Analysis of alkyl organoiodide mixtures by high-performance liquid chromatography using electrochemical detection with a post-column photochemical reactor.
A method for the analysis of six alkyl organoiodides (iodomethane, iodoethane, 1-iodopropane, 1-iodobutane, 1-iodopentane, 1-iodohexane) commonly found in acetic acid process was developed. In this method the target analytes were determined by high-performance liquid chromatography (HPLC) using a post-column photochemical reactor with electrochemical detection (ED) in less than 30 min. HPLC was performed in ODS C18 reversed-phase column (5 microm, 250 x 4.6 mm I.D.) under isocratic conditions with methanol-0.067 M acetate buffer (70:30, v/v), pH 6.2 as mobile phase at flow-rate 1.1 ml/min. Alkyl organoiodides, which are electrochemically inactive, were made oxidizable at potential of 120 mV after post-column irradiation with low-pressure mercury lamp in a knitted PTFE tube. The photoreactor was placedin an aluminum housing full of nitrogen in order to prevent from the interference of oxygen. The detection limit for most analytes was of the order of 1-2 microg/l. The HPLC-ED method with a post-column photochemical reactor has good precision and linearity and can be readily applied to the routine determination of alkyl organoiodides in real acetic acid samples.
Wu
Chien-Hou
CH
Department of Atomic Science, National Tsing Hua University, 101, Section 2, Kuang Fu Road, Hsinchu 300, Taiwan.
Lian
Jiunn-Hsiung
JH
Wang
Jia-Lin
JL
Lo
Jiunn-Guang
JG
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004563:Electrochemistry / Q000379:methods*; D010777:Photochemistry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity