ASTM D5384 Standard Test Methods for Chlorine in Used Petroleum Products (Field Test Kit Method)
8. Procedure (Methods A and B)
NOTE 2 - Perform the test in a dry area with an ambient temperature greater than 15°C (60°F) and adequate light. In cold weather, a truck cab is sufficient.
8.1 Using a volumetric pipette, place 0.40 +/- 0.02 mL of sample into one of the polyethylene tubes.
8.2 Using a volumetric pipette, add 1.5 mL of naphthalene/bis-2-methoxyethyl ether solution. Shake well.
8.3 Add 200 mg of metallic sodium dispersion (80 mg Na) and shake well for 1 min.
8.4 Add 7 mL of aqueous buffer solution to the mixture. Cap and shake well. Vent the tube so that the resulting pressure is released.
8.5 Allow the aqueous and hydrocarbon phases to separate for 2 min. Decant off the aqueous phase and pass 5 mL through the polypropylene filter into a second polyethylene tube.
8.6 Method A (Qualitative at 1000 mg/kg) - Add 0.75 mL of 4.75 mmol/L mercuric nitrate solution to the 5 mL of aqueous filtrate. Shake well.
8.6.1 Add approximately 0.5 mL of diphenylcarbazone indicator solution. Shake well.
8.6.2 Observe color. A violet solution means the original oil sample contains less than 1000 mg/kg total chlorine. A yellow or colorless solution means the oil sample contains greater than 1000 mg/kg total chlorine.
8.7 Method B (Quantitative to 4000 mg/kg) - Fill the 1 cc tuberculin syringe with 13.7 mmol/L of mercuric nitrate solution to a volume of 1.0 mL by placing the tip of the syringe in the mercuric nitrate solution and withdrawing the plunger slowly until the syringe is full. If a burette is used instead of a syringe, fill the burette with the mercuric nitrate solution and dispense solution until the meniscus is at the zero point.
8.7.1 Add approximately 0.5 mL of diphenylcarbazone solution to the 5 mL of aqueous filtrate and mix well.
8.7.2 Place the filled tuberculin syringe in the polyethylene tube containing the aqueous filtrate and indicator reagent, and slowly depress the syringe so that the mercuric nitrate titrant is dispensed drop by drop. If the burette is used, add titrant drop by drop. Gently shake the solution between each drop. Stop titrating when a persistent violet color remains throughout the solution.
8.7.3 Examine the titrating syringe and determine where the tip of the plunger is in relation to the scale marked on the outside of the syringe barrel. Determine the amount of titrant (to the nearest 0.025 mL) that has been used.
