DETERMINATION OF THE ACIDITY OF PETROLEUM BITUMENS BY CATALYTIC THERMOMETRIC TITRIMETRY

The content of acids, including very weak acids, in straight-run and air-blown petroleum bitumens is determined by non-aqueous catalytic thermometric titrimetry. Titration values depend on the nature of the titrant and on the nature and amount of the sample solvent and thermometric indicator. Acrylonitrile is effective in low concentrations and is preferred to acetone as the indicator. With pyridine as the sample solvent, the measured acid contents are similar to those obtained by non-aqueous potentiometric titration. The thermometric method is more convenient. © 1979.