title: [Simultaneous determination of 1-sulfo-cyclohexane carboxylic acid and sulfate anion in the by-products of caprolactam by high performance liquid chromatography-indirect photometric analysis].
abstract: An improved anion-exchange chromatographic method was developed for simultaneous quantification of 1-sulfo-cyclohexane carboxylic acid (SCCA) and sulfate anion in the by-products of caprolactam. An strong anion chromatographic column and an ultraviolet (UV) detector were chosen for the assay of SCCA and sulfate anion. Non-chromophore-containing sulfate anion is not directly adaptable to the commonly used ultraviolet detection of high performance liquid chromatography (HPLC). This paper reports the development and validation of an HPLC assay for SCCA and sulfate anion based on indirect ultraviolet detection. An ultraviolet-absorbing reagent (the probe), phthalic acid (PA), was added to the mobile phase to induce a signal for the compound. The proposed method was qualified based on the performance criteria of repeatability, intermediate precision and linearity. The limits of detection were 1.0 g/L for both the analytes. The linear ranges varied from 0.50 to 40.0 g/L for SCCA and from 0.10 to 10.0 g/L for sulfate anion, with the correlation coefficients of 0. 999 97 and 0.999 14, and the recoveries of 93.33%-97.40% and 98.50%-101.00%, respectively. The established method can be used in practice to determine SCCA and sulfate anion simultaneously with perfect separation selectivity.
authors.affiliation: State Key Laboratory of Green Catalysis and Reaction Engineering , College of Chemical Engineering, Xiangtan University, Xiangtan 411105, China.
authors.forename: Zhixiang
authors.initials: Z
authors.lastname: Yan
authors.forename: Zhengkang
authors.initials: Z
authors.lastname: Duan
authors.forename: Linan
authors.initials: L
authors.lastname: Li
authors.forename: Haitao
authors.initials: H
authors.lastname: Li
authors.forename: Qiuyun
authors.initials: Q
authors.lastname: Chen
authors.forename: Ye
authors.initials: Y
authors.lastname: Peng