SH/T 0093-1991 Determination of solid particulate contaminants in jet fuels

AI-translated method card — human verification pending. This is not an official translation of the standard. Unclear source values remain unverified; check the original standard and product certificate before use.

Card type: Test method

1. Method number / full name / English name / replacement relationship

• Method number: SH/T 0093-91
• Full name: Determination of solid particulate contaminants in jet fuels
• English name: not provided in the available source
• Replacement relationship: replaces SY 2229-82
• Approval/implementation: approved by China Petrochemical Corporation 1991-11-26, implemented on 1992-01-01
• Reference adoption: ASTM D2276-88 "Determination of particulate contaminants in aviation turbine fuels" and United States military standard MIL-T-5624N appendix A "Method for determination of JP-4, JP-5 filtration time and total solid particles"

2. Scope of application and non-applicability

• Scope of application: This standard specifies a laboratory method for determining the content of solid particulate contaminants in jet fuels; it is applicable to jet fuels.
• Non-applicability: not provided in the available source.

3. Method principle

Under specified conditions, the sample is filtered through a glass frit filtration apparatus; the weight gain on the microporous membrane filter disc is the total contaminant content of the sample, expressed as mg/L. If the color rating of the microporous membrane filter disc and the filtration time need to be determined for the sample, use the method in appendix A.

4. Reagents and materials (purity / preparation)

• Petroleum ether: analytical reagent, 30~60℃.
• Microporous membrane filter discs (abbreviated as membrane filter discs): two pieces, flat diameter 47~50 mm, nominal pore size 0.8 μm (the source source-text extraction is "0.8km", requires confirmation against the source standard (source-text extraction)), the mass of each membrane filter disc shall not exceed 0.1 g.
• Oil-resistant rubber rings for appendix A: thickness about 0.5 mm, central hole diameter 24.5–25.0 mm, outer ring diameter 50–60 mm.
• Membrane filter disc color standard for appendix A: there are three color bands, red, yellow and gray, represented by the letters "A", "B" and "G" respectively; each color band is divided into 11 levels, with rating values set as 0~10.

5. Apparatus and equipment

• Analytical balance: sensitivity 0.1 mg, pan diameter greater than 50 mm.
• Oven: an air circulation fan should not be used, controlled temperature is 90±5℃ (the source source-text extraction is "905C", requires confirmation against the source standard (source-text extraction)).
• Petri dish: diameter 125 mm, with a movable glass support inside.
• Tweezers: flat tips, without serrations.
• Vacuum system: vacuum degree not less than 80 kPa.
• Suction flask: 5 L.
• Glass frit filtration apparatus (see figure 1): includes a funnel and a funnel base lined with a glass frit; the microporous membrane filter disc can be clamped between the two and secured with aluminum metal clips; dimensions are given in appendix B and appendix C.
• Solvent filter (see figure 2): includes a stainless steel filter disc holder, filter disc (nominal pore size 0.65 μm, flat diameter 25 mm), 500 mL suction flask and a double-bulb hand pump; dimensions are given in appendix D.
• Appendix A: stopwatch; membrane filter disc color standard; oil-resistant rubber ring.

6. Recommended operating conditions

• Oven temperature: 90±5℃.
• Vacuum degree: not less than 80 kPa; after filtering 3 min, the system vacuum degree should reach 80 kPa.
• Filtration time determination for appendix A: after starting 1 min, maintain the vacuum degree at 80~90 kPa.
• Membrane filter disc soaking: soak in filtered petroleum ether for about 100 mL for about 20 min.
• Membrane filter disc drying: dry in an oven at 90±5℃ for 30 min.
• Placement before weighing: after removal from the oven, place near the balance to await weighing, with the dish cover slightly open; weigh after 40 min.
• Petroleum ether rinsing: at least 50 mL; immerse the membrane filter disc for about 30 s.

