| Summary: | Improvement of degree of active sites deprotection as effort to enhance the adsorption capacity of crosslinked humic acid (HA)-chitosan has been carried out. The previously result (Santoso et al, 2008) showed that protection of active sites of HA before crosslinking reaction enhanced the adsorption capacity of the sorbent significantly, although about 50% of protector is still remained on the sorbent. The improvement effort was performed by using variation of the kind of leaching reagent (EDTA, HCl, and HNO3), concentration of reagent, and reaction time. The result showed that the ability of EDTA to deprotection of active sites from the sorbent was higher than either HCl or HNO3. Optimum concentration of EDTA and reaction time were 0.05 M and 24 h, respectively. For the degrees of active sites deprotection are 47.3%, 75.7%, and 98.7%, the adsorption capacity of the sorbent toward Pb(II) are 416.6, 976.9, and 1008.8 mg/g, respectively.
|
|---|