ASTM D1157 Standard Test Method for Total Inhibitor Content (TBC) of Light Hydrocarbons
3. Summary of Test Method
3.1 The catechol is separated from the butadiene by evaporation. The residue is dissolved in water and an excess of ferric chloride is added. The intensity of the yellow-colored complex is compared in a photoelectric colorimeter with that produced by known concentrations of the catechol.
4. Significance and Use
4.1 p-tertiary-butylcatechol is commonly added to commercial butadiene in amounts of 50 to 250 mg/kg as an oxidation inhibitor. This test method is suitable for use by both producers and users of butadiene within the limitations described in Section 1.
