SOLVENT EXTRACTION IN PRESENCE OF EMULSION-FORMING RESIDUES - APPLICATION TO ATOMIC ABSORPTION DETERMINATION OF GOLD IN LOW GRADE ORES

Extraction in the presence of insoluble residues caused a serious emulsion problem in the development of an aqua regia, methyl isobutyl ketone extraction, atomic absorption method for determining microgram quantities of gold in ore samples weighing up to 500 grams. A study of factors affecting the change in volume of ketone during the extraction showed that, under proper conditions, atomic absorption analysis of the small quantity of ketone which separated as a clean phase provided quantitative results. The use of solvent extraction in the presence of insoluble residues which cause the formation of large emulsions has not been previously reported. This technique should have general application in many other extraction methods of analysis. © 1969, American Chemical Society. All rights reserved.