Computer-aided method for studying the extraction behaviour and determining the extraction constants of ion pairs. Pt. 1

Extraction behaviour of several tetra-n-alkylammonium picrate ion pairs was studied. Experimental curves were compared with theoretical curves, which were obtained by computer calculation of concentration of the ion pair in the organic phase as a function of the initial aqueous concentration of both ion-pairing agents, the extraction constant, the phase volume ratio and, when appropriate, the dissociation constant of the ion-pair in the organic phase. The extractions were performed both in batch and in a laboratory-made-flow extraction unit. Log Kex values between 0 and 7 and pKdis=-log Kdis values between 4 and 5 were determined. (author). 15 refs.; 8 figs.; 5 tabs