OPTIMASI WAKTU KONTAK DAN KONSENTRASI ION Cr(VI) MENGGUNAKAN LEMPUNG ALAM MAREDAN

Abstract

Maredan natural clay is a local potential that has been widely utilized as an adsorbent material because it has a high silica and alumina contents. Maredan natural clay is utilized as an adsorbent material in the adsorption process to adsorb Cr(VI) metal ions. The purpose of this study was to determine the adsorption efficiency, determine the adsorption isotherm and kinetics model as well as the regeneration ability of Maredan natural clay. The method used in this research is adsorption method. The parameters used in this study are contact time and adsorbate concentration. In the contact time the variations made are 10, 20, 30, 40 and 50 minutes, while in the adsorbat concentration the variations made are 25mg/L, 50mg/L, 100mg/L, 150mg/L, and 200mg/L. Regeneration uses a desorption solution of 1 M HCl. Characterization of Maredan natural clay using Fourrier Transform Infra-Red (FTIR) to show the functional groups of Maredan natural clay. The results of Maredan clay analysis using FTIR have several groups such as Si-OSi, Si-O-Al, Al-O and -OH on Maredan clay before adsorption. Optimum parameters in adsorbing Cr (VI) ions were obtained at a contact time of 40 minutes and 50 mg/L with an adsorption efficiency of 60.67% and an adsorption capacity of 1.4153 mg/g. The adsorption kinetics model follows the second-order pseudo with R2 = 0.9994. The adsorption isotherm model follows the Langmuir isotherm with R2 = 0.9928 which indicates the adsorption is homogeneous and monolayer.