Abstract
The treatment of tannery effluent is of great interest as it contains a complex mixture of pollutants, primarily chromium. The disposal of this wastewater can have adverse effects on the environment and aquatic life, which is an emerging problem for the environment. In this work, electrocoagulation is used to remove chromium from real tannery wastewater, focusing on performance optimization and sludge characterization. Electrocoagulation experiments were conducted using an electrochemical cell with iron electrodes immersed in a specific volume of tannery wastewater. Operating parameters, such as the initial chromium concentration, pH and current density as well as power consumption were evaluated to determine optimum chromium removal. The optimization was performed using Response Surface Methodology combined with central composite design. Analysis of variance (ANOVA) was used to determine the response, residual, probability, 3D surface and contour plots. The maximum chromium removal was 100% at the optimum values of 13 mA/cm2, 7 and 750 ppm for current density, pH and concentration, respectively.
Highlights
IntroductionChromium has several oxidation states, and each state has its own unique set of properties
Chromium has several oxidation states, and each state has its own unique set of properties.For example, the trivalent state of chromium (Cr(III)) is essential for carbohydrate metabolism in humans [1]; on the other hand, hexavalent chromium (Cr(VI)) is considered to be toxic [2]
The experimental results showed that the performance of EC in chromium removal is largely affected by the initial chromium concentration, current density and solution pH
Summary
Chromium has several oxidation states, and each state has its own unique set of properties. The trivalent state of chromium (Cr(III)) is essential for carbohydrate metabolism in humans [1]; on the other hand, hexavalent chromium (Cr(VI)) is considered to be toxic [2]. Is a hundred times more toxic than Cr(III), and it is more water soluble [3,4]. The toxicological concern for Cr(VI) stems from the fact that it is a strong oxidizing agent that can release free radicals that can have carcinogenic effects on cells [3]. Cr(VI) rarely exists in nature as an element; it is usually coupled with other elements to form compounds such as iron(II) chromite (FeCr2 O4 ).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
