Quantitative ion-exchange separation of submicrogram amounts of iron from phosphate medium

Radiotracer techniques were used to investigate the separation and recovery of submicrogram amounts of iron from major amounts of phosphate resulting from the hydrolysis of phosphorus oxychloride. Iron is retained quantitatively by the column under conditions permitting the efficient elution of phosphate species with 5.OM hydrochloric acid. Iron is then recovered by elution with 0.15M hydrochloric acid-1% hydrazine solution. Precise separations of 10-125 ng of iron with recoveries of 95% or better are reported.