Volatilization of arsenic(III, V), antimony(III, V), and selenium(IV, VI) from mixtures of hydrogen fluoride and perchloric acid solution: application to silicate analysis

The possible volatilization of As(III, V), Sb(III, V), and Se(IV, VI) from mixtures of HCI04/HF is investigated. It is shown that there are no losses with Sb and Se irrespective of the initial oxidation state, and with As(V). As(III) is partially or totally lost by volatilization; this can be avoided by oxidizing As with HCIO4. The oxidation state of all three elements after the HCIO4/HF treatment Is determined. These results lead to a recommended procedure for the dissolution of siliceous materials in which As, Sb, or Se are to be determined.