Ion pair formation with ionic liquids for highly efficient microextraction of arsenic

ALEXANDER CASTRO GRIJALBA; LETICIA B. ESCUDERO; RODOLFO G. WUILLOUD

Buenos Aires

Congreso; 5º CONGRESO INTERNACIONAL SOBRE EL ARSÉNICO EN EL MEDIO AMBIENTE; 2014

International Society of Groundwater for Sustainable Development

Several phosphonium-ionic liquids (ILs) were studied to assay their application as ion-pairing agents. Basically, a selective microextraction procedure is proposed based on the formation of As(V)-molibdate complex followed by ion pair reaction with ILs. The ion pair was extracted into a few L of solvent and As was determined by direct injection in electrothermal atomic absorption spectrometry (ETAAS). A 100% recovery was obtained with several ILs and a preconcentration factor of 62.5 has been achieved. The detection limit was 0.001 μg/ L. The use of organic solvents was significantly diminished, turning this analytical method into an environmentally-friendly alternative fitting the concept of green chemistry.