Nitrate and carbon matter removals from real effluents using Si/BDD electrode.
This work investigated the electrochemical treatment of four real effluents which were municipal wastewater (MWW), human urine (HU), river water (Wadi), and slaughterhouse wastewater (SHWW). The treatment was performed on a Boron-Doped Diamond (BDD) as anode/cathode material with an applied current density of 35.7 mA cm-2and without any reagent addition. Effluent characterization before treatment indicated that nitrogen pollution existed essentially as ammonium/ammonia ions, low level of nitrate, and in some cases as nitrite form. Organic pollution was also determined by COD values which were 920, 7300, 320, and 2280 mg O2L-1for MWW, HU, Wadi, and SHWW effluents, respectively. The effectiveness of the electrochemical oxidation/reduction was assessed by nitrogenous compounds and COD removals. Obtained removals underlined the simultaneous oxidation and reduction at the BDD interfaces of the main species present in the real effluents as well as the electro-generated ones. Results confirmed the high performance of BDD electrode for removal of coexistent pollutants from the studied matrix. The oxidation of organic matter and ammonium/ammonia as well as the kinetic of COD degradation was rapid in acidic medium (HU case) than that in neutral and alkaline medium (MWW, Wadi, and SHWW). Moreover, the phytotoxicity test showed less toxic behavior only in the cases of MWW and SHWW with a Germination Index equal to 58.8 and 72.2 %, respectively. The EC and ACE were also evaluated for all studied wastewaters, and the lowest EC value (0.03 kWh (g COD)-1) was obtained for the more charged effluent (HU).
Laboratory of Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE), Techopark Borj Cedria, Touristic road of Soliman, BP 273, 8020, Soliman, Tunisia.
Mouna
M
Ghazouani
Laboratory of Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE), Techopark Borj Cedria, Touristic road of Soliman, BP 273, 8020, Soliman, Tunisia. hanene.akrout@yahoo.com.
Hanene
H
Akrout
Laboratory of Wastewaters and Environment, Centre of Water Researches and Technologies (CERTE), Techopark Borj Cedria, Touristic road of Soliman, BP 273, 8020, Soliman, Tunisia.
Latifa
L
Bousselmi
D001895:Boron / Q000737:chemistry*; D002244:Carbon; D018130:Diamond / Q000737:chemistry*; D004566:Electrodes; D010084:Oxidation-Reduction; D014874:Water Pollutants, Chemical
D014874:Water Pollutants, Chemical; D002244:Carbon; D018130:Diamond; D001895:Boron
BDD electrode; Electrochemical treatment; Kinetic; Phytotoxicity test; Real effluent