INTERLAMELLAR ADSORPTION OF 1-PENTANOL FROM AQUEOUS-SOLUTION ON HYDROPHOBIC CLAY MINERAL

The adsorption and desorption of aqueous l-pentanol solutions on hydro phobized layer silicates (octadecylammonium vermiculite) were studied by determining adsorption isotherms on the one hand, and enthalpy isot herms obtained by the microcalorimetry method on the other, The adsorp tion displacement process was analyzed by X-ray diffraction and values of basal spacing (d(L)) were determined. By combining these three met hods, calculations of the composition and structure of the interlamell ar space were carried out. Data obtained by microcalorimetry proved: ( i) that the interlamellar adsorption of n-pentanol is an endothermic p rocess: and (ii) that adsorption-desorption in the region of the alkyl chains of the adsorbed surfactant molecules is kinetically inhibited.