Simultaneous spectrofluorimetric determination of cerium(III) and cerium(IV) by flow injection analysis

Cerium(III) (1–100 μg l^?1) is determined by injection into a carrier stream of hydrochloric, perchloric or sulphuric acid, and monitoring its native fluorescence. Cerium(IV) can be determined similarly by incorporating a zinc reductor minicolumn into the system. Splitting the injection sample so that only part passes through the reductor, and the remainder by-passes it, allows total cerium and cerium(III) to be detected from the two sequential fluorescence peaks obtained.