Removal of Heavy Metals (Fe and Pb) in The Mahakam River Water Using Eggshells and Rubbing Ash as Adsorbent

Abstract

Pollution of heavy metals (Fe and Pb) in the Mahakam River water has become an important problem. The solution for this case is water purification using natural product. There are several purification methods, one of them is the adsorption method to reduce the levels of heavy metals (Fe and Pb). The aim of this study was to reduce the concentration of heavy metals (Fe and Pb) using egg shells and rubbing ash as adsorbents. Characterization of the ability to adsorb heavy metals by adsorbents using Atomic Absorption Spectroscopy (AAS). By varying the mass of the adsorbent, the maximum Fe adsorption ability was obtained at a mass of 10 grams, namely 0.11 mg per liter (eggshells) and 0.3 mg per liter (eggshells+rubbing ash). Meanwhile, the maximum Pb adsorption capacity at 10 grams was 0.24 mg per liter (eggshells) and 0.17 mg per liter (eggshells+rubbing ash). Thus the best adsorbent for Fe is eggshell and the best adsorbent for Pb is a mixture of eggshell and rubbing ash. For modelling Fe sorption by eggshells, the Freudlich isotherm fits better than the Langmuir isotherm. Based on the Freudlich isotherm result, the adsorption process is forable and the maximum adsorption capacity is 0.009601 mg/g. This work gives detailed information about an innovative method to utilize eggshell waste and rubbing ash as an inexpensive adsorbent to remove heavy metals (Fe and Pb) from Mahakam River Waters.