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Abstract

Based on a recent theoretical study [1] in this work, the potential of applying non linear gradients in preparative chromatography was evaluated. The second eluting component of a ternary mixture was considered as the target component. Systematic experiments were conducted for a model systems using reversed phase chromatography. The target component was provided a) in excess or b) in low amount. Concave and convex gradients were analysed and compared with the conventional linear gradient. A main result of the study is the fact that a significant improvement in productivity can be achieved if the gradient shapes are carefully designed. This requires extended preliminary experimental investigations in order to quantify the effect of the mobile phase composition on the specific distribution equilibria. Another result is the demonstration that the Crag model is capable to quantify the essential features of the gradient elution. 1. Y. Shan, A. Seidel-Morgenstern, J. Chromatogr. A 1093, 47-58