7. Sampling and sample preparation

• Sampling shall be carried out in accordance with GB 4756.
• Sample amount is 4~5 L, accurate to 0.1 L.
• Sample amount for appendix A is 4 L, accurate to 0.1 L.
• Apparatus preparation: clean the glass frit filtration apparatus, Petri dishes and glass supports with cleaning agent, then rinse with tap water and distilled water; use the solvent filter to rinse the above apparatus with filtered petroleum ether; after several seconds, dry in air or in an oven, and cover well with plastic sheeting that has been rinsed through the solvent filter.
• Membrane filter disc preparation: carefully use tweezers to immerse two membrane discs in a Petri dish containing about 100 mL of filtered petroleum ether and soak for about 20 min; place them separately in two marked Petri dishes, with the membrane filter discs leaning against the glass supports in the dishes; slightly open the two Petri dishes and dry in an oven at 90±5℃ for 30 min; after removal, place near the balance to await weighing, with the dish cover slightly open; after 40 min, use tweezers to respectively grip the edges of the membrane filter discs and place them on the balance for weighing, the membrane filter disc should be placed in the center of the weighing pan; use tweezers to respectively clamp the two membrane filter discs at the joint of the glass frit filtration apparatus, the upper one is called the test membrane filter disc, and the lower one is called the control membrane filter disc, then secure the glass frit filtration apparatus with aluminum metal clips.

8. Analysis procedure

• 7.1 Shake the sample bottle vigorously for about half a minute, and first pour a portion of the sample into the filter funnel.
• 7.2 Start the vacuum pump to carry out filtration; after 3 min, the system vacuum degree should reach 80 kPa.
• 7.3 Before each addition of sample, stir the sample, and always maintain a liquid head in the funnel of the glass frit filtration apparatus.
• 7.4 After the sample has been filtered, record the volume of sample filtered, and use the solvent filter to rinse the inner wall of the sample bottle with at least 50 mL of petroleum ether, then pour it all into the funnel of the frit filtration apparatus, so that contaminants are transferred to the membrane filter disc as completely as possible.
• 7.5 After venting the system, stop the vacuum pump. Rinse the inner wall of the funnel of the frit filtration apparatus with petroleum ether through the solvent filter, and let the petroleum ether immerse the membrane filter disc for about 30 s. Then start the vacuum pump again; after the petroleum ether has been completely drawn off for several seconds, stop the vacuum pump and vent.
• 7.6 Carefully remove the aluminum metal clips and funnel, use tweezers to carefully remove the test membrane filter disc and control membrane filter disc from the funnel base of the frit filtration apparatus, and place them separately in two marked covered Petri dishes.
• 7.7 According to the steps described in 6.3.2, 6.3.3 and 6.3.4, dry and weigh the membrane filter discs, taking care not to disturb the contaminants on the surface of the membrane filter discs.

9. Qualitative and quantitative determination and calculation formula

The solid particulate contaminant content of the sample (mg/L) is calculated according to the following formula:

Where:

• m₁——mass of the test membrane filter disc after the test, g;
• m₂——mass of the test membrane filter disc before the test, g;
• m₃——mass of the control membrane filter disc after the test, g;
• m₄——mass of the control membrane filter disc before the test, g;
• V—— actual volume used for filtering the sample, L.

(The original formula expression source-text extraction is missing, requires confirmation against the source standard (source-text extraction))

10. Precision

Repeatability: the difference between two results obtained by repeated determination by the same operator shall not exceed the following values.

11. Report

Take the arithmetic mean of two results from repeated determination as the determination result. Round to 0.01 mg/L.

Appendix A report:

• Filtration time determination result report: after the sample has been filtered, report the filtration time as an integer "min". If the sample has not been completely filtered, report greater than 30 min [remaining sample volume (L)].
• Membrane filter disc color rating report: after the sample has been filtered, report the color band and level to which the membrane filter disc belongs, expressed respectively by letters and numbers, such as A-1, B-2, G-3, etc. If the sample has not been completely filtered, the actual volume of sample filtered shall be additionally reported, expressed as "L".

12. Referenced documents

• GB 4756 Petroleum and liquid petroleum products sampling method (manual method)
• ASTM D2276-88 (reference)
• MIL-T-5624N Appendix A (reference)

13. Source and verification

This page is an AI translation of the available Chinese method card. Human verification is pending. It is not an official translation of the standard. Check the source standard and product certificate before use.

14. Quick Q&A