ABSTRACT
This chapter takes into account and applies what has been developed in the preceding one. Only, the case of only one simple extraction is considered. The method is also called “batch extraction”. The initial phase (to be extracted) is a solution containing the substance S present in Solvent A. The process is the extraction of S by Solvent B in principle fully immiscible with A. After an energic stirring period and after a period of decantation, one obtains a phase A poorer in S than before, a phase B enriched with S. The whole of both operations (stirring and separation) is called one theoretical stage. Two cases are investigated, those for which the distribution is regular and the other irregular. The regular distribution corresponds to the case where the distribution ratio (ratio of concentrations of S in both solvents) is constant. A simple mathematical (algebraic) study can then be carried out and the concentrations of S in the two phases at the end of the process known. When the distribution is irregular, the solution is geometric. In both cases, the optimum operatory conditions can be inferred from these calculations.
