Process for the extraction of heavy metals from diluted aqueous heavy metal salt solutions

Abstract

A process for the extraction of heavy metal ions capable of forming complexes with amines from dilute aqueous heavy metal salt solutions consisting essentially of the steps of A. dissolving from 2% to 15% by weight, based on the weight of the dilute aqueous heavy metal salt solution, of at least one vicinal aminoalkanol of the formula ##STR1## wherein R.sub.1 and R.sub.2 are unbranched alkyl having from 1 to 17 carbon atoms and the sum of the carbon atoms in R.sub.1 + R.sub.2 is from 7 to 18, A is a member selected from the group consisting of alkylene having from 2 to 6 carbon atoms and methylalkylene having from 3 to 7 carbon atoms, and y is an integer from 1 to 2, with the proviso that the vicinal substituents are distributed statistically, in a dilute aqueous heavy metal salt solution in the absence of organic solvents, at a temperature below the turbidity temperature of said vicinal aminoalkanols; B. heating the solution to a temperature of at least 10.degree. C above said turbidity temperature whereby two liquid phases are formed, and C. separating the organic phase containing the heavy metal ion.

Dependencies are inferred from the claim text.