Potential of Mangrove barks for Removal of Heavy Metal Ions from Wastewater Mohd Jain Nordin Mohd Kassim, Rozaini Che Amat and Oo Chuan Wei School of Chemical Sciences, Universiti Sains Malaysia E-mail: [email protected] Abstract The barks of Rhizophora apiculata has been utilized as an adsorbent for the removal of heavy metal ions from wastewater. The barks were modified by polymerizing it using formaldehyde in acidic condition. Adsorbent parameters such as effect of pH, adsorbent dosage, initial concentration and contact time have been studied to evaluate the performance of the adsorbent for removal of Cu(II) and Ni(II). The heavy metal ions removal were rapidly established in about 30 min and the maximum removal was 80 % for Cu(II) and 70 % for Ni(II), both at pH 5. The Langmuir and Freundlich adsorption isotherm models were well fitted to equilibrium adsorption data for both metal ions. Monolayer adsorption capacities for Cu(II) and Ni(II) were obtained as 4.10 mg/g and 0.88 mg/g, respectively. The removal of the studied metal ions was found to follow the pseudo second order kinetic reaction. Keywords: Adsorption, Bark, Heavy metals, Isotherm, Kinetic.