| Summary: | Immobilization of humic acid on chitosan using protected cross-linking
method and its application as adsorbent of Cd(II) and Hg(II) ion has been done.
This research was initiated with isolation of humic acid and chitin deacetylation.
Immobilization was done by interacting humic acid with Cd(II) ion before crosslinking
on chitosan using glutaraldehyde as cross-linking agent. After crosslinking,
Cd(II) ion is deprotected using EDTA solution. Resulted adsorbent is
characterized using infrared spectrophotometer and used to adsorp Cd(II) ion by
analyzing effect of pH, rate and adsorption equilibrium constant, identification of
functional group that plays its role in adsorption, and effect of other ion metal
specially Hg(II) toward adsorption.
The isolated humic acid has ash content of 0.73% and chitosan has
deacetylation degree of 74.21% for base line (a) method and 82.88% for base line
(b) method. The result showed that adsorption of Cd(II) ion by adsorbent is
optimum at pH 6. The adsorption of Cd(II) ion by the adsorbent follows the
pseudo second order kinetic model of Ho with adsorption rate constant of 0.2034
g/mg minute. Functional groups contained in adsorbent that plays its role in
adsorption of Cd(II) ion are �COOH and �OH group. Forming Cd(II) ion template
at humic acid active site protection is not effective to enhance selectivity of
resulted adsorbent toward Cd(II) ion at the presence of Hg(II) ion.
Keywords: humic acid, chitosan, immobilization, cross-linking, adsorption
|
|---|