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.
