ASTM-D4807:05(R2020) pdf free download – Standard Test Method for Sediment in Crude Oil by Membrane Filtration.
7.2 Liboratory Sample—Use only representative samples obtained as specified in Practice D4057 (API MPMS Chapter 8.1) or Practice D4177 (API MPMS Chapter 8.2) for this test method. Analyze samples within two weeks after taking the sample. Retaining samples longer may affect the results.
7.3 Sample Preparation—The following sample preparation and handling procedure shall apply.
7.3.1 Mix the test sample of crude oil at room temperature in the original container immediately (within 15 mm) before analysis to ensure complete homogeneity. A test sample drawn directly from a large volume dynamic mixing system shall be analyzed within 15 mm or else remix as follows:
Nnh 2—Analysis should follow mixing as soon as possible. The 15 mm interval mentioned above is a general guideline which may not apply to all crudes, especially some light crudes which do not hold water and sediment in suspension for even this short a time.
7.3.2 Mixing of the sample should not increase the temperature of the sample more than 10 °C (20 °F), or a loss of water may occur affecting the sample’s composition. The type of mixer depends on the quantity of crude. Before any unknown mixer is used, the specifications for the homogenization test, Practice D5854 (API MPMS Chapter 8.3), must be met. The mixer must be re-evaluated following any changes in the type of crude, quantity of crude, or shape of the sample container.
7.3.3 For small test sample volumes, 50 inL to 300 mL, a nonaerating, high-speed, shear mixer is required. Use the mixing time, mixing speed, and height above the bottom of the container found to he satisfactory in Practice D5854 (API MPMS Chapter 8.3). Clean and dry the mixer between samples.
8. Procedure
8.1 Filter Preparation—Prepare nylon filters by heating in an oven at 105 °C ± 2 °C (220 °F ± 4 °F) for 15 mm. Cool and store the dried filters in a cooling vessel (desiccator without desiccant) until needed. Use only new filters.
8.2 Weigh the filter immediately before use to the nearest
0.0001 g.
8.3 Using tweezers, place the membrane filter on the center of the filter support, which is mounted on the filtering flask with a rubber stopper. Attach the funnel to the filter support and clamp it securely.
8.4 Connect the heating coil to the circulating bath and place the coil around the lower part of the funnel. Set the temperature of the circulating bath so as to maintain the oil in the funnel at 90°C ± 2°C (195°F ± 4°F).
Nom 3—Care should be taken not to overheat the funnel so as to cause evaporation of the toluene and glazing of the filter.
8.5 Sample Addition—Into a 2(X) rnL beaker, weigh 1 0 g of a thoroughly mixed sample (see Section 7) to the nearest
0.0001 g. Add 100 mL of toluene to the beaker and heat the mixture with stirring to 90 °C ± 2 °C (195 °F ± 4 °F).
Maintain the temperature at 90 °C ± 2 °C (195 °F ± 4 °F) for about 15 mm to dissolve any wax in the crude.