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Lab Methods

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Acid Number

  • Method ASTM D974
  • Repeatability None Established
  • Reproducibility None Established
  • Blending linear
  • Additive Correction No

The purpose of this test is to determine the amount of acidic components in distillates such as Jet fuel, Kerosene, Light Diesel, etc. A specified amount of sample is weighted and introduced into the titration solvent (Isopropyl Alcohol/Toluene/Water). An indicator is added to the mixture which will allow the end point of the titration to be seen visually. The color will change from gold to green when the end of the titration is reached.

Most products that contain acidic or basic components were added to the product as a fuel treatment additive. Degrading of the sample can also cause these components to form. It is a good indication of how corrosive the product may be to the engine using it or the storage holding it.