Electrochemical oxidation of p-hydroxybenzoic and protocathecuic acids at a dimensional stable anode (DSA) in the presence of NaCl.
This work is part of a wider research programme on innovative technologies for industrial wastewater treatment. Results from electrolyses at DSA commercial anodes of synthetic solutions with composition analogous to that of agro-industrial wastes are presented. The results obtained indicate that the rate of degradation of phenolic compounds is high, provided that chloride ions are present in solution. Oxidation of phenolic compounds is faster than that of biodegradable substances, such as sugars or amminoacids. Moreover, investigation on the trend of toxicity during the treatment, seems to exclude that toxic intermediates persist in solution when phenolic compounds are removed. Experiments on olive oil mill wastewater (OMW) samples show that the results obtained from synthetic solutions are extensible to real wastewater. When phenolic compounds are completely removed, the toxicity of the solution is very low; the initial dark colour of the solution, due to the brown pigment which characterises OMW, is nearly completely disappeared.
Polcaro
Anna Maria
AM
Dipartimento di Ingegneria Chimica e Materiali, Università di Cagliari, Piazza d'Armi, 09123 Cagliari. polcaro@dicm.unica.it
Mascia
Michele
M
Palmas
Simonetta
S
Vacca
Annalisa
A
D004563:Electrochemistry / Q000379:methods*; D062385:Hydroxybenzoates / Q000737:chemistry*; D007220:Industrial Waste; D000069463:Olive Oil; D010084:Oxidation-Reduction; D010226:Parabens / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry; D012965:Sodium Chloride / Q000737:chemistry; D014865:Waste Disposal, Fluid / Q000379:methods; D018508:Water Purification / Q000379:methods*
D062385:Hydroxybenzoates; D007220:Industrial Waste; D000069463:Olive Oil; D010226:Parabens; D010636:Phenols; D010938:Plant Oils; C009091:protocatechuic acid; D012965:Sodium Chloride; C038193:4-hydroxybenzoic acid