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This study evaluated the effectiveness of Fenton's technique for the treatment of semi-aerobic landfill leachate collected from Pulau Burung Landfill Site (PBLS), Penang, Malaysia. The Fe2+ or Fe3+ as catalyst and H2O2 as oxidizing agent are commonly used for the classical Fenton's reaction. In present study, the effect of operating conditions such as pH, reaction time, molar ratio, agitation rate, feeding mode and Fenton reagent concentrations which are important parameters that affect the removal efficiencies of Fenton method were investigated. Under the most favorable conditions, the highest removals of 58.1 and 78.3% were observed for COD and color, respectively. In general, the best operating conditions were pH = 3, Fe = 560 mg L(-1), H2O2 = 1020 mg L(-1), H2O2/Fe2+ molar ratio = 3, agitation rate = 400 rpm and reaction time = 120 minutes. The results highlighted that stepwise addition of Fenton's reagent was more effective than adding the entire volume in a single step. Excessive hydrogen peroxide and iron have shown scavenging effects on hydroxyl radicals and reduced degradation of refractory organics in the landfill leachate.

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Landfill leachate is one of the major contamination sources. In this study, the ability of synthetic ion exchange resins which carry different mobile ion for removing color, chemical oxygen demand (COD), and ammonia nitrogen (NH(3)-N) from stabilized leachate was investigated. The synthetic resin INDION 225 Na as a cationic exchanger and INDION FFIP MB as an anionic exchanger were used in this study. INDION 225 Na was used in hydrogen form (H(+)) and in sodium form (Na(+)), while INDION FFIP MB resin was used in hydroxide form (OH(-)) and in calcium form (Cl(-)) form. The results indicated better removal of color, COD and NH(3)-N by using INDION 225 Na in H(+) as compared with Na(+) form, while no performance differences were observed by using INDION FFIP MB in OH(-) or Cl(-) form. Applying cationic resin followed by anionic resin achieved 97, 88 and 94, percent removal of color, COD and NH(3)-N. The residual amounts were 160 Pt-Co, 290 mg/L and 110 mg/L of color, COD and NH(3)-N respectively.