Abstract: The method and apparatus mixes two immiscible liquids A and O to form a dispersion and then pre-separates the dispersion into two fractions (A+o) and (O+a) in a spout. These two fractions are fed separately into a decanter with two separate compartments which continue to maintain the two fractions as separate. Within the two separate compartments the two fractions are further separated into two flows, A, O, a, and o, such that four flows exit the decanter.

Abstract: The invention relates to a process and a solvent for extraction of the chromates present in an aqueous solution. According to the invention, the aqueous phase is brought into contact with an organic phase comprising 2 to 10% by volume of a solvent selected from the group of tertiary or quaternary amines and 15 to 40% of a solvent selected from the group of esters of phosphoric acid in a diluent based on petroleum hydrocarbons. The invention is applicable to the production of concentrated solutions of chromates easily recyclable from an extraction of the chromates contained in an industrial solution.