The results of a study of the interfacial kinetics for the extraction of iron(III) in sulfuric acid with /3-alkenyl-8hydroxyquinoline are presented. Use of a liquid jet recycle reactor (LJRR) to obtain the interfacial rate data permits appropriate analysis when mass transfer and interfacial reaction contribute to the overall rate. Ionic speciation in the bulk aqueous phase is modeled to obtain the concentrations of Fe3+ and H+. The postulated mechanism giving rise to the rate expression includes the adsorption of HR and the protonation of HR. It also assumes that the rate-determining step is the formation of FeR2+ in the interfacial region. The postulated model is supported by physicochemical evidence, such as interfacial tension data, and statistical evaluation of the model.

The performance of a continuous-flow stirred tank hydrometallurgical extractor has been simulated. Two models are used for such simulations: a noninteraction model based on macroscopic material balances and an interaction model featuring a stochastic treatment of the microscopic hydrodynamics of the dispersion. The models incorporate equilibrium and intrinsic kinetic expressions pertaining to a chemical system of hydrometallurgical interest: iron(III) sulfate-5-alkenyl-8-hydroxyquinoline/ xylene. Comparison between the model predictions and the experimental results indicates the interaction model to be more accurate than the noninteraction model. However, the computationally simple noninteraction model performance, especially when interdrop Liquid-liquid extraction is an important hydrometallurgical operation. Originally confined mainly to the processing of nuclear fuels, liquid extraction is now increasingly used for obtaining nonnuclear metals of industrial significance. The reasons for increased acceptance of liquid extraction as a commercially viable hydrometallurgical operation are poorer ore grades, stricter pollution control regulations, and higher costs of energy. These factors adversely affect the economy of traditionally practiced pyrometallurgy and favor the energy-efficient, moderately polluting hydrometallurgy.Large-scale hydrometallurgical operations involving liquid-liquid dispersions are usually carried out in mixer-settler contactors. The aim of this work is to study the effect of varying operating conditions on the performance of a continuous-flow stirred tank reactor (CFSTR) commonly employed by the hydrometallurgical industry. To accomplish this objective, a chemical system of iron(III)sulfate-^-alkenyl-8-hydroxyquinoline (/3A8HQ) /xylene was chosen. The incentive for studying the complex iron chemistry arises because of its ubiquitous presence as an impurity in ores of more valuable metals such as nickel and cobalt. The individual investigations on the hydrochemistries of the valuable metal and the undesired impurity are essential prerequisites for the investigation on the selective extraction of the valuable metal from the naturally occurring composite ores. Two reactor models were developed to predict the performance of a CFSTR as a liquid-liquid extractor.These models incorporate the reaction thermodynamics and kinetics of the Fem extraction by /3A8HQ with the dispersion hydrodynamics. The models differ from each other in their treatment of the dispersion hydrodynamics. The total dispersion interfacial area and the interdrop mixing resulting from random drop processes of breakage and coalescence are important factors in the analysis of two-phase liquid-liquid dispersion reactions. The first model (noninteraction model) neglects the interactive droplet processes occurring in a mechanically agitated CFSTR. The interfacial area required to determine the interphase solute transfer is obtained by experimental measurements. The second model (interaction model