Abstract
The adsorption of hexachlorocyclohexane (HCH) by modified meerschaum was studied. The comparison of the meerschaum
modified by anion and cation surfactant was conducted to explore their effect on HCH adsorption. The results showed that the
absorbability of HCH by the CTMAB-M (cetyltrimethylammonium bromide-modified) is better than that of SAS-M (sodium
dodecyl sulphonate-modified) because the CTMAB-M has fluffier fibers structure. The addition of amount of adsorbents should
improve the adsorption. When pH value exceeds 11.0, adsorption exhibits optimal behaviour. Results of isotherms studies reveal
that the Freundlich isotherm is the best model in current experimental conditions to describe the adsorption behaviour. The
adsorption kinetics of NM (natural meerschaum) and CTMAB-M followed the pseudo-first-order kinetic model while SAS-M
followed the pseudo-second-order kinetic model. The calculated thermodynamic parameters indicated that the adsorption of
CTMAB-M was spontaneous and endothermal in nature.