Towards sustainable removal of methylthioninium chloride by using adsorption-electroradical regeneration.

The current need for effective regeneration processes to be used in valorization of spent adsorbent demands the research of novel alternative techniques such as application of Advances Oxidation Processes. In this sense, the recent application of electroradical (ER) processes turned out to be very promising in terms of the drugs degradation from different environments. Thus, in this study, harnessing of a low cost natural adsorbent, Tunisian bentonite (BE), was evaluated for the removal of a model drug such as methylthioninium chloride (MC), and then its regeneration by ER processes was demonstrated.

Electrochemical treatment of aqueous solutions of organic pollutants by electro-Fenton with natural heterogeneous catalysts under pressure using Ti/IrO-TaO or BDD anodes.

The treatment of toxic organic pollutants by electro-Fenton (EF) presents some drawbacks such as the necessity to work at low pH and the low solubility of oxygen in water contacted with air or oxygen at room pressure that results often in slow and relatively low abatements. Here, the coupled adoption of natural heterogeneous catalysts and of relatively high pressure was proposed in order to improve the performances of EF for the treatment of organic pollutants. Caffeic acid (CA) and 3-chlorophenol were used as model resistant organic pollutants.

Electro-Fenton oxidation of reverse osmosis concentrate from sanitary landfill leachate: Evaluation of operational parameters.

The electro-Fenton oxidation of a concentrate from reverse osmosis of a sanitary landfill leachate, with an initial chemical oxygen demand (COD) of 42 g L, was carried out using a carbon-felt cathode and a boron doped diamond anode. The influence of the applied current intensity, initial pH and dissolved iron initial concentration on the electro-Fenton process was assessed. For the experimental conditions used, results showed that the initial pH is the parameter that more strongly influences the current efficiency of the electro-Fenton process, being this influence more pronounced on the oxidation rate than on the mineralization rate of the organic matter.

Electrochemical treatment of concentrate from reverse osmosis of sanitary landfill leachate.

Conventional sanitary landfill leachate treatment has recently been complemented and, in some cases, completely replaced by reverse osmosis technology. Despite the good quality of treated water, the efficiency of the process is low and a large volume of reverse osmosis concentrate has to be either discharged or further treated. In this study, the use of anodic oxidation combined with electro-Fenton processes to treat the concentrate obtained in the reverse osmosis of sanitary landfill leachate was evaluated.

Pyrite as a sustainable catalyst in electro-Fenton process for improving oxidation of sulfamethazine. Kinetics, mechanism and toxicity assessment.

The degradation of 0.20 mM sulfamethazine (SMT) solutions was investigated by heterogeneous electro-Fenton (EF) process using pyrite as source of Fe(2+) (catalyst) and pH regulator in an undivided electrochemical cell equipped either with a Pt or a BDD anode and carbon-felt as cathode. Effect of pyrite concentration and applied current on the oxidative degradation kinetics and mineralization efficiency has been studied.

Electrochemical mineralization of the antibiotic levofloxacin by electro-Fenton-pyrite process.

Levofloxacin is a large spectrum antibiotic from fluoroquinolones family, widely used and detected in natural waters. Here, this drug was degraded by a novel heterogeneous electro-Fenton (EF) process, so-called EF-pyrite, in which pyrite powder in suspension regulates the solution pH to 3.0 and supplies 0.

Treatment of aqueous wastes contaminated with Congo Red dye by electrochemical oxidation and ozonation processes.

Synthetic aqueous wastes polluted with Congo Red (CR) have been treated by two advanced oxidation processes: electrochemical oxidation on boron doped diamond anodes (BDD-EO) and ozonation under alkaline conditions. For same concentrations, galvanostatic electrolyses have led to total COD and TOC removals but ozonation process can reach only 85% and 81% of COD and TOC removals, respectively. UV-vis qualitative analyses have shown different behaviors of CR molecules towards ozonation and electrochemical oxidation.

Electrochemical treatment of aqueous wastes containing pyrogallol by BDD-anodic oxidation.

In this work, the electrochemical oxidation of pyrogallol (1,2,3-trihydroxybenzene) on boron-doped diamond anodes has been studied. The voltammetric results showed that pyrogallol oxidation takes place in the same potential region as that of phenol where the supporting electrolyte is stable. Synthetic wastewaters containing pyrogallol have been treated in a bench-scale electrolysis plant.

Electrochemical oxidation of hydroquinone, resorcinol, and catechol on boron-doped diamond anodes.

The electrochemical oxidation of aqueous wastes polluted with hydroquinone, resorcinol, or catechol on boron-doped diamond electrodes has been studied. The complete mineralization of the organic waste has been obtained independently of the nature of each isomer. No aromatic intermediates were found during the treatment, and solely aliphatic intermediates (carboxylic acids C4 and C2, mainly) were detected in the three cases.

Fenton treatment of olive oil mill wastewater--applicability of the method and parameters effects on the degradation process.

The low biodegradability of polyphenolic compounds typically found in olive processing indicated that biological treatment is not always successful in the treatment of olive oil mill wastewater in term of COD removal. In this study the results of investigations on the applicability of Fenton's reagent in the treatment of this effluent were discussed. The efficiency of this method was determined.