Simultaneous removal of acidity and lead from acid lead battery wastewater by aluminum and iron electrocoagulation

Abstract

In this work the performance of electrocoagulation in the treatment of acid lead battery manufacturing wastewater was studied. Both iron and aluminum sacrificial electrodes remove lead effectively. However, pH of the treated wastewater depends on the electrode material and the supporting electrolyte used. Iron electrocoagulation with KCl as supporting electrolyte reduces the initial Pb 2+ ion concentration of 8.6 mg L-1 to 0.2 mg L-1 in 20 minutes of electrolysis time. At the same time, however, the initial wastewater pH of 2.96 rises sharply to 12.24 exceeding by far the upper legal limit for effluent discharge to the environment. On the contrary iron electrocoagulation with Na 2 SO 4 as supporting electrolyte does not increase pH sufficiently to the appropriate range. Aluminum treatment with KCl and Na 2 SO 4 electrolytes need 35 minutes of electrolysis time for effective lead removal. Effective removal of both, acidity and lead in a single step was achieved in only 25 minutes of electrolysis time with iron electrodes and a mixed supporting electrolyte solution containing 0.03 M Na 2 SO 4 and 0.003 M KCl.

ADSORPTION CAPACITY OF CARBONIZED TITONIA DIVERSIFOLIA TOWARDS Cd2+ AND CU2+ UNDER DIFFERENT pH, ADSORPTION CAPACITY AND CONCENTRATION

“…The increase in the removal of copper as pH increases is due to the decrease in competition between proton and Cu 2+ ion for the surface site. At low pH, the hydrogen ion competes with the metal cations for the exchange sites in the system which partially releases the metal cations [17].…”

Innovative Recovery of Winemaking Waste for Effective Lead Removal from Wastewater

“…The assay conditions were: 6 h contact time, 20 mg/L Pb 2+ initial concentration, and 1 g/L adsorbent amount. The 20 mg/L Pb 2+ concentration was chosen due to the fact that this value is close to the Pb concentration in the wastewater released by lead battery manufacturing or recycling industries [19]. During the experiment, the pH was measured and adjusted with HNO 3 or NaOH solutions (if necessary) so that the variation did not exceed ±0.5 units compared to the defined value.…”

“…The spectra attained for each type of grape-marc are The pH level was regularly verified during the contact time, and it was adjusted to the required value (maximum variation permitted was ±0.5 units) by small additions of base or acid solutions. As Pb precipitation easily occurs for pH levels higher than 6.0 (especially for concentrated solutions) and since real effluents, contaminated with lead, present an acidic pH, either mining wastewater [27] or industrial polluted waters from lead battery manufacturing or recycling industries [19,28], the pH effect was studied only in the interval between 2 and 5.5. The results represented in Figure 5 indicate that the pH augmentation leads to an increase in Pb uptake from extremely low values for pH 2, up to 97% for pH 5.5 (SbE).…”

Validity of Egyptian Na‐montmorillonite for adsorption of Pb2+, Cd2+ and Ni2+ under acidic conditions: characterization, isotherm, kinetics, thermodynamics and application study

“…[18] The optimum pH was found to be 7; however, further removal experiments were performed under acidic condition (pH 3.8) where one aim of the present study is to evaluate the potential of the Egyptian Na-MMT to remove the toxic metals under the acidic conditions of wastewater (e.g. wastewater of battery factories that normally has pH less than 4 [19,20] ).…”