Direct spectrophotometric determination of Nd and Er in mixed rare earths with 8-hydroxyquinoline-5-sulphonic acid and cetylpyridinium chloride

Talanta. 1990 Mar;37(3):337-40. doi: 10.1016/0039-9140(90)80063-l.

Abstract

Neodymium and erbium can form stable ternary complexes with 8-hydroxyquinoline-5-sulphonic acid and cetylpyridinium chloride, but a photometric method based on this does not give high enough sensitivity and is subject to interference by cerium. Use of the third derivative spectra, however, eliminates the interference by cerium and increases the sensitivity.