Extraction of arsenic(III) with macroporous resin impregnated with bis(2-ethylhexyl)ammonium bis(2-ethylhexyl)dithiocarbamate

The extraction of arsenic(III) was investigated by using macroporous resin impregnated with a newly synthesized hydrophobic extractant: bis(2-ethylhexyl)ammonium bis(2-ethylhexyl)dithiocarbamate (BBDC). In a preliminary experiment on liquid-liquid extraction, arsenic(III) was favorably extracted with BBDC in heptane from acidic to neutral solutions; the distribution ratios with 0.01 mol dm(-3) BBDC were larger than 10(2.5) at pH 0-6. The batchwise extraction of arsenic(III) with the impregnated resin was carried out. The distribution ratio was more than 10(3) in an acidic region, and sharply decreased above pH 8. The collection of a trace amount of arsenic(III) was performed by using the column packed with the impregnated resin as a stationary phase. Then arsenic(III) retained on the column was quantitatively eluted out with an alkaline solution.