Spectrophotometric Determination of Cerium (III) with Methyl Xylenol Blue and Cetylpyridinium Chloride

Methyl xylenol blue forms a blue complex with cerium(III) in the presence of cetylpyridinium chloride at pH 7.6-9.5, and 0.5-3.5 μg of cerium(III) can be determined from the absorption of this blue complex at 645 mμ. Methyl xylenol blue can also be utilized for direct chelate titration of cerium(III) in the region of hexamine in the same way as methyl thymo1 blue and xylenol orange. In both cases, methyl xylenol blue coloration is comparatively easily affected by coexisting ions.