Determination of platinum emissions from a three-way catalyst-equipped gasoline engine

Platinum emissions from two automotive monolithic catalysts have been determined under laboratory conditionson a computer controlled dynamometer. Three stationaryspeed simulations and the U.S.-75 cycle were applied. Particles were classified on a Berner impactor and analysed by atomic absorption spectrometry using a signaladdition technique. Condensates were also sampled to determine volatile compounds. For quality control, several matrix element studies were performed to demonstrate the accuracy of the analytical method. The emissionconcentrations, as determined in several test runs andrepetitive sampling, range from 3 to 40 ng-3. In contrast to published data from pellet oxidation catalysts,the emission concentrations determined are lower by 2 orders of magnitude. A possible volatile or watersoluble platinum fraction is most probably negligible.