Simultaneous determination of Fe(II) and Fe(III) in waters by capillary isotachophoresis.
An ITP method for the simultaneous determination of Fe(II) and Fe(III) in waters, based on separation of their EDTA and fluoride complexes, respectively, was developed. The leading electrolyte used consists of chlorides, La(III) as co-counter ion and is buffered with beta-alanine to pH = 3.5. The terminating electrolyte contains caproic acid and L-histidine (pH = 4.5). The method was validated and tested with samples of artificial, ground and treated water with good results, comparable to those obtained by other analytical techniques. Fe(II) and Fe(III) up to 20 mg/L were measured with an RSD = 1.4-1.5% and detection and determination limits of 0.8-0.9 and 3.0-3.5 mg/L, respectively. The ITP method can be recommended for routine utilization in hydroanalytical laboratories.
Praus
P
P
Hydroanalytical Laboratories, Ostrava water and Sewerage Company Inc., Oderská 44, 702 00 Ostrava, Czech Republic.
Blahutová
M
M
D002623:Chemistry Techniques, Analytical; D004492:Edetic Acid / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods*; D005290:Ferric Compounds / Q000032:analysis*; D005296:Ferrous Compounds / Q000032:analysis*; D005459:Fluorides / Q000737:chemistry; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D005290:Ferric Compounds; D005296:Ferrous Compounds; D014874:Water Pollutants, Chemical; D014867:Water; D004492:Edetic Acid; D005459:Fluorides