EXTRACTION OF GALLIUM(III) WITH HPMBP

The extraction equilibrium and kinetics of gallium(III) from hydrochlo ric acid solutions with 1 - phenyl - 3 - methyl - 4 - benzoyl - pyrazo lone - 5(HPMBP) in carbon tetrachloride have been investigated. The co mposition of the extracted species was found to be Ga(PMBP)(3) . 2H(2) O via the method of slopes, IR and NMR spectra. The values of K-ex, De lta H degrees, Delta G degrees and Delta s degrees at 298K were calcul ated. The extraction kinetics of Ga(III) was studied with the growing drop method. The extraction rate equation can be expressed as R-f = k( f)[Ga3+][HL]((o)). The activation energy of the reaction was calculate d to be 15. 9kJ . mol(-1). The rate determining step was deduced to ta ke place in water phase:Ga3+ + HL --> GaL2+ + H+,which is an immediate coordination process.