The determination of trace amounts of barium in calcium carbonate by atomic-absorption spectrophotometry

Abstract

Barium present at the 1 to 20 p.p.m. level in calcium carbonate is separated from the calcium matrix by co-precipitation on a lead sulphate carrier. The lead sulphate-barium sulphate precipitate is dissolved in an ammoniacal solution of ethylenediaminetetraacetic acid disodium salt and the barium in the resulting solution is determined by atomic-absorption spectrophotometry by using a nitrous oxide-acetylene flame and the atomic line at 553·6 nm.

The method overcomes interferences that occur in the atomic-absorption spectrophotometric determination of barium in the presence of calcium.