Kemampuan Kulit Buah Kakao (Theobromacacao) Sebagai Biosorben Ion Logam Hg(II) dan Ni(II)

Abstract

Thebiosorption of Hg (II) and Ni (II) ions has been investigated using the peels of cacao (Theobroma cacao) with variation of contact time, pH, and concentration. Concentrations of Hg (II) and Ni (II) ions before and after biosorption were determined using by Spectrophotometer UV-Vis. Determination of isotherm adsorption pattern of Hg and Ni metals using Langmuir and Freundlich adsorption isotherms.The results showed that the peels of cacao (Theobroma cacao) was able to adsorp Hg (II) and Ni (II) ions and the optimum adsorption occurred at 90 minutes contact time for Hg (II) ion with 97.96% uptake and 20 min for Ni (II) ions with an absorption rate of 8.2 mg/gram at pH 5. The adsorption isotherm pattern follows the Langmuir and Freundlich isotherms but tends to isotherm Langmuir. The functional groups involved in the biosorption of Hg (II) and Ni (II) ions by the peels of the cacao (Theobroma cacao) are the -OH and N-H groups.