This method describes procedures for the determination of free acid, free alkali, and insoluble carbonates in calcium, sodium, and lithium greases, but it is not applicable when the soaps of lead, zinc, aluminium, or other weak bases are present. Erroneous results may also be obtained in the presence of certain additives, for example, sodium nitrite.
Note — The soaps of the weak bases mentioned in 1.1 react with potassium hydroxide, and no method is available whereby the acidity of greases containing them can be directly determined.
IS 1448 Pt.53-1979 history
1979IS 1448 Pt.53-1979 Test methods for petroleum and its products [P: 53] Determination of pH of oils and fats