API MPMS 10.8-2005 pdf download.Manual of Petroleum Measurement Standards Chapter 10—Sediment and Water Section 8—Standard Test Method for Sediment in Crude Oil by Membrane Filtration.
5. Apparatus 5.1 Funnel and Filter Support Assembly—Use an assembly designed to hold 47-mm diameter filters as was used in the development of this test method (see Fig. 1). 5 5.1.1 Filter Funnel—Use a filter funnel with a 250 mL minimum capacity. The lower part of the funnel has a 40-mm inside diameter and is designed to secure the 47-mm diameter filter against the filter support. The funnel can be jacketed to facilitate heating the solvent funnel and sample during filtering. N OTE 1—Use of a glass funnel should minimize the effect of static electricity when filtering. 5.1.2 Filter Support—Use a support base for the filter that has a porous scintered glass center section about 40 to 43 mm in diameter. The support base is designed to fit securely against the funnel holding the filter in place over the porous section. The filter support’s stem should be long enough to extend down into the filter flask such that the end is below the vacuum connection. 5.1.3 Clamp Assembly—Use a spring or screw type clamp to secure the funnel to the filter support. The clamp should be tight enough to prevent the solvent from leaking through at the junction between the glass and filter membrane. The exterior dimensions of the funnel and support are designed to facilitate clamping the two pieces together. 5.1.4 Rubber Stopper—Use a single-hole, capable of hold- ing the lower stem of the filter support securely onto the filtering flask. 5.1.5 Vacuum Filtering Flask—Use a 500 mL or larger vacuum filtering flask. 5.2 Membrane Filter—Use a nylon membrane filter, 47 mm in diameter with 0.45-μm pore size.
6. Reagents 6.1 Toluene—Reagent grade chemicals shall be used in all tests. 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, 7 or to Grade 2 of ISO 5272. Other grades may be used, provided it is first ascertained that the reagent’s lot or batch is of sufficiently high purity to permit its use without lessening the accuracy of the determination. (Warning—Flammable. Keep away from heat, sparks and open flame. Vapor harmful. Toluene is toxic. Particular care shall be taken to avoid breathing the vapors and to protect the eyes. Keep the container closed. Use with adequate ventilation. Avoid prolonged or repeated contact with the skin.) 7. Sampling, Test Specimens 7.1 Sampling, shall include all the steps required to obtain a representative portion ofthe contents ofany pipe, tank, or other system, and to transfer the sample into the laboratory test container. The laboratory test container and sample volume shall be ofsufficient dimensions and volume to allow mixing as described in 7.3.1. Mixing is required to properly disperse sediment as well as any water present in the sample. 7.2 Laboratory Sample—Use only representative samples obtained as specified in Practice D 4057 (API MPMS Chapter 8.1) or Practice D 4177 (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 prepara- tion and handling procedure shall apply.
8.7 Filter Washing—Before the last portion of sample has completely filtered, wash the funnel and filter with 50 mL of hot toluene (90°C, 195°F) until no oil is visible on the filter. With the vacuum on, leave the filter on the apparatus for 2 min. 8.8 Apparatus Disassembly—Disassemble the filter appara- tus by removing the clamp and funnel. Inspect the condition of the filter. If the filter has been properly mounted, it may not be necessary to wash the edges after disassembly. However, if upon removing the funnel dark spots are observed around the edge ofthe filter further washing is necessary. With the vacuum on, use a dropper to wash the filter’s edges with hot toluene (90°C, 195°F). 8.9 If the filter is completely or partially covered with black or dark brown crude oil residue after the washing step above, then discard the filter and repeat the test with a smaller sample size. N OTE 5—Normally the color ofthe sediment on the filter is gray or light tan. A black or deep brown colored deposit on the filter is indicative of incomplete washing.