Electrochemically synthesized GIC-based adsorbents for water treatment through adsorption and electrochemical regeneration

The flake GIC material delivered a small adsorptive capacity for a number of organic pollutants, however, underwent quick adsorption and electrochemical regeneration in minutes. In this study, binary and ternary GIC-based adsorbents were prepared using electrochemical intercalation of Chinese large flake graphite (CLFG) and Madagascan medium flake graphite (MMFG) materials. In this context GIC-bisulphate, GIC-nitrate, GIC-bisulphate-acetate, GIC nitrate-bisulphate, and GIC-nitrate-acetate were developed and characterized in order to evaluate their adsorptive and electrical properties. The adsorption behaviour was studied using an organic dye, acid violet 17, as a model dissolved organic pollutant. The treatment time and acid concentration for electrochemical intercalation were optimized in order to maximize the adsorptive capacity of the GIC based adsorbents. GIC-bisulphate delivered double adsorptive capacity after electrochemical intercalation, whereas, GIC nitrate diminished the adsorptive capacity to one half that of GIC bisulphate. However, no significant effect of ternary intercalated compounds was observed in terms of improved adsorption capacity or electrical conductivity.