Direct determination of chlorophenols in environmental water samples by hollow fiber supported ionic liquid membrane extraction coupled with high-performance liquid chromatography

Abstract

The 1-octyl-3-methylimidazolium hexafluorophosphate ([C 8 MIM][PF 6 ]) ionic liquid was immobilized in the pores of a polypropylene hollow fiber for hollow fiber-protected liquid-phase microextraction. Analytes including 4-chlorophenol (4-CP), 3-chorophenol (3-CP), 2,4-dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP) were extracted into this ionic liquid membrane, and back extracted into 10 L sodium hydroxide acceptor solution in the lumen of the hollow fiber. Then, the acceptor solution was withdrawn into the high-performance liquid chromatography (HPLC) microsyringe connected to the hollow fiber, and directly injected into the HPLC system for analysis. Some parameters that might affect the extraction efficiency were optimized, and low detection limits (0.5 g L −1 for 4-CP, 3-CP, DCP and 1.0 g L −1 for TCP) were obtained. Good repeatability was achieved because of the stability of the hollow fiber-supported ionic liquid membrane. The proposed procedure was applied for direct determination of the four chlorophenols in some real water samples including groundwater, river water, wastewater and tap water. All of the four chlorophenols in these water samples were under the limits of determination, and the recoveries were in the range of 70.0-95.7% at 5 g L −1 spiked level.

Bacterial communities of Beijing surface waters as revealed by 454 pyrosequencing of the 16S rRNA gene

“…Furthermore, the abundance of Actinobacteria may be affected by the abundance of humic substances in water samples. It has been reported that humic acid concentrations range from 0 to 50 mg/L in most environmental surface waters (Peng et al 2007). Actinobacteria may be related to the consumption of humic substances, which plays a Fig.…”

Ionic Liquids in Separation Techniques

“…Using 1-hexyl-3-methylimidazolium tetrafluoroborate in temperature-controlled dispersive liquid-phase microextraction pyrethroid pesticides (Zhou et al, 2008) were isolated from aqueous solution. Headspace liquid-phase microextraction using 1-octyl-3-methylimidazolium hexafluorophosphate was applied for extraction of halomethanes, alkyl aromatic compounds (Aguilera-Herrador et al 2008a,b, 2009, and chlorophenols (Peng et al, 2007). 1-Butyl-3-methylimidazolium hexafluorophosphate enabled the separation of chlorobenzenes and chloroanilines (Vidal et al, 2007).…”

Sorption of chlorophenols on microporous minerals: mechanism and influence of metal cations, solution pH, and humic acid

“…The current drinking water guideline values in the US for 2-CP and 2,4-DCP are 0.1 and 0.5 μg/L, respectively (Pera-Titus et al 2004). The EU has set target limits in drinking water of 0.5 and 0.1 μg/L for total content of chlorophenols and individual ones, respectively (Peng et al 2007;Elci et al 2011).…”