CTAB, adsorption, bituminous coal, montmorillonit

Adsorption of CTAB onto bituminous coal and clay mineral montmorillonite was studied. Values of the CTAB adsorption capacities have been calculated (am = 0.65 mmol/g for coal, 3.24 mmol/g for MMT, respectively). Shape of the adsorption isotherms was correlated with zeta potential values at the adsorption equilibrium. Sorption properties of both sorbents were studied by means of voltammetry on carbon paste electrodes (CPE) modified with coal-CTAB and MMT-CTAB system, respectively. Open circuit sorption with differential pulse voltammetry was performed to compare the sorption properties of the systems with the original sorbents. The Cu2+ sorption on BC and MMT was decreased approximately to 50 % and 40 %, respectively. The surface adsorption mechanism of CTAB on coal due to hydrophilic interactions was suggested. In the case of montmorillonite the CTAB intercalation via ion exchange into the interlayer space forming bi- or trilayer arrangement is supposed.