Phenol removal from wastewaters by electrochemical oxidation using boron doped diamond (BDD) and Ti/Ti0.7Ru0.3O2 dsa® electrodes

Abstract

-Industrial wastewater containing non-biodegradable organic pollutants consists of highly toxic effluents whose treatment is necessary due to environmental and economical restrictions. In order to treat these effluents, an electrochemical process using a dimensionally stable anode (DSA ® ) and boron-doped diamond (BDD) electrode was studied. The performance of these electrodes for COD removal from aqueous phenol solution was evaluated in the absence and presence of different chloride concentrations. The results showed that DSA ® could be successfully used to remove COD when high chloride concentration (3035 mg L -1 Cl -) and mild current density are employed (50 mA cm -2 ). On the other hand, the presence of chloride did not have the same significant effect on the COD depletion rate using BDD; however, under mild conditions (50 mA cm -2 , 0.190 m s -1 ), the addition of 607 mg L -1 Cl -improved the COD removal by approximately 52% after 8 hours of electrolysis. The effect of current density (i) and flow velocity (v) were also studied, and it was verified that they have an important role on the process performance, especially when DSA ® is used.

Treatment of petroleum refinery wastewater by electrochemical oxidation using graphite anodes

“…It is preferred to conduct further experiments at NaCl concentration of 2 g/L in which a complete removal of COD at the required level of phenol concentration discharge was achieved. Besides a negligible decrease in the energy consumption was observed at NaCl concentration higher than 2gl -1 also using higher concentration of NaCl may favor producing chlorinated organic compounds not destroyed by the anodic oxidation as proved by previous studies [38]. Similar trends were observed by Britto-Costa and Ruotolo [38] in the electrooxidation of phenol using BDD or DSA electrodes where COD removal increases with addition of NaCl.…”

“…Besides a negligible decrease in the energy consumption was observed at NaCl concentration higher than 2gl -1 also using higher concentration of NaCl may favor producing chlorinated organic compounds not destroyed by the anodic oxidation as proved by previous studies [38]. Similar trends were observed by Britto-Costa and Ruotolo [38] in the electrooxidation of phenol using BDD or DSA electrodes where COD removal increases with addition of NaCl. Souza and Ruotolo [19] studied the electrochemical oxidation of oil refinery effluent using boron-doped diamond anodes.…”

Application of Response Surface Methodology for Optimization of Phenol Removal from Simulated Wastewater using Rotating Tubular Packed bed Electrochemical Reactor

“…SnO2-Sb has short service life as well as deactivation problems [21]]. Using PbO2 as anode material could be led to further contamination of the wastewater with lead [22]. In spite of the high anodic stability of BDD as well as its wide potential window for discharging of water, it's using as anode for wastewater treatment is still limited due to its high cost [23].…”

Phenolic wastewater remediation employing nano zerovalent iron as a granular third electrode in an electrochemical reactor

“…People exposed to phenol acutely or chronically may suffer adverse health consequences, which may be quite serious depending on the degree of exposure [4]. Several techniques have been used to remove phenol from water and wastewater, including chemical oxidation [5,6], microbial degradation [7,8], membrane separation [9], photocatalytic degradation [10], solvent extraction [11], ultrasonic degradation [12], enzymatic polymerization [13], Fenton-like reactions [14], adsorption [15,16], and electrochemical oxidation [17,18].…”