title: Online spectrophotometric determination of Fe(II) and Fe(III) by flow injection combined with low pressure ion chromatography.
abstract: A simple and new low pressure ion chromatography combined with flow injection spectrophotometric procedure for determining Fe(II) and Fe(III) was established. It is based on the selective adsorption of low pressure ion chromatography column to Fe(II) and Fe(III), the online reduction reaction of Fe(III) and the reaction of Fe(II) in sodium acetate with phenanthroline, resulting in an intense orange complex with a suitable absorption at 515nm. Various chemical (such as the concentration of colour reagent, eluant and reductive agent) and instrumental parameters (reaction coil length, reductive coil length and wavelength) were studied and were optimized. Under the optimum conditions calibration graph of Fe(II)/Fe(III) was linear in the Fe(II)/Fe(III) range of 0.040-1.0mg/L. The detection limit of Fe(III) and Fe(II) was respectively 3.09 and 1.55μg/L, the relative standard deviation (n=10) of Fe(II) and Fe(III) 1.89% and 1.90% for 0.5mg/L of Fe(II) and Fe(III) respectively. About 2.5 samples in 1h can be analyzed. The interfering effects of various chemical species were studied. The method was successfully applied in the determination of water samples.
authors.affiliation: National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, Sichuan, PR China; College of Food Science, Sichuan Agricultural University, Yaan 625014, Sichuan, PR China.
authors.forename: Shujuan
authors.initials: S
authors.lastname: Chen
authors.affiliation: National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, Sichuan, PR China.
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.affiliation: National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, Sichuan, PR China; State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University, Sichuan University, Chengdu 610065, Sichuan, PR China. Electronic address: zhangxinshen@126.com.
authors.forename: Xinshen
authors.initials: X
authors.lastname: Zhang
authors.affiliation: National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, Sichuan, PR China.
authors.forename: Dongjing
authors.initials: D
authors.lastname: Yang
authors.affiliation: National Engineering Laboratory for Clean Technology of Leather Manufacture, Sichuan University, Chengdu 610065, Sichuan, PR China.
authors.forename: Heimei
authors.initials: H
authors.lastname: Jiang
mesh_terms: D002138:Calibration; D002852:Chromatography, Ion Exchange; D005290:Ferric Compounds / Q000032:analysis*; D005296:Ferrous Compounds / Q000032:analysis*; D017022:Flow Injection Analysis; D007501:Iron / Q000737:chemistry*; D016014:Linear Models; D009862:Online Systems; D010618:Phenanthrolines / Q000737:chemistry; D011312:Pressure; D019163:Reducing Agents / Q000737:chemistry; D015203:Reproducibility of Results; D019346:Sodium Acetate / Q000737:chemistry; D013053:Spectrophotometry; D014867:Water / Q000737:chemistry
chemical_list: D005290:Ferric Compounds; D005296:Ferrous Compounds; D010618:Phenanthrolines; D019163:Reducing Agents; D014867:Water; D019346:Sodium Acetate; D007501:Iron
keywords: Flow injection analysis; Iron; Low pressure ion chromatography; Simultaneous determination