Determination of Thorium and its Separation from Rare Earths in Monazite Sand

Abstract

AbstractA new method based on precipitation from homogeneous solution and devised for the separation and determination of thorium in monazite sand, consists of four step3: decomposition of monazite sand with sulfuric acid, removal of phosphate radical by washing with alcohol, precipitation of thorium, rare earths and some other constituents in monazite sand with ammonium carbonate in the presence of tartaric acid, and separation of thorium from the rare earths by the hydrolysis of urea in the presence of formic acid. The separation of thorium from a small amount of other constituents associated with the basic thorium formate, is easily carried out by oxalic acid method at the last operation. Approximately ninety‐five per‐cent of phosphate radical can be removed with alcohol. After the removal of phosphate radical, the determination of thorium and its separation from the rare earths is very much simplified. The formation of dense, easily filtered and washed precipitates result in a more accurate and rapid method.