UOP 729

UOP 729 – Phenols in Light Distillates by Direct Titration

This method is for determining phenols and hindered phenols in petroleum fractions up to and including No. 2 distillates; e.g. gasolines naphthas kerosines jet fuels No. 1 fuels and No. 2 fuels. The procedure gives nicely defined titration curves and endpoints on samples up to No. 1 distillate but No. 2 oils sometimes give titration curves with ill-defined endpoints. There is no way to predict this behavior so the analyst must simply try it on the sample.

Phenols as hindered as butylhydroxytoluene (BHT) can be titrated directly using this method. Provision is included to overcome the acidity of mercaptans and thiophenols via a mild oxidation to the corresponding disulfides.