Abstract:
This study aims to analyze the adsorption ability of white jabon fruit (Anthocephalus
cadamba Miq.) on lead ions and the regeneration ability of white jabon fruit carbon and
determine the isotherm model and adsorption kinetics. White jabon fruit carbon is made
by carbonization at 300˚C for 30 minutes. The carbon will reach equilibrium so it is
regenerated with 1 M HCl to restore the adsorption ability of the carbon. The yield of
carbon was 65.5262%. The surface area of the carbon is 90.4858 m2/g. Carbon
characterization results based on SNI No. 06-3730-1995 obtained a water content of
2.23%; ash content 4.30%; adsorption capacity of iodine 1007.1256 mg/g and adsorption
capacity of methylene blue 24.4077 mg/g. Optimum conditions were obtained at pH 6,
contact time 40 minutes and adsorbate concentration of 40 mg/L with adsorption
efficiency of 99.41% and adsorption capacity of 1.6300 mg/g. The percentage of
regeneration reached 89.71%. The pH of pzc obtained in this study was at a pH of around
5 which indicates that charcoal is negatively charged at an optimum pH of 6.. The FTIR
results showed the functional groups N-H, C-H aliphatic, C-H aromatic, C=O, C-O-C and
O-Pb. The SEM-EDS results showed differences in the surface of the carbon before
adsorption, after adsorption and after regeneration with the contents of the carbon
elements C, N, O, Na, Cl, K and Pb. The BET results showed that the largest surface area
was obtained by carbon before adsorption, namely 0.2885 m2/g. The adsorption isotherm
model follows the Langmuir isotherm with the equation y = 0.0665x + 0.1582 and the
determination value R2 = 0.9061 which indicates that the adsorption on the surface is
homogeneous and has a single layer or monolayer. The adsorption kinetics follows a
pseudo-second order with the equation y = 0.2321x – 0.0634 and R2 = 0.9998 which
indicates chemisorption.
