ASTM D4291 standard test method for trace ethylene glycol in used engine oil
5. Apparatus
5.1 Gas Chromatograph - Any gas chromatograph
equipped with the following:
5.1.1 Flame Ionization Detector, capable of operating continuously at a temperature equivalent to the maximum column temperature employed, and connected to the column so as to avoid any cold spots.
5.1.2 Sample Inlet System, providing for on-column injection and capable of operating continuously at a temperature equivalent to the maximum column temperature employed.
5.2 Recorder - Recording potentiometer with a full-scale response time of 2 s or less may be used.
5.3 Column - 1.2-m (4-ft) by 6.4-mm (1/4-in.) copper tube packed with 5 mass % Carbowax 20-M liquid phase on 30/60 mesh Chromosorb T solid support.
5.4 Integrator - Manual, mechanical, or electronic integration is required to determine the peak area. However, best precision and automated operation can be achieved with electronic integration.
5.5 Centrifuge - RCF 600 minimum and centrifuge tubes with stoppers.
5.6 Syringe - A microsyringe, 10 µL is needed for sample introduction.
5.7 Pasteur Pipets.
5.8 Vials, 2 mL, with crimped septum caps.
6. Reagents and Materials
6.1 Purity of Reagents - Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all reagents 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 - Unless otherwise indicated, references to water shall be understood to mean reagent water as defined by Type II of Specification D1193.
6.3 Air and Hydrogen - Warning: Precaution - See Note 2. (Warning - See Note 3.)
NOTE 2 - Precaution: The air supply may be from a cylinder under high pressure.
NOTE 3 - Warning: Hydrogen is an extremely flammable gas under pressure.
6.4 Calibration Mixtures - A minimum of three mixtures of water and ethylene glycol are prepared to cover the range from 5 to 200 mass ppm. Prepare one blend of approximately 2000 mass ppm ethylene glycol in water to provide for accurate weighing; then, prepare dilutions of that solution.
6.5 Carrier Gas, helium or nitrogen may be used with the flame ionization detector. (Warning: Precaution - See Note 4.)
NOTE 4 - Precaution: Helium and nitrogen are compressed gases under high pressure.
6.6 Ethylene Glycol, 99 mass % pure.
6.7 n-Hexane, 99 mol % pure. (Warning: Precaution - See Note 5.)
NOTE 5 - Precaution: n-Hexane is extremely flammable, harmful if inhaled, may produce nerve cell damage; see A1.1.
6.8 Liquid Phase and Solid Support, 5 mass % Carbowax 20-M liquid phase on 30/60 mesh Chromosorb T solid support.
6.9 Tubing, 6.4 mm (1/4 in.) in outside diameter, 1.2 m (4 ft) long of copper.
6.10 Water, deionized or distilled.
