The direct determination of mercury by atomic-absorption spectrophotometry at 184·9 nm by using a nitrogen-separated nitrous oxide-acetylene flame

Abstract

A modified atomic-absorption spectrophotometer with a nitrogen-purged optical path has been used for the direct determination of mercury by atomic-absorption spectrophotometry, by using a nitrogen-separated pre-mixed nitrous oxide-acetylene flame and electrodeless discharge lamp source. The high transparency of the fuel-rich flame below 200 nm permits the use of the principal resonance line of mercury at 184·9 nm for its determination. The sensitivity (for 1 per cent. absorption) enhancement obtained by using this line rather than the 253·7-nm line is fifty-fold; detection limits for mercury(I) and mercury(II) of 0·02 p.p.m. and 0·05 p.p.m. are achieved in aqueous solution.