GB/T 511-2010 Determination of mechanical impurities in petroleum and petroleum products and additives

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 title / English name / replacement relationship

• Standard number: GB/T 511-2010
• Chinese full title: Determination of mechanical impurities in petroleum and petroleum products and additives
• English name: Petroleum, petroleum products and additives—Method for determination of mechanical admixtures
• Replacement relationship: replaces GB/T 511-1988 "Determination of mechanical impurities in petroleum products and additives (gravimetric method)"
• Previous versions: GB/T 511—1965, GB/T 511—1977, GB/T 511—1988
• Adoption relationship: modified adoption of the former Soviet standard ГОСТ 6370—1983 (1997) "Determination of mechanical impurities in petroleum, petroleum products and additives", redrafted according to ГОСТ 6370—1983 (1997)
• Issued/implemented: issued on 2010-09-02, implemented on 2010-12-01
• Proposed/administrated by: proposed by the National Technical Committee for Standardization of Petroleum Products and Lubricants; administrated by the Subcommittee on Petroleum Fuels and Lubricants of the National Technical Committee for Standardization of Petroleum Products and Lubricants
• Drafting organization: North China Research Institute of Sinopec Sales Co., Ltd.
• Drafter: Chen Chunhui

2. Scope of application and non-applicability

• Scope of application: applicable to the determination of mechanical impurities in petroleum, liquid petroleum products and additives.
• Not applicable: not applicable to lubricating greases and asphalt.
• Method overview (Chapter 1): the sample is filtered with a quantitative filter paper or a sintered-glass filter of constant weight to determine mechanical impurities.

3. Method principle

Weigh a certain amount of sample, dissolve it in the solvent used, filter with a filter paper or sintered-glass filter of constant weight, and the impurities retained on the filter paper or sintered-glass filter are the mechanical impurities. (Chapter 3 Method summary)

4. Reagents and materials (purity / preparation)

4.1 Reagents

• 5.1.1 95% ethanol: chemically pure
• 5.1.2 diethyl ether: chemically pure
• 5.1.3 toluene: chemically pure
• 5.1.4 ethanol-toluene mixed solvent: prepared from 95% ethanol and toluene in a volume ratio of 1:4
• 5.1.5 ethanol-diethyl ether mixed solvent: prepared from 95% ethanol and diethyl ether in a volume ratio of 4:1
• Note 1: before use, all the above reagents shall be filtered with the same type of filter paper or sintered-glass filter as used in the test, and then used as solvent.
• Note 2: during the test, reagents of a grade not lower than that specified in the standard are permitted.
• 5.1.6 silver nitrate: analytically pure, prepared as an aqueous solution of 0.1 mol/L
• 5.1.7 water: meets the requirements for grade three water in GB/T 6682

4.2 Materials

• 5.2.1 quantitative filter paper: medium speed, diameter 11 cm (the source source-text extraction writes "11cp", requires confirmation against the source standard (source-text extraction)), meets the requirements of GB/T 1914 standard
• 5.2.2 solvent naphtha: meets the requirements of SH 0004 standard
• Note: before use, it shall be filtered with the same type of filter paper or sintered-glass filter as used in the test, and then used as solvent.

5. Apparatus and equipment

• 4.1 beaker or wide-neck conical flask
• 4.2 weighing bottle
• 4.3 glass funnel
• 4.4 insulated funnel
• 4.5 wash bottle
• 4.6 glass rod
• 4.7 suction flask
• 4.8 water bath or electric hot plate
• 4.9 vacuum pump or water jet pump: ensures residual pressure not greater than 1.33×10⁰ Pa (the source source-text extraction writes "1.33×10° Pa", requires confirmation against the source standard (source-text extraction))
• 4.10 desiccator
• 4.11 oven: can be heated to 105 ℃±2 ℃
• 4.12 infrared lamp
• 4.13 sintered-glass filter: funnel type, P10 (pore size 4 μm~10 μm), diameter 40 mm, 60 mm, 90 mm
• 4.14 analytical balance: sensitivity 0.1 mg

6. Recommended operating conditions

• Oven drying temperature: 105 ℃±2 ℃ (6.3, 7.7)
• First drying time: not less than 45 min (6.3, 7.7)
• Second drying time: 30 min (6.3, 7.7)
• Desiccator cooling time: 30 min (6.3, 7.7; the source 6.3 source-text extraction writes "[unreadable characters]⑧[unreadable character]oin", requires confirmation against the source standard (source-text extraction))
• Solvent preheating temperature: solvent naphtha 40 ℃; toluene 80 ℃ (7.1.2)
• Upper limit of hot filtration temperature: solvent naphtha solution heated to not more than 40 ℃; toluene solution heated to not more than 80 ℃ (7.4)
• Rinsing temperature: solvent naphtha not more than 40 ℃ (7.5); toluene not more than 80 ℃ (7.5.1); ethanol-toluene mixed solvent heated to 60 ℃ (7.5.2)
• Hot distilled water rinsing: heated to 80 ℃, amount 200 mL~300 mL (7.6)
• Suction filtration speed: controlled so that the filtrate forms drops, not a stream (7.4)

