Biomaterial Database

Electrochemical treatment of aqueous wastes containing pyrogallol by BDD-anodic oxidation. 2009

Bensalah Nasr, and Trabelsi Hsen, and Gadri Abdellatif

Institut Supérieur des Sciences Appliquées et Technologie de Gabès, Université de Gabès, 6072 Zrig, Gabès, Tunisia. nasr.bensalah@issatgb.rnu.tn

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. This plant operates in a discontinuous mode by recirculating the waste continuously through a single-chamber electrochemical flow cell. The complete mineralization of pyrogallol and the electro-generated pollutants is obtained in the electrolytic device. HPLC analyses show the formation of carboxylic acids as the main intermediates. The efficiency of the electrochemical process was found to depend mainly on the pollutant concentration present in the waste and on the applied current density. The high efficiency of this technology can be explained in terms of the direct electro-oxidation at the BDD surface and the oxidation carried out by hydroxyl radicals and other electro-generated oxidants.

UI	MeSH Term	Description	Entries
D007202	Indicators and Reagents	Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)	Indicator,Reagent,Reagents,Indicators,Reagents and Indicators
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D010865	Pilot Projects	Small-scale tests of methods and procedures to be used on a larger scale if the pilot study demonstrates that these methods and procedures can work.	Pilot Studies,Pilot Study,Pilot Project,Project, Pilot,Projects, Pilot,Studies, Pilot,Study, Pilot
D004149	Dioxoles
D004563	Electrochemistry	The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.	Electrochemistries
D004566	Electrodes	Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.	Anode,Anode Materials,Cathode,Cathode Materials,Anode Material,Anodes,Cathode Material,Cathodes,Electrode,Material, Anode,Material, Cathode
D004572	Electrolysis	Destruction by passage of a galvanic electric current, as in disintegration of a chemical compound in solution.	Electrolyses
D013672	Technology	The application of scientific knowledge to practical purposes in any field. It includes methods, techniques, and instrumentation.	Industrial Arts,Arts, Industrial
D014865	Waste Disposal, Fluid	The discarding or destroying of liquid waste products or their transformation into something useful or innocuous.	Disposal, Fluid Waste,Disposals, Fluid Waste,Fluid Waste Disposal,Fluid Waste Disposals,Waste Disposals, Fluid
D018130	Diamond	Diamond. A crystalline form of carbon that occurs as hard, colorless or tinted isomeric crystals. It is used as a precious stone, for cutting glass, and as bearings for delicate mechanisms. (From Grant & Hackh's Chemical Dictionary, 5th ed)	Diamonds