Development and application of novel high throughput metal waste chips and foam electrodes for electrocoagulation treatment of graywater

ABSTRACT

In this study, novel high throughput metal waste chips and foam electrodes were developed for the electrocoagulation of graywater for the first time. The developed electrodes were then compared with traditional metal plate electrodes, which showed higher efficiency of developed electrodes. The effective parameters of pH, electrode distance, applied voltage, and reaction time on COD removal were optimized using RSM as a multivariate optimization technique, and the data were analyzed by ANOVA, normal plot, residual distribution, and 3D plots. The optimal conditions for electrocoagulation of graywater using metal (Al) plate electrode were determined as a pH of 6.86, electrode distance of 5 mm, and applied voltage of 5 V for a reaction time of 10 min, resulting in 89.1% COD removal and 74% turbidity removal. Finally, the performance of aluminum plate electrodes, foam electrodes, and electrodes made from metal waste chips was compared using COD removal efficiency as the index, revealing 84%, 93%, and 87% COD removal, respectively. These results demonstrated that the newly developed electrodes are suitable for graywater treatment with excellent COD removal efficiency, metal chip waste recycling, and cost-saving.

GRAPHICAL ABSTRACT

KEYWORDS:

• Aluminum foam electrode
• electrocoagulation
• metal waste chips electrode
• graywater treatment
• response surface method (RSM)

Data availability

The authors declare that the data supporting the findings of this study are available within the article and can be found at N. Sharaj Sharifi, 2019 [63].

Disclosure statement

No potential conflict of interest was reported by the author(s).