Thermodynamic investigation of surface of minerals

A Simple Experimental Way of Measuring the Hamaker Constant A11 of Divided Solids by Immersion Calorimetry in Apolar Liquids

“…In the case of nonpolar liquids, values of k obtained for several aluminosilicates are about 2.6 ± 0.2 (22,23,30). Combining Eqs.…”

“…The second difficulty lies in the actual thermodynamic sense of γ LW . It has been shown (22,24,30) that, in the model of van Oss-Chaudhury-Good (31)(32)(33), this term characterizes a solid-vapor surface at equilibrium at ambient temperature and pressure. This means that it is a physical state where vapor is adsorbed.…”

“…This is now possible by the recent development of the interpretation of immersion calorimetry (22)(23)(24)(25)(26).…”

“…From the basic equations for this last method and from recent progress (22)(23)(24)(25)(26) in measurement of solid surface energies by calorimetry, we propose in this work to establish a simple relationship between Hamaker constants A 11 of solids interacting in vacuum and the immersion enthalpy determined in a nonpolar liquid. We will compare values obtained using our method with those found in the literature.…”

Effects of Heating and Acid Activation on the Structure and Surface Properties of a Kaolinite-illite-smectite Clayey Mixture

“…The Young equation was used to calculate γ s , the surface tension of the liquid (γ L ) and the solid/liquid contact angle (θ). The surface energy values determined in water were 205.06 ± 2.76 mJ.m -2 for montmorillonite (swelling clay), 151.80 ± 34.98 mJ.m -2 for bentonite [15], and 59.00 mJ.m -2 for kaolinite [16]. The zeta potential as function of pH can also be used to assess the surface properties of clay minerals such as kaolinite [17].…”