PH-METRIC DETERMINATION OF ACID NUMBERS IN PETROLEUM OILS WITHOUT TITRATION

A new pH-metric method without titration has been developed for determ ination of acid numbers lower than 0.1 mg (KOH) g(-1) toil) in petrole um oils such as White, Transformer and Basic oils. The method is based on rapid and complete extraction of acids from an oil test portion in to the novel reagent and measurement of the conditional pH in the 'oil -reagent' mixture by a glass electrode. The method has a quantitation limit equal to 1 x 10(-3) mg (KOH) g(-1) (oil), uses non-toxic reagent s, is not time and labor consuming, and is cheap and simple for automa tion. (C) 1998 Elsevier Science B.V. All rights reserved.