title: [Enrichment of trace iron with activated carbon in Bi-based superconductor powder and determination by inductively coupled plasma atomic emission spectroscopy].
abstract: A new method for determination of trace iron in superconductor powder by ICP-AES was proposed. The instrument parameters were optimized, and the matrix effects as well as the method of eliminating interferences were also studied systemically. The results showed that matrix interference was serious when the amount of matrix increased, and the repeatability was poor, so it was necessary that separation and preconcentration were used to improve the accuracy and precision. In the experiment, complex was formed with Fe and phenanthroline after the matrix elements Bi and Cu were masked by triethanolamine in an appropriate acidity condition. Then the complex was quantitatively adsorbed by activated carbon, and desorbed by 1 : 1 HNO3. The enrichment conditions were investigated in detail. Under the optimal condition, an artificial sample was analysed, and the result was identical with reference values, with the RSD and detection limit being 2.42% and 0.033 microg x g(-1), respectively. The method was applied for the determination of trace iron in Bi-based superconductor powder samples with satisfactory results, in which the recoveries experiment was performed with the recovery coefficient falling in the range of 95.6% to 98.0%.
authors.affiliation: Department of Chemistry, University of Science and Technology Beijing, Beijing 100083, China. huangustb@126.com
authors.forename: Wen-jie
authors.initials: WJ
authors.lastname: Huang
authors.forename: Jian-qiang
authors.initials: JQ
authors.lastname: Li
authors.forename: Hui-li
authors.initials: HL
authors.lastname: Fan
authors.forename: Li-xin
authors.initials: LX
authors.lastname: Fan
authors.forename: Rui
authors.initials: R
authors.lastname: Bao
authors.forename: Xia
authors.initials: X
authors.lastname: Zhang
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Qing
authors.initials: Q
authors.lastname: Lu