Abstract: A process for the recovery of magnesium from sea water, brine or impure magnesium salt solutions using an extraction technique with solvents to obtain a concentrate and pure magnesium salt solution or a high purity crystallized magnesium salt. The process consists of two basic stages, high selectivity magnesium extraction and re-extraction with an organic phase as an intermediate vehicle.

Abstract: The present invention relates to a process for eliminating mercury from industrial waste waters by means of extraction with solvents, which includes its treatment with an oxidant agent to pass the whole of the mercury to its state of valence Hg.sup.++, its subsequent treatment by direct contact with a reducer in order to eliminate the excess oxidant which otherwise would degrade the agent of extraction and with an organic solution that contains the agent that extracts the mercury and leaves it free from the latter for its evacuation into the environment, and regeneration of the agent of extraction by means of its treatment with an aqueous solution of chloride ions, the mercury being recovered in the form of an aqueous solution of mercuric chloride, relatively concentrated.