Using Zeolite in the Ion Exchange Treatment to Remove Ammonia-nitrogen, Manganese and Cadmium

Municipal solid waste (MSW) landfill has generated leachate that causes a significant effect to the surface water and groundwater. The discharge of leachate into the water system must comply with the standards and regulations set by the Department of Environment (DOE), Malaysia. Therefore, it is important to treat the landfill leachate complying to those standards in order to protect the environment. In doing so, there have been many techniques developed to treat the landfill leachate and one of them is an ion exchange treatment having zeolite as its adsorbent. Therefore, this study evaluated the removal of ammonia-nitrogen and heavy metals (manganese and cadmium) using zeolite. The ability of zeolite to remove ammonia-nitrogen, manganese and cadmium as selective ion was also studied. Two media of samples were used. The first medium was synthetic leachate and the second was pre-treated leachate taken from Jeram Sanitary Landfill, Selangor. The experiment was conducted for five days in batch modes. The initial ammonia-nitrogen concentration of each medium was set to 20 mg/L, 40 mg/L, and 60 mg/L. It was found that the reduction of ammonia-nitrogen, manganese, and cadmium concentrations was 93%, 15% and 83% in synthetic medium, respectively. While in the pre-treated leachate sample, the reduction was in the order of 75%, 23%, and 86% for ammonia-nitrogen, manganese, and cadmium. The nitrification occurred in the batch culture experiment by supplying an additional aeration to the system. This was concurrently supported by the results of ammonia-nitrogen, which was reduced to nitrite-nitrogen and to nitrate-nitrogen in the pre-treated leachate sample. Hence, it is concluded that the nitrifying bacteria did exist in these batch experiments.