IP 308: Determination of barium, calcium, magnesium and zinc in unused lubricating oils - Atomic absorption method

Overview:

Scope

This method is intended for the determination of barium, calcium, magnesium and zinc in unused mineral lubricating oils at concentrations within the ranges:

Barium 0,05 to 1,0 %m
Calcium 0,02 to 2,5 %m
Magnesium 0,02 to 0,50 %m
Zinc 0,02 to 0,20 %m

Oils that contain VI improvers may give erroneous results. It is essential that the standards used in this procedure contain the same VI improver, at the same concentration, as that in the dilute oil sample.

The method is limited to unused mineral lubricating oils which are free from aluminium-containing additives.