1. Scope

1.1 This standard specifies quinoline phosphomolybdate method for the determination of phosphorus content of unused lubricating oil and additive concentrates. The method is applicable to products containing any of the phosphorus compounds in normal use and having phosphorus contents between 0.005 and 10.0 percent (m/m).

NOTE - There is no reason to doubt its applicability to filtered, used lubricating oils, but no systematic study of this application has been made.

1.2 The methods is free from most interferences because the high insolubility of the quinoline phosphomolybdate precipitate leads to constant composition and freedom from most adsorbed or occluded impurities, especially from cations which would otherwise interfere in the subsequent titration of the precipitate.

NOTE - Barium, calcium, magnesium, zinc, iron, aluminium, alkali salts, citric acid and citrates, chromium up to 18 times the phosphorus content and titanium up to 3.5 times do not interfere with the method.

2. REFERENCES

The standards listed below contain provisions which, through reference in text, constitute provisions of this standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below.

1070 : 1992 Reagent grade water (third revision)

1997 : 2008 Laboratory glassware - Burettes (third revision)