EXTRACTION OF ALKALI-METAL PICRATES BY CALIXARENE ESTERS IN THE WATER-NITROBENZENE SOLVENT SYSTEM. THE MEDIUM EFFECT ON PARTITION AND EXTRACTION PROCESSES.

Angela F Danil de Namor (1)

1 Chemistry Division

Based on distribution data involving alkali-metal (Na+, K+, Rb+ and Cs+) picrates in the presence and in the absence of calix[n]arene (n = 4, 6) esters, the extraction ability of these macrocycles in the water-nitrobenzene solvent system is established. Thus, partition and distribution constants in the mutually saturated solvents and ion-pair formation constants in the water saturated organic phase are calculated from distribution data in the absence of these macrocycles. From distribution data in the presence of the ligand, the extraction and the distribution constants are calculated. Within the experimental error, good agreement is found between the distribution constants calculated from distribution data in presence and absence of calixarenes. The individual processes which contribute to the overall extraction of these cations from water to nitrobenzene are discussed. The medium effect on the extraction process is analysed taking into account previously reported data for these systems in water-dichloromethane and water-chloroform.

Mots clés: Physical Sciences

Angela F Danil de Namor. EXTRACTION OF ALKALI-METAL PICRATES BY CALIXARENE ESTERS IN THE WATER-NITROBENZENE SOLVENT SYSTEM. THE MEDIUM EFFECT ON PARTITION AND EXTRACTION PROCESSES.. Supramolecular Chemistry, 2006, 18 (07), pp.575-580. ⟨10.1080/10610270600852289⟩. ⟨hal-00513482⟩