title: Substoichiometric extraction with hexafluoroacetylacetone and tri-n-octylphosphine oxide in cyclohexane Determination of manganese by neutron activation.
abstract: Traces of manganese have been determined quantitatively by neutron activation and substoichiometric extraction with a mixture of hexafluoroacetylacetone and tri-n-octylphosphine oxide in cyclohexane. When applied to calcium carbonate, the specific example cited here, it was necessary to make a prior separation of manganese by extraction with a mixture of pyrrolidinedithiocarbamic acid and diethylammonium dithiocarbamate in chloroform to avoid interferences from calcium. Replicate determination of sub-ppm amounts of manganese in a sample of calcium carbonate showed a relative standard deviation of 6.9% while measurements on a solution prepared by dissolving a refined-silicon standard, SRM 57, indicated a relative error of 6.0%.
authors.affiliation: Bell Laboratories, Murray Hill, New Jersey 07974, U.S.A.
authors.forename: J W
authors.initials: JW
authors.lastname: Mitchell
authors.forename: R
authors.initials: R
authors.lastname: Ganges