Katchalsky—Spitnik

Huizenga (1977) investigated the acid—base properties of twelve marine DOM samples and one combined river water sample and used the Katchalsky— Spitnik model (eq. 2) to numerically estimate pKa, m and total number of Type 1 sites (—COOH groups), in the range pH 3—8. Although the overall... 

Equation (16) is a modified Henderson-Hasselbaleh equation and is usually attributed to Katchalsky and Spitnik (1947). Some of the authors who have applied this equation to humic substances include Pommer and Breger (1960), Huizenga and Kester (1979), Dempsey and O Melia (1983), and Varney et al. (1983). While experimental data for humic substances are fitted reasonably well by this equation, the fundamental assumption that all carboxyl groups are inherently identical in the absence of formally charged groups must not be overlooked. 

Katchalsky A, Spitnik P. Potentiometric titrations of polymethacrylic acid. J Polym Sci 1947 2 432-446. 

Katchalsky A, Mazur J, Spitnik P. General behavior of biocolloids and polyelectrolytes in solution (continued) polybase properties of polyvinylamine. J Polym Sci 1957 23 513-532. 

Titrations of 0.0 lAf poly ampholyte in the presence of O.OIM nitric acid and ITif potassium nitrate were carried out vdth O.IAA potassium hydroxide solution. The dissociation constants were determined on the basis of the Henderson-Hasselbalch equation, as modified by Katchalsky and Spitnik [20], by measuring the pH as a function of the degree of neutralization a... 

Katchalsky, A. and Spitnik, P. Interactions entre poly61ectrolytes, Colloques Internationaux du Centre National de la Recherche Scientifique, No. LVII, Quelques aspects generaux de la science des macromolecules Strasbourg, Editions du Centre National de la Recherche Scientifique, Paris 1955, p. 103. 

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