Application of chelation ion chromatography to the determination of lanthanides in agriculture.

摘要

Chelation ion chromatography was applied to analyse lanthanides (rare earth elements) in a series of agricultural samples (soil, fertilizers, and roots, stems, leaves of paddy rice). This technique can eliminate most alkalis and alkaline earth metals on chelating concentrator column and eliminate transition metals on the cation exchange column from complex matrices with an ammonium acetate buffer, while the lanthanides are concentrated. The method was capable of separating and determining all lanthanides on a mixed-bed ion exchange column in a wide variety of sample types with high accuracy. Elution is carried out with a concentration gradient of oxalic acid and diglycolic acid, coupled with post-column spectrophotometric detection with 4-(2-pyridylazo)resorcinol at 520 nm. It can determined at ng/ml scales of lanthanides. The total run time after sample injection is～55 min.