Ion Chromatographic Determination of Sulfur Oxides in the Atmosphere by Lead Peroxide Candle Method

Abstract

An improved method was demonstrated for measuring sulfur oxides in the atmosphere with the lead peroxide candle. An ultrasonic bath was used for extracting the lead sulfate formed in the candle instead of water bath ordinally used. The recovery of sulfate ion was 95-101% with 2.4% (n=6) relative standard deviation by extracting with 4% sodium carbonate solution at 50°C for 10 min or more. An ion chromatograph (IC) was used to determine sulfate ion with high-sensitivity instead of conventional gravimetric or colourimetric determination. A good agreement was obtained between the sulfur oxides concentration determined by the IC and that by gravimetric analysis. The proposed IC method is sensitive and easy to determine sulfur oxides in the atmosphere with saving time and labor, and can be used as a short-term monitoring (for example a week or so) of sulfur oxides.