Investigating the Electrocoagulation Treatment of Landfill Leachate by Iron/Graphite Electrodes: Process Parameters and Efficacy Assessment

Electrocoagulation is a widely used method for treating leachate since it is cost effective and eco-friendly. In the present study, the electrocoagulation process was employed to remove chemical oxygen demand (COD), NH4+, total dissolved solids (TDS), total suspended solids (TSS), turbidity, and color from landfill leachate. At first, lime was used as a pretreatment, then the Fe/Gr and Ti/PbO2/steel electrodes were used, and the optimum electrode was selected. Afterwards, the effects of some variables, including pH, current density, temperature, the inter-electrode distance, and the type of electrolyte were investigated. Results showed that COD, NH4+, TSS, TDS, electrical conductivity (EC), turbidity, color, and pH of effluent pretreatment chemical reached 22,371, 385, 884, 21,820 (mg/L), 13.8 (ms/cm3), 1355 (NTU), 8500 (TCU) and 10, respectively (the removal efficiency was 0, 20.37, 32.4, 61.99, 59.18, and 56.6 percent). With the Fe/Gr electrode, the optimal condition was observed as follows: pH of 7.5, current density of 64 mA/cm2, inter-electrode distance was equal to 1.5 cm, temperature at 20 °C, and retention time 2–4 h. Overall, the electrocoagulation with the Fe/Gr electrode was a suitable technology for landfill leachate treatment due to its effectiveness for the removal of both COD and NH4+, with advantageous performance indicators.

Statistical Modelling of a Comparative Phytotoxicity Study of Treated Yellow 10Gw Dye Solution With Copper and Aluminum in Electrocoagulation Process

This work was carried to compare the efficiency of Cu and Al electrodes in the elimination of Yellow 10 gw dye solution with the optimization of operative factors such as pH, NaCl, contact time, and current density in the electrocoagulation method. Analysis of variance (ANOVA) was used to assess the impact of these variables, with significance set at P<0.05. The data was statistically examined with Origin2021 and SPSS software, and significant differences between mean values were determined using analysis of variance (ANOVA). For each experiment, duplicates were kept, and the efficiency of Yellow 10 gw dye solution for those parameters was derived using analysis at a 5% level of significance. The utility of treated dye solutions using both the electrodes was tested on V.radiata in terms of germination percentage, root, and shoot length with distilled water as control. For all of the qualities examined, significant disparities were found among entries. The dye solution used with Al resulted in much higher germination (100%), root length (9.72 cm), and shoot length (24.5 cm).

Phenol removal by enhanced electrocoagulation process with persulfate salt

Introduction. Phenol is classified as priority pollutant. Phenol and its derivatives are stable in water, environmental contamination, and health concerns that are used as raw material in many chemical industries. This study investigated the removal of phenol by the reactivity of free sulfate radicals (SO4•–), activated by electrochemically generated Fe2+/Fe3+ ions which furthermore are evaluated to destroy phenol in aqueous solution. Materials and methods. In the present experimental study, electrocoagulation reactor by iron electrodes is used in the pre­sence of persulfate ions to phenol removing from aqueous solutions. In this regard, the effect of four independent variables including pH, electric current, persulfate dosage, and initial phenol concentration were studied on phenol removal. Results. The study determined the optimum conditions for maximum phenol removal using electro-persulfate process (EPS) as pH 3, 7.4 mM persulfate dosage, 27.78 mA/cm2 current density, and 100 mg/L initial phenol concentration at 30-min reaction time. The results showed that the efficiency of phenol removal was directly related to the initial persulfate dosage. In addition, the pH values, less than the phenol pKa, has slight effect onto the phenol removal. However, it was inversely correlated with a highly alkaline pH and higher phenol concentration. Conclusions. The study concluded that electro-persulfate process is an effective and robust process that can be used for handling of phenol containing wastewater.

Pengaruh Waktu Proses pada Desalinasi Air Laut dengan Metode Elektrokoagulasi secara Batch

ABSTRAK Salah satu upaya untuk menjaga persediaan air yaitu dengan cara menurunkan parameter air laut agar memenuhi parameter air tawar menggunakan metode elektrokoagulasi. Penelitian ini bertujuan untuk mempelajari pengaruh waktu proses elektrokoagulasi terhadap penurunan TDS, kekeruhan, kadar Cl, dan kadar Fe. Selain itu, untuk mengetahui perbandingan antara elektroda Al dan Fe. Air laut diambil dari Pantai Pelabuhan Ratu. Elektroda yang digunakan adalah Al dan Fe dengan ukuran 15x10 cm2. Tegangan yang digunakan yaitu 5 volt atau rapat arus sebesar 0,137 A/dm2 dengan waktu proses 15, 30, 45, dan 60 menit serta volume bahan bakunya 4 Liter. Penelitian dengan waktu proses 30 menit dan proses pengendapan selama satu hari mampu menurunkan kekeruhan hingga 2,28 NTU (55,07%); TDS hingga 1.010 mg/L (3,71%); kadar Cl hingga 271,98 mg/L (3,52%); dan kadar Fe 0,05 mg/L (40,65%). Proses elektrokoagulasi menggunakan elektroda aluminium lebih baik dibandingkan elektroda besi pada waktu proses 30 menit. ABSTRACT One of the efforts to maintain water supply is by lowering seawater parameters to meet freshwater parameters using the electrocoagulation method. This study aims to study the effect of electrocoagulation process time on the decrease in TDS, turbidity, Cl content, and Fe content. In addition, to determine the comparison between Al and Fe electrodes. Seawater is taken from Pelabuhan Ratu Beach. The electrodes used are Al and Fe with a size of 15x10 cm2. The voltage used is 5 volts or a current density of 0,137 A/dm2 with processing times of 15, 30, 45, and 60 minutes and the volume of the raw material is 4 liters. Research with a processing time of 30 minutes and sedimentation for one day was able to reduce turbidity up to 2,28 NTU (55,07%); TDS up to 1.010 mg/L (3,71%); Cl content up to 271,98 mg/L (3,52%); and Fe content of 0,05 mg/L (40,65%). The electrocoagulation process using aluminum electrodes was better than iron electrodes at a processing time of 30 minutes.