Radiochemical Analysis of 35SO2 Adsorbed on Pbo2

Abstract

The concentration of ³⁵SO₂ in air can be measured by reacting with Pbo₂ to form Pb³⁵SO₄. A method was developed which is suitable for rapid, high-protection radioassaying of ³⁵SO₄ ^2- on the surface of Pbo₂. The surface ³⁵SO₄ ^2- was extracted with a quaternary alkylammonium hydroxide in toluene and counted in an organic liquid scintillator solution with an efficiency of approximately 94%, which was constant for 30 days when corrected for natural decay. More than 99.5% of the surface sulfate was extracted in less than 5 minutes for quaternary alkylammonium concentrations 600 times in excess. This technique was shown superior to gas-flow proportional counting of the PbO₂ surface.