Application of an Experimental Methodology in the Optimization of a Tungsten Concentration Process by Microemulsions

Abstract

- In this work, we applied an experimental planning methodology in order to correlate the necessary amounts with the description of the a tungsten extraction process by microemulsions. The result is a mathematical modelling carried out using the Sheffe Net method, where the mixtures concentration values are represented inside an equilateral triangle. The tungsten concentration process occurs in two stages: extraction and reextraction. The extraction stage was determined by monitoring: phase relative volume (Vr), extraction percentage (%E) and tungsten concentration in the microemulsion phase (Ct<FONT FACE="Symbol">m</font> e). The reextraction phase was determined by monitoring: reextraction percentage (%Re) and tungsten concentration in the aqueous phase (Ctaq). Finally, we obtained equations that relate the extraction / reextraction properties to the composition of specific points inside the extraction region, obeying the error limits specified for the acceptance of each parameter. The results were evaluated through the construction of isoresponse diagrams and correlation graphics between experimental values and those obtained through use of equations

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