1、Designation: D2158 11D2158 16Designation: 317/95Standard Test Method forResidues in Liquefied Petroleum (LP) Gases1This standard is issued under the fixed designation D2158; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year
2、of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of extraneous materials weathering above 38C38 C that are present in liq
3、uefiedpetroleum gases.The extraneous materials will generally be dissolved in the LPG, but may have phase-separated in some instances.1.2 Liquefied petroleum gases that contain certain anti-icing additives can give erroneous results by this test method.1.3 Although this test method has been used to
4、verify cleanliness and lack of heavy contaminants in propane for many years,it might not be sensitive enough to protect some equipment from operational problems or increased maintenance.Amore sensitivetest, able to detect lower levels of dissolved contaminants, could be required for some application
5、s.1.4 WARNINGMercury has been designated by many regulatory agencies as a hazardous material that can cause centralnervous system, kidney and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Cautionshould be taken when handling mercury and mercury containin
6、g products. See the applicable product Material Safety Data Sheet(MSDS) for details and EPAs websitehttp:/www.epa.gov/mercury/faq.htmfor additional information. Users should be awarethat selling mercury and/or mercury containing products into your state or country may be prohibited by law.1.4 The va
7、lues stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate
8、 safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D96 Test Method for Water and Sediment in Crude Oil by Centrifuge Method (Field Procedure) (Withdrawn 2000)3D1796 Test Method for Water and Sediment in Fuel O
9、ils by the Centrifuge Method (Laboratory Procedure)D1835 Specification for Liquefied Petroleum (LP) GasesE1E1137 Specification for ASTM Liquid-in-Glass Industrial Platinum Resistance ThermometersE2251 Specification for Liquid-in-Glass ASTM Thermometers with Low-Hazard Precision LiquidsE2877 Guide fo
10、r Digital Contact Thermometers2.2 Energy Institute Document:IP Test Methods - Appendix A. Specifications - IP standard thermometers43. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 oil stain observation, nthe volume of solvent-residue mixture required to yield an oil stain or r
11、ing that persists for 2minutes 2 min under specified conditions on absorbent paper.3.1.2 residue, nthe volume, measured to the nearest 0.05 mL, 0.05 mL, of the residual material boiling above 38C38 Cresulting from the evaporation of 100 mL 100 mL of sample under the specified conditions of this test
12、 method.1 This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products Products, Liquid Fuels, and Lubricants and is the direct responsibility ofSubcommittee D02.H0 on Liquefied Petroleum Gas.Current edition approved Jan. 1, 2011Dec. 1, 2016. Published February 2011January
13、2017. Originally approved in 1963. Last previous edition approved in 20052011 asD2158D2158 11.05. DOI: 10.1520/D2158-11.10.1520/D2158-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume in
14、formation, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been
15、 made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.
16、*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.1.3 solvent-residue mixture, na mixture (solution) of 10 mL 10 mL of solvent with any residue remaining in the centrifu
17、getube at the conclusion of the first step in this test method.4. Summary of Test Method4.1 A 100-mL100 mL sample of liquefied petroleum gas is weathered in a 100-mL100 mL centrifuge tube. The volume ofresidue remaining after heating the tube to 38C38 C is measured and recorded.4.2 To dissolve any r
18、esidue, 10 mL 10 mL of solvent is added to the centrifuge tube. Small, measured volumes ofsolvent-residue mixture are deposited on an absorbent paper in a specified manner. The appearance of the absorbent paper to whichthe residue solution has been added in measured increments is observed and record
