Determination of wear metals in aviation lubricating oil by using a simultaneous MPT spectrometer with an automatic reflux extraction system

A novel, simple and economic sample pretreatment system based on reflux extraction was developed for the determination of wear metals in the used aviation lubricating oil by using a simultaneous microwave plasma torch atomic emission spectrometer (MPT-AES). The operating parameters for both sample pretreatment and analysis were studied and optimized. The detection limits are 0.084, 0.043, 0.022, 0.052, 0.064 μg/g for Zn, Cd, Cu, Fe and Pb, respectively. The relative standard deviations are less than 5% (n=5), and the recovery ratios of these elements are in the range of 94.5%-107.4%. The new system was successfully applied to the analysis of the lubricating oil samples.