Physico-chemical removal of colour and iron from anaerobic landfill leachate by zeolite and limestone-Batch experiments

Leachate generated from one of the old landfills in Malaysia was characterized. Colour, and iron was found in significant amount. The ability of limestone, zeolite and their mixtures as filter media to attenuate colour and total iron from anaerobic leachate was investigated in this study. Influence of shaking speed and contact time was studied. The kinetic study, Langmuir and Freundlich adsorption isotherms parameters were determined. The result indicated that more than 75% of colour and 95% of iron were removed by zeolite or a mixture of both media at mixing ratio 25:15 (limestone : zeolite, by volume) while only 38% of colour and 95 of iron were removed by limestone. The result show that the mixed media exhibited better technical and economical results for both parameters as compared with the use of the individual media.