Novel Electro-Fenton Approach for Regeneration of Activated Carbon

• Published in: Environmental science & technology Vol. 47; no. 14; pp. 7927 - 7933
• Main Authors: Bañuelos, Jennifer A, Rodríguez, Francisco J, Manríquez Rocha, Juan, Bustos, Erika, Rodríguez, Adrián, Cruz, Julio C, Arriaga, L. G, Godínez, Luis A
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 16.07.2013
• Subjects: Activated carbon; Adsorbents; Adsorption; Applied sciences; Carbon; Carbon - chemistry; Chemical reactors; Chemistry; Drinking water and swimming-pool water. Desalination; Electrocatalysis; Electrochemical Techniques; Electrodes; Exact sciences and technology; General and physical chemistry; General purification processes; Pollution; Surface physical chemistry; Wastewaters; Water treatment and pollution; Regeneration; Water treatment; Granular material; Activated carbon; Fenton reaction; Oxidation; Inorganic adsorbent; Electrochemical reaction
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es401320e

An electro-Fenton-based method was used to promote the regeneration of granular activated carbon (GAC) previously adsorbed with toluene. Electrochemical regeneration experiments were carried out using a standard laboratory electrochemical cell with carbon paste electrodes and a batch electrochemical reactor. For each system, a comparison was made using FeSO4 as a precursor salt in solution (homogeneous system) and an Fe-loaded ion-exchange resin (Purolite C-100, heterogeneous system), both in combination with electrogenerated H2O2 at the GAC cathode. In the two cases, high regeneration efficiencies were obtained in the presence of iron using appropriate conditions of applied potential and adsorption–polarization time. Consecutive loading and regeneration cycles of GAC were performed in the reactor without great loss of the adsorption properties, only reducing the regeneration efficiency by 1% per cycle during 10 cycles of treatment. Considering that, in the proposed resin-containing process, the use of Fe salts is avoided and that GAC cathodic polarization results in efficient cleaning and regeneration of the adsorbent material, this novel electro-Fenton approach could constitute an excellent alternative for regenerating activated carbon when compared to conventional methods.