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Determination of lead in gasoline by atomic-absorption spectrophotometry—evaluation of standard methods

Methods for measuring lead in gasoline have been reviewed and a modified procedure evaluated in an inter-laboratory test programme to determine its precision. The test samples are diluted with 4-methylpentan-2-one and the lead alkyls are reacted with iodine and a liquid anion exchanger (Aliquat 336). The lead content of the solution is determined by atomic-absorption spectrophotometry. The method is quantitative and is applied over the range 0.05 to 0.50 g l–1 of lead. It is rapid with good precision and has been adopted as a standard procedure by the Institute of Petroleum.