Determination of Calcium, Zinc, and Phosphorus in multigrade crankcase oils by XRF, DRES, and ICP‐AES

Abstract

AbstractThe effect of viscosity index improvers such as styrene‐isoprene copolymer (SICP), styrene‐butadiene copolymer (SBCP), ethylene‐propylene copolymer (OCP) and poly(alkyl) methacrylate (PMA), in multigrade oils on the determination of Ca, Zn and P in fresh and used lubricating oils was studied using XRF, DRES and ICP‐AES techniques. Crankcase lubricating oil blends containing known amounts of Ca (2900 ppm), Zn (1700 ppm) and P (1600 ppm) were further formulated with different concentrations of these VI improvers and analysed for their Ca, Zn, and P contents by XRF, DRES and ICP‐AES. Based on a comparison of the resulting analytical data, it was concluded that the VI improvers had no effect on the analysis results, and that the concentrations of Ca, Zn and P in the oil determined by these techniques correlate well with each other.