7. Sampling and sample preparation

• 6.1 Shake the sample in the container (not exceeding three quarters of the container volume) for 5 min to mix uniformly. Paraffinic and viscous petroleum products shall be preheated to 40 ℃, and lubricant additives heated to 70 ℃~80 ℃, then carefully stirred with a glass rod for 5 min.
• 6.2 The test filter paper shall be weighed in a clean, dry weighing bottle.
• 6.3 Place the open weighing bottle with filter paper or the sintered-glass filter in the oven, dry at 105 ℃±2 ℃ for not less than 45 min, then place in a desiccator to cool for 30 min (the cap of the weighing bottle shall be closed), and weigh to the nearest 0.000 2 g. Repeat drying (the second drying time only needs 30 min) and weighing until the difference between two consecutive weighings does not exceed 0.000 4 g.
• Table 1 Sample mass and dilution ratio for different samples (the source source-text extraction table is incomplete; the following is the identifiable content, requires confirmation against the source standard (source-text extraction)):

Note: In Table 1, the sample mass, weighing precision, and dilution ratio for the two rows of "petroleum products" are incomplete in the source source-text extraction (numbers such as 0.05, 0.03, 2–4, 4–6 appear but their correspondence is unclear), requires confirmation against the source standard (source-text extraction).

8. Analysis procedure

• 7.1 According to the requirements of Table 1, add the mixed sample to a beaker and weigh it (at least able to accommodate the total volume after diluting the sample), and dilute it in proportion with heated solvent (solvent naphtha or toluene).
  • 7.1.1 When determining mechanical impurities in petroleum, dark petroleum products, additive-containing lubricating oils and additives, toluene is used as the solvent.
  • 7.1.2 The solvent naphtha or toluene used to dissolve the sample shall be preheated in a water bath to 40 ℃ and 80 ℃ respectively, and the solvent shall not be boiled.
• 7.2 Place the constant-weight filter paper in a glass funnel. Fix the funnel holding the filter paper or the constant-weight sintered-glass filter with a stand, and filter the sample solution while hot. The solution flows along the glass rod into the funnel (filter paper) or sintered-glass filter; during filtration, the height of the solution shall not exceed three quarters of the funnel (filter paper) or sintered-glass filter. Rinse the residue on the beaker with hot solvent naphtha (or toluene) and pour it into the funnel (filter paper) or sintered-glass filter. Loosen the sample residue and solid impurities adhering to the beaker wall with a glass rod, and rinse them onto the filter paper or sintered-glass filter with solvent naphtha heated to 40 ℃ (or toluene heated to 80 ℃). Repeat rinsing the beaker until a drop of the solution on the filter paper no longer leaves an oil stain after evaporation.
• 7.3 If the sample contains water and is difficult to filter, let the sample solution stand for 10 min–20 min, then carefully pour the solvent naphtha (or toluene) solution above the sediment in the beaker into the funnel or sintered-glass filter. Thereafter, add (5–15) times (by volume) of ethanol-diethyl ether mixed solvent to the sediment in the beaker to dilute it, then filter again; the residue in the beaker shall be thoroughly rinsed into the filter paper or sintered-glass filter with ethanol-diethyl ether mixed solvent and hot solvent naphtha (or toluene).
• 7.4 When determining difficult-to-filter samples, measures such as vacuum suction filtration and a heated funnel or infrared lamp heating are permitted. For vacuum filtration, the filter funnel may be mounted on a suction flask with a rubber stopper, and the suction flask connected to a vacuum pump. The filter paper is moistened with solvent so that it adheres completely to the funnel wall; the height of the poured solution should not exceed three-quarters of the filter paper or fritted glass filter; after the previous portion of solution has completely drained, add a new portion of solution. The suction filtration speed should be controlled so that the filtrate forms drops, and a continuous stream is not permitted. During hot filtration, the solution being filtered should not be boiled; the solvent oil solution is heated to not more than 40 ℃, and the toluene solution is heated to not more than 80 ℃.
  • Note 1: A new fritted glass filter must be treated with chromic acid cleaning solution before use, then rinsed clean with distilled water, placed in a drying oven to dry, and kept for later use. After the test is completed, it should be soaked in chromic acid cleaning solution for 4 h~5 h, then rinsed clean with distilled water, dried, and placed in a desiccator for later use.
  • Note 2: When a dispute arises between results measured using a fritted glass filter and filter paper in a test, the result obtained by filter paper filtration shall prevail.
• 7.5 After filtration is completed, for the filter paper or fritted glass filter carrying the precipitate, wash with a wash bottle containing not more than 40 ℃ solvent oil until no trace of the sample remains on the filter paper or fritted glass filter, and the filtered solvent is completely transparent and colorless.
  • 7.5.1 When determining mechanical impurities in petroleum, dark petroleum products, additive-containing lubricating oils, and additives, use not more than 80 ℃ toluene to rinse the filter paper or fritted glass filter.
  • 7.5.2 When determining mechanical impurities in additives and additive-containing lubricating oils, if there is residue in the filter paper or fritted glass filter that is insoluble in solvent oil and toluene, additionally rinse with an ethanol-toluene mixed solvent heated to 60 ℃.
• 7.6 When determining mechanical impurities in additives and additive-containing lubricating oils, it is permitted to use hot distilled water to rinse the residue. After rinsing the filter paper or fritted glass filter carrying the precipitate with solvent, dry in air for 30 min–15 min (thus in the source text, requires confirmation against the source standard (source-text extraction)), then rinse with distilled water of 200 mL–300 mL heated to 80 ℃. If determining mechanical impurities in petroleum, rinse with hot water until no chloride ions are present in the filtrate, and use 0.1 mol/L silver nitrate solution to test for the presence of chloride ions in the filtrate. If the filtrate is not turbid, it means there are no chloride ions.
• 7.7 After rinsing of the filter paper or fritted glass filter carrying the precipitate is completed, place the filter paper carrying the precipitate into the corresponding weighing bottle used before filtration; place the open weighing bottle or fritted glass filter in an oven at 105 ℃±2 ℃ and dry for not less than 45 min. Then place in a desiccator to cool for 30 min (the cap of the weighing bottle should be closed), and weigh to the nearest 0.000 2 g. Repeat the drying (the second drying only requires 30 min) and weighing operations until the difference between two consecutive weighings does not exceed 0.000 4 g.
• 7.8 If the mechanical impurity content does not exceed the required range of the technical specification for the petroleum product or additive (thus in the source text, requires confirmation against the source standard (source-text extraction)), the second drying and weighing operation may be omitted.
• 7.9 During the test, a blank test correction for the solvent should be carried out simultaneously.

