ASTM D5808 Organic Chloride in Aromatic Hydrocarbons and Related Chemicals
ASTM D5808 Standard Test Method for Determining Organic Chloride in Aromatic Hydrocarbons and Related Chemicals by Microcoulometry
9. Hazards
9.1 Consult the current version OSHA regulations, supplier's Material Safety Data Sheets, and local regulations for all materials used in this test method.
10. Sampling
10.1 Consult guidelines for taking samples from bulk in accordance with Practice D3437.
11. Preparation of Apparatus
11.1 Install the instrument in accordance with manufacturer's instructions.
11.2 Adjust gas flows and pyrolysis temperature(s) to the operating conditions as recommended by the manufacturer.
11.3 The actual operation of injecting a sample will vary depending upon the instrument manufacturer and the type of inlet system used.
11.4 Prebake the sample boats to be used for the determination.
12. Calibration and Standardization
12.1 Using the chloride standard stock solution (see 8.21), make a series of three calibration standards covering the range of expected chloride concentration.
12.2 Into three 100-mL volumetric flasks, respectively pipet 1, 15, and 30 mL of chloride stock solution and dilute to the mark with solvent. (The standards are approximately 1 mg Cl/mL, 15 mg Cl/mL H and 30 mg Cl/mL.)
12.3 It is customary to use a one-point calibration, but if analyzing a wide range of samples, use a three-point calibration.
12.4 The sample size can be determined either volumetrically, by syringe, or by mass. Make sure that the sample size is 80 % or less of the syringe capacity.
12.4.1 Volumetric measurement can be utilized by filling the syringe with standard, carefully eliminating all bubbles, and pushing the plunger to a calibrated mark on the syringe, and recording the volume of liquid in the syringe. After injecting the standard, read the volume remaining in the syringe. The difference between the two volume readings is the volume of standard injected. This test method requires the known or measured density, to the third decimal place. Several densities of various hydrocarbons are listed in Table 1.
12.4.2 Alternatively, the syringe may be weighed before and after the injection to determine the weight of sample injected. This technique provides greater precision than the volume delivery method, provided a balance with a precision of ± 0.0001 g is used.
12.5 Follow the instrument manufacturer's recommendation for introducing samples into the instrument.
12.6 Repeat the measurement of each calibration standard at least three times.
12.7 If the calibration standards come out high or low, prepare fresh standards. If the calibration standards remain high or low, follow the instrument manufacturer's recommendations to correct.
12.8 Construct a three-point curve using the instrument manufacturer's recommendations.
