Direct determination of uranium in concentrates by spectrophotometric titration with ferric sulphate.

A direct method is presented for the determination of uranium in uranium concentrates by spectrophotometric titration with ferric sulphate, after a bismuth amalgam reduction. The oxidation of U (IV) by Fe (III) was found to be rapid and complete at room temperature, under suitable conditions. Copper, molybdenum and vanadium interfere to some extent, and their maximum permissible concentrations are discussed. A complete determination may be carried out in little over an hour with a precision of two to three parts per thousand. A "Uvispek" spectrophotometer was adapted for spectrophotometric titrations without modification of the instruments