Simultaneous separation and indirect ultraviolet detection of chlorate and perchlorate by pyridinium ionic liquids in reversed‐phase liquid chromatography

Abstract

A novel approach for the simultaneous separation and indirect ultraviolet detection of chlorate and perchlorate using pyridinium ionic liquids as mobile phase additives in reversed-phase liquid chromatography was developed. Pyridinium ionic liquids and imidazolium ionic liquids as the mobile phase additives were compared. The effects of pyridinium ionic liquids, methanol, column temperature, and detection wavelength on the separation and detection of chlorate and perchlorate were investigated. The role of ionic liquids, retention rules and relevant mechanisms were discussed. Pyridinium ionic liquids mainly acted as ultraviolet absorption reagent and ion-pair reagent. The successful separation and indirect ultraviolet detection of chlorate and perchlorate were achieved by using a common reversed-phase column, 0.2 mmol/L N-octylpyridinium bromide aqueous solution/methanol (90/10, v/v) as mobile phase and at the detection wavelength of 210 nm. The retention times of chlorate and perchlorate were 30.51 and 37.06 min, respectively. The detection limits of chlorate and perchlorate were 0.16 and 0.29 mg/L, respectively. The linearity and repeatability of the method were satisfactory. The approach was used to the analysis of river water samples with accurate and reliable results. This method is easy to popularize due to the use of common reversed-phase column and ultraviolet detector in liquid chromatography.

N-octylpyridine hydrogen sulphate ionic liquid for multifunctional fluorescent response in different solvents

“…Because of these characteristics, ILs are used as alternative electrolytes in lithium-ion batteries and double-layer capacitors [ 12 , 13 ]. ILs are widely used in analytical chemistry applications, such as highly polar capillary columns that can separate complex mixtures in gas chromatography [ 14 ] and mobile-phase additives in liquid chromatography [ 15 ]. ILs have different responses and diverse application performances, characterised using infrared [ 16 ], ultraviolet [ 17 ] and fluorescence [ 18 ] spectroscopies.…”

Trace determination of perchlorate in drinking water by capillary zone electrophoresis with isotachophoresis sample cleanup and conductivity detection

“…The most commonly applied analytical techniques used in the determination of perchlorate are ion chromatography (IC) [18][19][20][21][22][23], HPLC [24,25], CE [26][27][28][29][30][31][32][33][34][35][36][37][38][39] using UV-Vis, MS, and electrochemical detection techniques. US EPA developed many robust analytical methods for the determination of the perchlorate [18], and apart from basic US EPA method 314.0 [19], many new methods emerged with the ability to detect concentrations down to tens of ng/L.…”