Anodic, cathodic and combined treatments for the electrochemical oxidation of an effluent from the flame retardant industry

Abstract

The electrochemical oxidation of an effluent from the manufacture of phosphorus based flame retardants was studied. To reach a residual concentration of reduced phosphorus lower than 10 mg L-1, in compliance with Italian law for industrial wastewater disposal, anodic oxidation using a boron-doped diamond (BDD) anode and electro-Fenton (EF) treatment were tested. The effects of some factors are optimised and a comparison of the reaction pathways is also presented. A combined treatment using EF with BDD conducted in an undivided cell is shown not to enhance the data obtained with BDD while a novel combined treatment using EF and BDD in a divided cell shows promising results when an anionic membrane is used as separation. In this last case the cell operates as two different batch reactors working with the same current. The anodic compartment, fed with raw effluent, provides partial oxidation, while the cathodic compartment, fed with the partially anodically oxidised solution, completes the treatment. When the effluent is transferred in the cathodic compartment, the anodic one is fed with fresh untreated solution. The advantage of this kind of coupling consists in the simultaneity of the two treatments which allows total oxidation with notable saving of charge and time

On the ability to electrogenerate hydrogen peroxide and to regenerate ferrous ions of three selected carbon-based cathodes for electro-Fenton processes

“…The development of an electrochemical process capable of producing the Fenton reagent at selected cathodes has overcome the main drawbacks represented by the need of notable amounts of reagents and the overproduction of iron-containing sludge. Due to the results obtained, this technology has experienced a fast development and its applications over the years have ranged from treatment of dyes [4][5][6], pesticides [7,8] herbicides [9], explosives [10], surfactants [11], drugs [12,13], real effluents [14][15][16] and spent adsorbent regeneration [17].…”

Sonoelectro-Fenton process: A novel hybrid technique for the destruction of organic pollutants in water

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Electrochemical Advanced Oxidation Processes: An Overview of the Current Applications to Actual Industrial Effluents

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