Adsorption on clay minerals

Figure 2.1. First-order plots of potassium adsorption on clay minerals where Kt is quantity of potassium adsorbed at time f and Kx is quantity of potassium adsorbed at equilibrium. [From Sparks and Jardine (1984), with permission.]...

The publications on amino acid adsorption on clay minerals before 1974 are summarized in the book by Theng (1974). It provides information on the adsorbed quantity of different amino acids on cation-exchange montmorillonites and the characteristic IR bands of amino acid-montmorillonites adsorption compounds. Usually, only the adsorbed quantity of amino acids on montmorillonites is shown, and no adsorption mechanism is usually hypothetized (e.g., Friebele et al. 1981 Rak and Tarasevich 1982), except in Stadler and Schindler (1993a) where the adsorption is evaluated by the surface-complexation model, and the possible surface complexes are given for p-alanine. 

The structure of the organic molecules may also undergo changes as a result of adsorption on clay minerals, causing catalytic transformations (Chapter 1, Section 1.3.5). The cations of the clay minerals may also effect these transformations. 

Bostick, B. C., Vairavamurthy, M. A., Karthikeyan, K. G., and Chorover, J. (2002). Cesium adsorption on clay minerals an EXAFS spectroscopic investigation. Environ. Sci. Technol. 36, 2670-2676. 

Quiquampoix, H., Staunton, S., Baron, M.H. and Ratcliffe, R.G. (1993) Interpretation of the pH dependence of protein adsorption on clay mineral surfaces and its relevance to the understanding of extracellular enzyme activity in soil. 

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