ISO/NP 25845

Petroleum products — Determination of organic halogen content

Scope

The method is directly applicable to the determination of low concentrations (2 mg/kg to 100 mg/kg) of organic halogen in petroleum products such as gasolines, middle distillates, marine fuels and residual fuels. The method can also be applied to crude oils; however, no precision data have been established for this additional product type.

Except for fluorine (F), the organic halogens chlorine (Cl), bromine (Br), and iodine (I) that may be present in the sample are determined quantitatively. The halogen is reported as the equivalent number of chloride ions. A sample preparation is described for the removal of inorganic halides from residual fuels before the determination of the organic halogen content. This procedure is essential to obtain a result of organic halogen only.
The methodology used is based on oxidative coulometry or ion chromatography.