# The thoron-tartaric acid systems for the spectrophotometric determination of thorium

January 1, 1994

Thoron is popularly used for the spectrophotometric determination of thorium.  An undesirable feature of its use is the high sensitivity of the reagent toward zirconium. This study describes the use of tartaric acid as a masking reagent for zirconium. Three tartaric acid-thoron systems, developed for the determination of thorium, differ with respect to the concentrations of thoron and tartaric acid. Mesotataric acid, used in one of the systems, is found to be most effective in masking zirconium. The behavior of various rarer elements, usually found associated with thorium ores, is determined in two of the systems, and a dilution method is described for the direct determination of thorium in monazite concentrates.

## Citation Information

Publication Year 1955 The thoron-tartaric acid systems for the spectrophotometric determination of thorium 10.3133/tei571 F. S. Grimaldi, Mary H. Fletcher Report USGS Numbered Series Trace Elements Investigations 571 tei571 USGS Publications Warehouse