ISFME extraction of As species from some real water samples using an imidazolium-based task-specific ionic liquid (TSIL): Synthesis and characterization

ABSTRACT

To determine of arsenic species in real water samples using electrothermal atomic absorption spectrometry, a high-performance in-situ solvent formation microextraction technique has been developed using homogenous liquid – liquid microextraction concepts. The developed method was based on the use of a synthesized imidazolium-based ionic liquid (IL) modified with ammonium pyrrolidine dithiocarbamate as a task-specific ionic liquid (TSIL), which was chelated with As(III) and then converted to a hydrophobic IL using ammonium hexafluorophosphate in anion exchange reactions. As(V) was reduced to As(III), using a satisfied reducing agent, and the total amount of As was analyzed using ETAAS. TSIL acts simultaneously as an extracting solvent and a chelating agent. The characterization of the synthesized TSIL was performed using¹³CNMR and FTIR analyses. When optimal conditions were met, linear dynamic ranges of 0.5–50 µg/L and 0.5–20 µg/L were obtained in the determination of As(III) and total As, respectively. The limits of detection (LOD) and quantitation (LOQ) were determined to be 0.021 µg/Land 0.064 µg/L for the determination of As(III) (for concentration 20 µg/L), respectively, and the standard deviation (RSD%, n = 7) was 2.0%. To evaluate the validity of the method, it was successfully applied for As species determination in different real water samples.

KEYWORDS:

• Task-specific ionic liquid
• synthesis and characterization
• arsenic speciation
• solvent-based microextraction
• electrothermal atomic absorption

Disclosure statement

The author(s) declare the following financial interests/personal relationships which may be considered as potential competing interests, Mehdi Hosseini reports financial support was provided by Ayatollah Boroujerdi University (grant number 15664–217320).

Additional information

Funding

The work was financial supported by the Ayatollah Boroujerdi University [grant number 15664-217320]; This research is taken from a research project titled “Determination of some toxic metallic pollutants at trace levels in real samples using liquid-liquid microextraction methods (LLME) and task-specific ionic liquids (TSILs)”.