ASTM D1157 Standard Test Method for Total Inhibitor Content (TBC) of Light Hydrocarbons
5. Apparatus
5.1 Photometer - A sensitive photoelectric photometer capable of producing light of narrow spectral range that is predominantly blue (425 nm).
5.2 Graduates, 100-mL.
5.3 Volumetric Flasks, 100-mL; or stoppered graduated mixing cylinder, 100-mL.
5.4 Erlenmeyer Flasks, 250-mL.
5.5 Funnels, 75-mm diameter.
5.6 Pipet, 5-mL.
6. Reagents
6.1 Purity of Reagents - Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all reagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, where such specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity to permit its use without lessening the accuracy of the determination.
6.2 Purity of Water - References to water shall be understood to mean distilled water.
6.3 Ferric Chloride, Standard Solution - Dissolve 20.0 g of ferric chloride (FeCl3·6H2O) in ethanol (95 %). Add 9.2 mL of HCl (sp gr 1.19), and then dilute with ethanol (95 %) to 1000 mL in a volumetric flask.
6.4 p-Tertiary-Butylcatechol, Standard - (Warning - Potentially hazardous. May cause skin irritation or burns; can be absorbed through the skin. May be harmful or fatal if swallowed. Avoid contact with eyes; may burn and impair vision. May be harmful to respiratory system. May produce quinones and flammable butylenes on decomposition. Use with adequate ventilation. Store in flammable liquids storage area.) Dissolve 0.63 g of p-tertiary-butylcatechol (95 % minimum purity) in 10 mL of ethanol (95 %) and dilute with water to 100 mL in a volumetric flask. When used in place of 100 mL (63 g) of sample, consider 1.00 mL of this solution to be equivalent to 100 ppm of catechol. This solution is not stable and should be prepared as needed.
