ASTM D2549 Separation of Representative Aromatics and Nonaromatics Fractions
ASTM D2549 Standard Test Method for Separation of Representative Aromatics and Nonaromatics Fractions of High-Boiling Oils by Elution Chromatography
6. Apparatus
6.1 Chromatographic Columns, as shown in Fig. 1. Different chromatographic columns are provided for the analysis of 2 and 10-g samples.

6.2 Beakers, 100, 250, and 600-mL, inverted-rim type.

6.3 Steam Bath.

6.4 Electric Vibrator, for packing column.

6.5 Weighing Bottles or Erlenmeyer Flasks, 25 and 50 mL.

7. Reagents and Materials
7.1 Purity of Reagents - Reagent grade chemicals shall be used in this test. 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.

7.2 Bauxite, 20 to 60-mesh. Before use, activate the bauxite by heating at 538°C (1000°F) for 16 h. Transfer the activated material to an airtight container while still hot and protect thereafter from atmospheric moisture.

7.3 Chloroform. (Warning - Toxic. May be fatal if swallowed.)

7.4 Cleaning Solution - Chromic-sulfuric acid.(Warning - Causes severe burns. A recognized carcinogen, strong oxidizer, contact with organic material may cause fire.)

7.5 Diethyl Ether, anhydrous. (Warning - Extremely flammable.) The ethyl ether used in this test method should be free of peroxides as determined by the procedure in "Reagent Chemical, American Chemical Society Specifications".

7.6 Ethyl Alcohol, denatured, conforming to Formula 2B of the U.S. Bureau of Internal Revenue. (Warning - Flammable.)

7.7 Pressuring Gas, dry air or nitrogen, delivered to the top of the column at a regulated gage pressure of 0 to 2 psi (13.8 kPa). (Warning - Compressed gas.)

7.8 n-Pentane, commercial grade, aromatic-free. Some samples of waxy stocks may not dissolve completely in n-pentane, in which case cyclohexane, commercial grade, aromatic-free, may be substituted for n-pentane. (Warning - Extremely flammable liquid.)

7.9 Silica Gel, 100 to 200-mesh.