Background: Flocculation has been extensively used as a semi-aerobic landfill leachate treatment, prior to other treatment methods. Although inorganic and synthetic polymers are prominent in landfill leachate treatment, its application may introduce potentially toxic residual. As alternative to potential risk, starch based flocculant had been produced from durian seed waste. Plus, no attempt has been made to avail abundant waste of Durian Seed Starch (DSS) as a natural flocculant for wastewater and leachate treatment. In this paper, an attempt has been made to study the characterization performance of DSS in the flocculation process. Jar test results had ascertained that optimum pH and dosages values for DSS flocculant were pH 6 and 4000mg/L with removal of true colour and turbidity were 34% and 36.9% respectively. The scanning electron microscopy (SEM) images show the presence of contaminated particle layer on top of the DSS after the treatment process. The Fourier transform infrared spectroscopy (FTIR) analysis showed DSS was the major constituent of the floc. FTIR results verified that the agglomeration consist of leachate contaminants. Therefore, DSS could be a feasible selective flocculant in reducing the usage of inorganic polymer for semiaerobic landfill leachate treatment
