NUMERICAL SIMULATION OF SURFACE IONISATION AND SPECIFIC ADSORPTION ON A TWO-SITE MODEL OF A CARBON SURFACE

摘要: A two-site (one acidic, one basic) model of the ionisation a carbon-type surface, in presence or absence specifically adsorbing ions, is analysed. The effect various parameters, such as site concentration and strength, ion-adsorption equilibrium constants solution composition, are considered it shown how these parameters influence extent surface adsorption, well charge. Special consideration given to point zero charge (pzc) factors which determine its value. Of particular note finding that when specific adsorption occurs value pzc depends not only on strength itself, but also constant acidic (for cation adsorption) basic anion adsorption). One consequences this dependence that, although tends decrease increase it, equal adsorptions will necessarily cancel out opposing changes. Furthermore, under appropriate circumstances can even though adsorbed more strongly vice versa. graphical proof mass-titration method for determination valid, ions occurs, presented.