Factorial design and optimization of thermal activation of persulfate for stabilized leachate treatment

Landfill remains as the most common municipal waste disposal method in the world. However, the production of leachate associate with landfill persists as a major drawback, which bring harmful effect to the environment. Persulfate oxidation is recently used for stabilized leachate treatment. Persulfate alone is still limited for leachate oxidation and an activation method is required to improve its performance. Accordingly, this study aims to investigate and compare the performance of per sulfate subjected to thermal activation in treating stabilized leachate. Different experimental operational factors were considered and evaluated such as, S2O82-/chemical oxygen demand (COD) ratio, temperature, and reaction time. Experiments were designed and optimized by using response surface methodology, and results were analysed by using analysis of variance. The removal efficiencies for COD and colour using inactivation persulfate were reported only at 14% and 29%, respectively. However, the efficiencies were improved to 93.39% and 94.00% for COD and colour after thermal activation of persulfate under an optimum condition of 10 S2O82-/COD ratio, 80 degrees C and 120 min. The maximum efficiency was achieved at the treatment cost of RM0.66 per litre of leachate.

Automated summary

This study aims to investigate and compare the performance of thermally activated persulfate in treating stabilized leachate. By optimizing experimental operational factors such as S2O82-/COD ratio, temperature, and reaction time, it was found that the efficiency of persulfate oxidation for COD and colour removal significantly improved after thermal activation.