title: Extraction with long-chain amines-IV Separation and colorimetric determination of gold.
abstract: A highly selective method, almost free from interferences, for extraction of gold(III) from sulphuric acid into a chloroform solution of trioctylamine (TOA) is described. The yellow extract is then measured at 325-330 nm. Gold can be determined in the presence of platinum. The method has been applied to the determination of gold in waste dumps. A more sensitive method is based on reaction of the gold with diphenylcarbazide after the separation of the gold from the TOA-chloroform extract. The violet colour is stable and is measured at 560 nm.
authors.affiliation: Analytical Laboratory, Institute of Geological Sciences, Charles University, Prague 2, Albertov 6, Czechoslovakia.
authors.forename: J
authors.initials: J
authors.lastname: Adam
authors.forename: R
authors.initials: R
authors.lastname: Pribil