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

摘要

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 ofPPA. 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;PPB. HEATING THE SOLUTION TO A TEMPERATURE OF AT LEAST 10 C above said turbidity temperature whereby two liquid phases are formed, andPPC. SEPARATING THE ORGANIC PHASE CONTAINING THE HEAVY METAL ION.