ASTM D7041 Standard Test Method for Determination of Total Sulfur in Liquid Hydrocarbons and Hydrocarbon-Oxygenate Blends by Gas Chromatography with Flame Photometric Detection
11. Procedure
11.1 Obtain a test sample using the procedure outlined in Section 8.
11.2 Sample injection volumes can range from 0.1 µL to 1 µL. Experience dictates the best sample volume. The injection volume must be the same as used in the calibration procedure. Typical injection volumes are listed in Table 2.
11.3 Load the sample into the injection valve or auto injector according to the manufacturer's recommended procedure.
11.4 Inject the sample into the chromatograph by starting the chromatographic method, in accordance with the manufacturer's instructions.
11.5 Record concentration reading from gas chromatograph. See Fig. 1 for a typical chromatogram.
11.6 Density values needed for the calculations are to be tested using Test Methods D1298, D4052, or equivalent, at the temperature at which the sample specimen was taken for analysis by this test method.
12. Calculation
12.1 If the analyzer was calibrated on a mass/volume basis then calculate the sulfur content of the test sample in parts per million by mass (mg/kg) as follows:
sulfur, ppm (µg/g, mg/kg) = CSv/DS
where:
CSv = concentration reading from analyzer (µg/mL), and
DS = density of sample (g/mL).
12.1.1 If the analyzer was calibrated on a mass/mass basis then calculate the sulfur content of the test sample in parts per million by mass (mg/kg) as follows:
sulfur, ppm (mg/g, mg/kg) = (CSm)(DC)/DS
where:
CSm = concentration reading from analyzer (mg/kg),
DC = density of calibration standard (g/mL), and
DS = density of sample (g/mL).
