Electro - Fenton processes for Landfill leachate treatment using different electrode materials

Abstract

Landfill leachate contains high concentration of pollutants and treatment of leachate is very challenging as the properties are very fluctuating with quantity and time. Due to presence of non-biodegradable pollutants advanced oxidation processes are found effective to treat landfill leachate. In this study, fresh leachate sample from Jambuva landfill site at Vadodara, Gujarat, India was collected and analysed for the initial characterization. Electro-Fenton process was applied for the treatment of landfill leachate to evaluate the COD removal and colour removal by two methods: i) An external ferrous source is added, and an oxygen-sparging cathode produces hydrogen peroxide., and ii) Using an oxygen-sparging cathode and a sacrificial anode, hydrogen peroxide and ferrous ion are electrogenerated. In the first method, Graphite was used as a cathode and Titanium as anode. In the second method, graphite was used as a cathode and Iron as anode. Continuous electro generation of hydrogen peroxide and Fe ions were measured to assess the efficiency of treatment process. In first method, maximum COD removal (58.22%) was obtained at current density 30 A/m2, FeSO4.7H2O dose of 1 mM and contact time of 150 mins with more than 98% colour removal. Whereas, in the second method, maximum COD removal (46.99%) was obtained at current density 40 A/m2 at contact time of 150 mins with more than 93% colour removal. The electro- Fenton process was found to be efficient for landfill leachate treatment.