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7702226 
Journal Article 
SYNERGISTIC EXTRACTION OF CADMIUM AND COBALT WITH MIXTURES OF 4-STEAROYL-PYRAZOL-5-OL AND TRI-NORMAL-OCTYLAMINE IN TOLUENE 
SIGIT; Goetzgrandmont, GJ; Brunette, JP; , 
1992 
1 
Monatshefte für Chemie / Chemical Monthly
ISSN: 0026-9247
EISSN: 1434-4475 
SPRINGER-VERLAG WIEN 
VIENNA 
373-381 
WOS:A1992HT33000003 
The synergistic extraction of cobalt and cadmium (M2+) from 1 M sodium perchlorate medium with mixtures of 1-phenyl-3-methyl-4-stearoyl-pyrazol-5-ol (HPMSP) and tri-n-octylammonium perchlorate (TOAH+, ClO4-) in toluene, at 25-degrees-C, has been studied. Co and Cd are extracted as M(PMSP)2 species with HPMSP alone (log12 = -7.4 and -9.4, respectively), and as [TOAH+, M(PMSP)3-] species in the presence of (TOAH+, ClO4-). At high (TOAH+, ClO4-) concentrations, the synergistic equilibrium is: M2+ + 3 HPMSP + 1/2(TOAH+, ClO4-)2 half arrow right over half arrow left [TOAH+, M(PMSP)3-] + 3 H+ + ClO4 of constant log K131 = -7.10 and -9.45 (M = Co and Cd, respectively). Owing to the anionic exchange between HPMSP and (TOAH+, ClO4-) (log K(exc) = -4.0) that occurs at highest pH range, the synergistic extraction of cadmium, at low ammonium concentrations, is better described by: Cd2+ + 2 HPMSP + (TOAH+, PMSP-) half arrow right over half arrow left [TOAH+, Cd(PMSP)3-] + 2 H+ of constant log K121 = -4.65.