Degradation of phenol using Co- and Co,F-doped PbO(2) anodes in electrochemical filter-press cells.
A comparative study on the electrooxidation of phenol in H(2)SO(4) medium using pure PbO(2) or F-, Co- and Co,F-doped PbO(2) electrodes in filter-press cells was carried out. The oxide films were obtained by galvanostatic electrodeposition using an electrolytic bath containing sodium lauryl sulfate as additive and Pb(2+), F(-), Co(2+) or Co(2+)+F(-), under magnetic stirring (to obtain 4-cm(2) electrodes) or ultrasound waves (to obtain 63-cm(2) electrodes). The best results were attained with PbO(2) electrodes doped with a low-Co content (1mM Co(2+) in the electrolytic bath) along with F(-): the chemical oxygen demand (COD) and the total organic carbon content (TOC) of the simulated wastewaters were removed by about 75% and 50%, respectively. When pure PbO(2) electrodes were used, the COD and TOC removals were about 60% and 45%, respectively. For the smaller electrodes, an average current efficiency (ACE) and an energy consumption (EC) of about 16% and 70 kWh kg(COD)(-1), respectively, were obtained. For the larger electrodes, the ACE and EC values were about 18% and 105 kWh kg(COD)(-1), respectively. Stability tests of the electrodes showed that they are suitable for use in the electrochemical treatment of phenol wastewaters.
Andrade
Leonardo S
LS
Departamento de Química, Universidade Federal de São Carlos, São Carlos, SP, Brazil.
Rocha-Filho
Romeu C
RC
Bocchi
Nerilso
N
Biaggio
Sonia R
SR
Iniesta
Jesús
J
García-Garcia
Vicente
V
Montiel
Vicente
V
D003035:Cobalt / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D005461:Fluorine / Q000737:chemistry*; D007854:Lead / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
D010087:Oxides; D010636:Phenols; D014874:Water Pollutants, Chemical; D005461:Fluorine; D007854:Lead; D003035:Cobalt; C047365:lead oxide