19、ed.5. Significance and Use5.1 Control over the residue content (required by Specification D1835) is of considerable importance in end-use applicationsof LPG. In liquid feed systems, residues can lead to troublesome deposits and, in vapor withdrawal systems, residues that arecarried over can foul reg
20、ulating equipment. Those that remain will accumulate, can be corrosive, and will contaminate followingproduct. Water, particularly if alkaline, can cause failure of regulating equipment and corrosion of metals.6. Interferences6.1 Solid contaminants such as rust, scale or dirt can interfere with this
21、 test method, which is not intended for representativemeasurement of solid, undissolved contaminants.7. Apparatus7.1 Centrifuge Tube, 100-mL100 mL graduated, conforming to dimensions given in Fig. 1. The first 0.5 mL 0.5 mL shall begraduated in 0.05-mL0.05 mLincrements. The shape of the lower tip of
22、 the tube is especially important. The taper shall be uniformand the bottom shall be rounded as shown in Fig. 1. Tubes shall be made of thoroughly annealed heat-resistant glass. Volumetricgraduation tolerances, based on air-free water at 20C,20 C, are given in Table 1. Detailed requirements for cent
23、rifuge tubesappear in Test Methods D96 and D1796.7.2 Cooling Coil and Cooling Bath, a minimum length of 6 m 6 m of 55 mm to 7-mm7 mm outside diameter copper tubingwound to a diameter of 63.563.5 mm 6 1.5-mm1.5 mm outside diameter, and assembled in a suitable cooling bath. (See Fig. 2as an example.)7
24、.2.1 Mechanical refrigeration is permitted provided that the coolant temperature is below 43C.43 C. If dry ice is used, anon-glass dewar or vessel is recommended.7.3 Syringe, 2-mL2 mL graduated in 0.1 mL and equipped with a needle 200200 mm 6 5 mm 5 mm long. The needle may beeither a sharp needle (o
25、rdinary medical syringe needle) or a safe, non-sharp syringe needle to avoid a puncture hazard.Alternatively, an equivalent liquid dispensing device capable of delivering 0.1-mL0.1 mL increments may be used, such as a0.1-mL pipette.0.1 mL pipet.7.4 Temperature Measuring Device, that is intrinsically
26、 safe, with accuracy equal to or better than liquid-in-glass thermometerASTM S5C described in Specification E1E2251 or IP. Guide E2877 Test Methods - Appendix A shall be used. Thermometersconforming to and Specification E1E1137 or IPAppendixAhave been found to be satisfactory.may be useful for selec
27、ting a digitalcontact thermometer.Low Range 38C to + 50C IP 1C/ASTM 5Cor IP 2C/ASTM 6CHigh Range 20C to + 50C ASTM 57C7.4.1 For routine testing, a general purpose thermometer or a digital contact thermometer with 0.5 C subdivisions or displayresolution and a maximum error of 0.5 C may be used.NOTE 1
28、When a thermometer or a water bath, or both, are not available, for example when conducting a field test, a satisfactory alternative forscreening purposes is to warm the tip of the centrifuge tube with the hand.7.4.1 For routine testing, a general purpose thermometer with 0.5C subdivisions and a max
29、imum scale error of 0.5C may beused.7.5 Absorbent Paper, white, at least 100-mm100 mm diameter. Medium grade or rapid filter paper has been found to besatisfactory. In this test method, the paper will be referred to as “filter paper.”7.6 Solvent Wash Bottle, typically polyethylene.7.7 Water Bath, co
30、ntrolled at 3838 C 6 2C.2 C.7.8 Copper Wire, 11 mm to 2-mm2 mm diameter, at least 10 mm 10 mm longer than the centrifuge tubes height.7.9 Clamp, suitable for holding the centrifuge tube during weathering.D2158 1628. Reagents and Materials8.1 SolventHPLC-grade pentane or cyclopentane. Another grade o
31、f solvent may be used provided that it meets therequirements of 10.2.FIG. 1 Cone-Shaped Centrifuge Tube, 203 mm203 mmTABLE 1 Centrifuge Tube Graduation TolerancesRange, mL Scale, Division,mL Limit of Error,mL0.0 to 0.1 0.05 0.020.1 to 0.3 0.05 0.030.3 to 0.5 0.05 0.050.5 to 1.0 0.1 0.051.0 to 3.0 0.
