The composite adsorbent (chitosan-coated acid treated
coconut shell carbon) exhibited effectiveness in the removal
of Zn from aqueous solution. The removal efficiency was controlled
by solution pH, adsorbent concentration and agitation
times, initial ion concentration and particle size. Adsorption data
fitted well with the Langmuir and Freundlich models. However,
Langmuir isotherm displayed a better fitting model than Freundlich
isotherm because of the higher correlation coefficient
that the former exhibited, thus, indicating to the applicability
of monolayer coverage of the Zn (II) on the surface of adsorbent.
Using coconut shells and aquatic waste such as chitin to
produce activated carbons potentially provide a less expensive
raw material, a highly effective adsorbent as well as producing
activated carbon processed from renewable resources instead of
non-renewable ones.