Reduction of Total Chromium Levels from Raw Tannery Wastewater via Electrocoagulation using Response Surface Methodology
 
More details
Hide details
1
Universidad de Lima, Instituto de Investigación Científica (IDIC), Av. Javier Prado 4600, Surco, Lima, Perú
2
Centro de Innovación Productiva y Transferencia Tecnológica del Cuero, Calzado e Industrias Conexas (CITEccal Lima) - ITP, Av. Caquetá 1300, Rímac, Lima, Perú
CORRESPONDING AUTHOR
Edwar Aguilar-Ascón   

Universidad de Lima, Instituto de Investigación Científica (IDIC), Av. Javier Prado 4600, Surco, Lima, Perú
Publish date: 2019-12-01
 
J. Ecol. Eng. 2019; 20(11):217–224
KEYWORDS
TOPICS
ABSTRACT
This study focused on reducing total chromium levels in raw wastewater from the leather tanning industry via electrocoagulation to comply with maximum permissible limits (MPL) and to determine the effects of main process parameters. An electrocoagulation reactor was built using aluminum electrodes as an anode and cathode. Then, the response surface methodology was applied using a 3k factorial design considering three factors, namely current intensity, treatment time, and pH. The total chromium removal percentage was considered as a response variable. 99% of the total chromium found in wastewater could be removed after 14-min treatment at 2-A current intensity and pH 5.5. Similar amount of chromium was removed at pH of 8.5 and 7. Statistical analysis performed at a confidence level of p < 0.05 revealed that all three factors influenced electrocoagulation. Total chromium could be efficiently removed from raw wastewater at a current intensity of 2.9 A, a pH of 8.4, and a treatment time of 21 min, suggesting that electrocoagulation using aluminum electrodes is an efficient method for total chromium removal. Thus, this process must be considered as a solution to the problems caused by the leather tanning industry and for better compliance with the MPL established in the Peruvian environmental standards.