Enhanced reducing leachate pollution index through electrocoagulation using response surface methodology

• Published in: Heliyon 2024-09, Vol.10 (18), p.e38134, Article e38134
• Main Authors: Ameli, Fateme, Hashemi, Hassan, Samaei, Mohammad Reza, Asgari, Esrafil, Mohammadian Fazli, Mehran
• Format: Article
• Language: English
• Subjects: Central composite design; Electrocoagulation; Leachate pollution index; Response surface methodology
• ISSN: 2405-8440; 2405-8440
• DOI: 10.1016/j.heliyon.2024.e38134

Addressing the urgent need to effectively manage landfill leachate as a harmful flow for human health and the environment, this research investigates how electrocoagulation (EC) processes could alleviate the pollution potential of leachate. So far, no experimental study has been carried out on reducing the leachate pollution index (LPI) under the EC process. For this purpose, in this novel research, the LPI was utilized as a key metric to evaluate the efficiency of the treatment process. Central Composite Design (CCD) as a subset of Response Surface Methodology (RSM) was applied to enhance the LPI parameters decreasing percentage. The data were analyzed by analysis of variance and multivariate regression and 3D plots assessed variable interactions. Under optimal conditions, it showed removal of 97.48 % for COD, 91.42 % for BOD5, 98.52 % for N-NH3, and 91.6 % for TDS. Significant reductions were observed in 94.81 % TKN, 87.20 %, 82.80 %, 96.66 %, and 99.28 %, 99.18 %, and 96.56 % for TKN, Cl−, CN−, As, Cr, Zn, and Ni, respectively. Moreover, the kinetics of COD removal indicated that it follows a first-order model. Thus, based on experimental results, the LPI of raw leachate decreased from 38.06 to 7.22 (81 % decrease) under the EC treatment method. The study indicated that the EC treatment method successfully reduced leachate pollution and met the leachate discharge standard. [Display omitted] •The leachate pollution index was used as a criterion to assess the effectiveness of the EC process.•Response surface methodology was utilized to model responses and optimize treatment processes.•Three-dimensional response surface plots were interpreted to visualize the interactions between different parameters and their effects on the removal efficiency.•Electrochemical mechanisms, reaction kinetics, and operating cost of the EC process were studied.•The study reported significant removal of leachate pollution index parameters such as COD, BOD5, N-NH3, and TDS.