphorus, specific organics, etc., that can be recovered using various selective separation processes.