Successive Determination of Picogram Amounts of Phosphorus and Arsenic in Pure Water by Indirect Flameless Atomic Absorption (Mo) Spectroscopy

Abstract

The method involves the conversion of the P and As into the yellow 12-molybdo-phosphate or - arsenate complex, respectively, extraction into butyl acetate (in the case of As - with the preliminary addition of ethanol), the decomposition of the heteropoly-compounds with aqueous NH₃ and the back extraction of the liberated Mo into aqueous solution, for flameless AA determination. 10 pg P and 25 pg As in 0.4 ml samples of ultrapure water were determined with percentage errors below ±30%.

Key Words:

• Trace (picogram) determination of P and As