9. Qualitative and Quantitative Determination and Calculation Formula

The mechanical impurity content of the sample w% (mass fraction) is calculated according to formula (1):

w = [(m2 − m1) − (m4 − m3)] / m5 × 100 … (1)

Where:

• m1: mass of the filter paper and weighing bottle (or mass of the fritted glass filter), in grams (g);
• m2: mass of the filter paper and weighing bottle with mechanical impurities (or mass of the fritted glass filter with mechanical impurities), in grams (g);
• m3: mass of the filter paper and weighing bottle before filtration in the blank test (or mass of the fritted glass filter), in grams (g);
• m4: mass of the filter paper and weighing bottle after filtration in the blank test (or mass of the fritted glass filter), in grams (g);
• m5: mass of the sample, in grams (g).

Note: The original source-text extraction formula layout is incomplete (rendered as “w= (m2[unreadable separator]m) (ms-ma2 × 100”); the above formula has been organized according to 7.9 blank test correction and the symbol explanations in the formula, requires confirmation against the source standard (source-text extraction).

10. Precision

Judge the reliability of the determination results according to the following provisions (95% confidence level).

• 10.1 Repeatability: the difference between two test results continuously measured for the same sample by the same operator using the same instrument in the same laboratory shall not exceed the value specified in Table 2.
• 10.2 Reproducibility: the difference between two single, independent test results measured for the same sample by different operators in different laboratories using different instruments shall not exceed the value specified in Table 2.

Table 2 Repeatability and Reproducibility

11. Report

• 9.1 Take the arithmetic mean of two repeat determination results as the test result.
• 9.2 When the mechanical impurity content is at or below 0.005% (mass fraction) (including 0.005%), it may be considered that there are no mechanical impurities.

12. Referenced Documents

• GB/T 1914 Chemical analysis filter paper
• GB/T 6682 Water specifications and test methods for analytical laboratories (GB/T 6682—2008, ISO 3696:1987, MOD)
• SH 0004 Solvent oil for the rubber industry

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 Reference Q&A