32、1 0.13.0 to 5.0 0.5 0.25.0 to 25.0 1.0 0.525.0 to 100.0 1.0 1.0D2158 1638.1.1 Although pentane is the preferred solvent for use in this test method, cyclopentane may be substituted for pentanewhenever the ambient temperature or altitude is too high to enable the convenient handling of pentane.8.1.2
33、Storage of solvent in a polyethylene wash bottle for several days contaminates the solvent. Therefore, do not use anysolvent that has remained in a polyethylene wash bottle for more than one day.9. Hazards9.1 Note that there is a significant fire hazard from LPG vapors, and since the boiling point o
34、f LPG can be as low as41C,41 C, there is a risk of freezing “burns.” Take appropriate safety precautions to prevent ignition or fire, and wear suitableprotective equipment to protect against skin contact with liquid or vaporizing LPG.9.2 Operators should wear a grounded antistatic wrist strap. The u
35、se of an antistatic floor mat and grounding the sample cylinderare also advised.10. Preparation of Apparatus10.1 Wash all glassware that is to be used in the test in the selected solvent.10.2 Verification of cleanliness of glassware and solvent.10.2.1 Add 10 mL of a new sample of solvent to the cent
36、rifuge tube.10.2.2 Mark the center of the filter paper with a pencil or other non-pentane-soluble writing tool.10.2.3 Fill the syringe or equivalent liquid dispensing device (see 7.3) with a portion of the solvent drawn from the centrifugetube and direct 0.1-mL0.1 mL portions of the solvent to the m
37、ark on the paper.10.2.3.1 The solvent is added in 0.1-mL0.1 mL increments to confine the solvent ring to a circle about 3030 mm to 35 mm35 mm in diameter. The filter paper should be held level during the solvent addition. One method is to place it on a 250-mL250 mLbeaker.10.2.4 Allow the solvent to
38、evaporate for 2 min, 2 min, and note the persistence of an oil ring.10.2.4.1 The presence of an oil ring shall be observed by holding the dry filter paper between the eye and a bright incandescentlight or strong daylight.NOTE 1Coils in the drawing are extended for clarity.FIG. 2 Precooling Equipment
39、D2158 16410.2.4.2 If no oil ring appears after 1.5 mL 1.5 mL of solvent has been added, the solvent and glassware are satisfactory.10.2.4.3 The appearance of an oil ring indicates either improperly cleaned glassware or contaminated solvent.11. Procedure11.1 Residue Measurement:11.1.1 If the LPG samp
40、le is expected to be clean, with no residues or contaminants that could result in an oil stain, the proceduremay be performed without a cooling coil. However, if a residue or oil stain is detected using this screening procedure (that is, aresidue is measured at greater than or equal to 0.05 mL 0.05
41、mL in 11.1.7, or an oil stain is generated with 1.5 mL of test solutionin 11.2.4), the test shall be repeated using a cooling coil.11.1.2 Attach the cooling coil to the LPG sample source, cool the coil to below the boiling point of the sample, and flush thecoil and sampling line.11.1.3 Rinse and coo
42、l the centrifuge tube with the material to be sampled and then fill it to the 100-mL100 mL mark with arepresentative sample of LPG.11.1.4 Immediately insert the copper wire through a clean, slotted cork or a clean, loose-fitting plug of cotton or cleansing tissuein the mouth of the centrifuge tube.
43、The wire helps to prevent superheating and resulting bumping (erratic or excessive boiling),and the cork (or plug) will keep out air or moisture while the sample is weathering.11.1.5 If more than 10 mL of the sample is lost because of bumping, obtain a new sample and repeat the test.11.1.6 Allow the
44、 sample to weather, using artificial heating if the ambient temperature or type of sample requires it. If, whenweathering has ceased and the tube has reached ambient temperature, a visible residue remains, place the tip of the tube in a waterbath at 38C38 C for 5 min.5 min.11.1.7 Record the volume o
45、f any remaining residue to the nearest 0.05 mL, 0.05 mL, and the presence of extraneous matter, ifobserved.11.1.8 Perform the oil stain observation described in 11.2 even if there is no apparent or visible residue in the centrifuge tube.Experience has shown that there can be a thin film of oil on th
46、e inner surface of the centrifuge tube that is difficult to see and doesnot give a measurable volume, but can still give a ring or stain in the Oil Stain Observation procedure.11.2 Oil Stain Observation:11.2.1 Add sufficient solvent to the centrifuge tube containing the residue described in 11.1.6 t
47、o restore the volume to 10 mL.10 mL. Add the solvent from the wash bottle and carefully wash down the sides of the tube. Stir well so that any residue at thebottom of the tube is dissolved uniformly in the solvent. Stirring with the syringe needle (see 7.3) or pipette has been foundsatisfactory. Thi
48、s mixture will be referred to as the solvent-residue mixture.11.2.2 Mark the center of a clean white filter paper.11.2.3 Fill the syringe or equivalent liquid dispensing device (see 7.3), and direct 1.5 mL 1.5 mL of the solvent-residue mixtureat the center of the paper at an appropriate rate such th
49、at the wetted circle is maintained at about 3030 mm to 35 mm in diameter.If desired, steps 11.2.3 and 11.2.4 may be omitted, and the test continued according to 11.2.5.11.2.4 After directing the entire 1.5 mL 1.5 mL of residue solution onto the filter paper and at the end of a 2-min2 min waitingperiod, if no oil ring persists when holding the dry filter paper between the eye and a bright incandescent light or strong daylight,discontinue the test and go to 12.1.11.2.5 If a stain or ring is discernible, determine the volume of the solv
