The invention relates to a method and apparatus with which an organic solution that is slightly soluble in water is scrubbed of aqueous entrainment and impurities. In particular, the organic solution may be the organic extraction solution of liquid-liquid extraction used in connection with the hydrometallurgical recovery of metals. The purpose is to perform the physical separation of water droplets and the chemical removal of impurities from the organic solution simultaneously. This occurs by routing the solution to be purified in the settling tank through at least one flow plate cassette of reduced cross-section.