ABSTRACT
The present study is carried out to remove chromium and turbidity from tannery wastewater using the electrocoagulation process with aluminum electrodes. This experimental study is carried out using a batch system. The applied pilot comprises a reactor containing two parallel metal electrodes (Al). The latter are connected as monopolar, and a different potential is applied between them. Several working parameters, such as applied potential difference, electrolysis time, active electrode surface, interelectrode distance, and the pH of the medium have been studied to achieve higher removal efficiency. The treatment reached a maximum reduction of 99% for turbidity and 93% for chromium under the following conditions: 15 V applied potential difference, 45 cm2 electrode surface, 1 cm interelectrode distance, pH 6.1 raw water, and a contact time of 90 min. Given the treatment efficiency obtained in this study, electrocoagulation process has the potential to be used for the cost-effective removal of wastewater pollutants.
Subject(s)
Chromium/isolation & purification , Electrocoagulation/methods , Tanning , Waste Disposal, Fluid/methods , Chromium/analysis , Electrocoagulation/instrumentation , Electrodes , Equipment Design , Hydrogen-Ion Concentration , Waste Disposal, Fluid/instrumentation , Wastewater/chemistry , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/isolation & purificationABSTRACT
Water remediation by adsorption of the metal ions on a low cost sorbent is the frame of the present study. The metal ions adsorption properties of sawdust of palm tree fronds (PTF sawdust) are investigated by both equilibrium measurements and modified carbon paste electrode. The ability to adsorb Cu(II), Cr(VI) and As(III) in significant quantities is demonstrated. Carbon paste electrodes modified by incorporation of PTF sawdust (PTF-CPE) or, for comparison, an organically modified silica for the detection of copper(II) are investigated in term of sensitivity, estimation of number of possible reuses, repeatability and interference effect. A detection limit for Cu(II) analysis of 1.0×10(-8) M has been achieved after 5 min preconcentration and a single PTF-CPE can be used for up to 10 preconcentration-analysis-regeneration cycles. The relative standard deviation (n=9) for the determination of a 10(-6) M Cu(II) solution (pH=5) was about 26%. The effects of Ca(II), As(III) and Cr(VI) on the copper detection are investigated: calcium ions were shown to compete with copper on the same adsorption sites, arsenic(III) has no effect on the copper detection whereas chromium(VI) was shown to enhance the copper detection.
