On the Informativity of Higher-Order Moments in Chromatography

Analytical solutions have been obtained for ordinary, normalized, and higher-order (third- and fourth-order) central moments using the model of an equilibrium adsorption layer. The solutions are represented by one-term fractions and comprise the length of an adsorbent layer, the velocity of a mobile phase, the effective kinetic constant, and the Henry constant. Expressions for the third- and fourth-order moments have been obtained and analyzed in the case of the rectangular input signal . It has been shown that, when solving the inverse problem of chromatography, the calculation of the higher-order moments provides no new information on the kinetic or any other properties of an adsorbent layer.