1、Designation: D 4045 04An American National StandardStandard Test Method forSulfur in Petroleum Products by Hydrogenolysis andRateometric Colorimetry1This standard is issued under the fixed designation D 4045; the number immediately following the designation indicates the year oforiginal adoption or,
2、 in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This test method covers the determination of sulfur inpetroleum products in th
3、e range from 0.02 to 10.00 mg/kg.1.2 This test method may be extended to higher concentra-tion by dilution.1.3 This test method is applicable to liquids whose boilingpoints are between 30 and 371C (86 and 700F). Materialsthat can be analyzed include naphtha, kerosine, alcohol, steamcondensate, vario
4、us distillates, jet fuel, benzene, and toluene.1.4 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.4.1 Certain specifications for the recorder (see 5.5) areexcepted.1.5 This standard does not purport to address all of thesafe
5、ty concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D 1193 Specification for Reagent
6、 WaterD 6299 Practice for Applying Statistical Quality AssuranceTechniques to Evaluate Analytical Measurement SystemPerformance3. Summary of Test Method3.1 The sample is injected at a constant rate into a flowinghydrogen stream in a hydrogenolysis apparatus. The sampleand hydrogen are pyrolyzed at a
7、 temperature of 1300C, orabove, to convert sulfur compounds to hydrogen sulfide (H2S).Readout is by the rateometric detection of the colorimetricreaction of H2S with lead acetate. Condensable components areconverted to gaseous products, such as methane, during hydro-genolysis.4. Significance and Use
8、4.1 In many petroleum refining processes, low levels ofsulfur in feed stocks may poison expensive catalysts. This testmethod can be used to monitor the amount of sulfur in suchpetroleum fractions.4.2 This test method may also be used as a quality-controltool for sulfur determination in finished prod
9、ucts.5. Apparatus3,45.1 Pyrolysis FurnaceA furnace that can provide anadjustable temperature from 900 to 1400C in a 5-mm insidediameter or larger tube is required to pyrolyze the sample. Thefurnace entry temperature shall allow insertion of the hypoder-mic tip to a depth at which the temperature is
10、550C to providesample vaporization at the injection syringe tip. This tempera-ture shall be above the boiling point of the sample and of thesulfur compounds in the sample (see Fig. 1). The pyrolyzertube may be of quartz; however, the lifetime is limited above1250C. Ceramic may be used at any tempera
11、ture.5.2 Rateometric H2S Readout Hydrogenolysis productscontain H2S in proportion to sulfur in the sample. The H2Sismeasured by measuring rate of change of reflectance caused bydarkening when lead sulfide is formed. Rateometric electron-ics, adapted to provide a first derivative output, allows suffi
12、-cient sensitivity to measure below 0.1 mg/L (see Fig. 2).5.3 Hypodermic SyringeA hypodermic having a needlelong enough to reach the 550C zone is required. A side port isconvenient for vacuum filling and for flushing the syringe. A1This test method is under the jurisdiction of ASTM Committee D02 onP
13、etroleum Products and Lubricants and is the direct responsibility of SubcommitteeD02.03 on Elemental Analysis.Current edition approved May 1, 2004. Published June 2004. Originallyapproved in 1987. Last previous edition approved in 1999 as D 404599.2For referenced ASTM standards, visit the ASTM websi
14、te, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3The apparatus described in 5.1-5.4 inclusive is similar in specification to theequipment available from Houston
15、Atlas, Inc., 22001 North Park Dr., Kingswood,TX 77339-3804. For further information see Drushel, H. V., “Trace SulfurDetermination Petroleum Fractions,” Analytical Chemistry, Vol 50, 1978, p. 76.4The sole source of supply of the apparatus known to the committee at this timeis Houston Atlas, Inc. If
16、you are aware of alternative suppliers, please provide thisinformation to ASTM International Headquarters. Your comments will receivecareful consideration at a meeting of the responsible technical committee,1whichyou may attend.1*A Summary of Changes section appears at the end of this standard.Copyr
17、ight ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.100-L syringe is satisfactory for injection rates down to 3L/min and a 25-L syringe for lower rates. (WarningExercise caution as hypodermics can cause accidental injury.)5.4 Syringe Injection
18、 DriveThe drive shall provide uni-form, continuous sample injections. Variation in drive injectionrate caused by mechanical irregularities of gears will causenoise. The adjustable drive shall be capable of injection from 6L/min to 0.06 L/min over a 6-min interval.5.5 RecorderA chart recorder with 10
19、-V full scale and10 000-V input or greater and having a chart speed of 0.2 to 1in./min (approximately 0.5 to 3 cm/min) is required. Anattenuator can be used for more sensitive recorders. Newerinstruments that display the results are acceptable in lieu of achart recorder.5.6 ThermocoupleA thermocoupl
20、e suitable for use at 500to 1400C, 250-mm long with readout is required. Type K,116-in. (1.6-mm) diameter, Type 316 stainless steel sheath issuitable.6. Reagents and Materials6.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall r
21、eagents conform to the specifications of the Committee onAnalytical Reagents of the American Chemical Society wheresuch specifications are available.5Other grades may be used,provided it is first ascertained that the reagent is of sufficientlyhigh purity to permit its use without lessening the accur
22、acy ofthe determination.6.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean Type II reagent gradewater conforming to Specification D 1193.6.3 Sensing TapeLead acetate impregnated paper of chro-matographic quality shall be used. (WarningLead is acumulative po
23、ison.)6.4 HydrogenAs no commercial grade of hydrogen has asulfur specification sufficiently low, each new source of supplymust be tested. A change in the zero base line of 5 % of fullscale from no flow to full flow indicates impure hydrogen.(WarningExtremely flammable gas under pressure. Hydro-gen i
24、s a flammable gas. Test all flow systems for leaks andpurge with inert gas before introducing hydrogen and afterremoving hydrogen. Keep all flow systems as small in volumeas practical and provide protective screening for containersother than sample flow lines. Dispose of exhaust gases in a5Reagent C
25、hemicals, American Chemical Society Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Annual Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand Nati
26、onal Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,MD.NOTEThe humidifier gas wash bottle is optional.FIG. 1 Hydrogenolysis Flow DiagramFIG. 2 Photorateometry H2S ReadoutD4045042fume hood or by vacuuming to a safe area. If gas cylinders areused handle carefully as rupture of the va
27、lve or cylinder isdangerous.)6.5 Reference Standards:6.5.1 2,2,4 Trimethyl Pentane (Isooctane)(WarningExtremely flammable.)6.5.1.1 ASTM Knock Test Reference Fuel6may be used asthe solvent. However, when this material is used, each new lotshall be tested for sulfur by this procedure because thespecif
28、ications are not rigorous enough for this application.NOTE 1Heptane or equivalent material may also be used but precisiondata is based on the use of isooctane.6.6 Acetic Acid SolutionMix glacial acetic acid 1 part byvolume into 19 parts water (see 6.2). (WarningCorrosive.)6.7 Di-n-Butyl Sulfide(CH3C
29、H2CH2CH2)2S) is used toprepare standards. Equivalent sulfur compound may be used ifcare is exercised to prevent more volatile compounds fromevaporating during preparation or use of standards.6.8 Helium or Nitrogen Purge Gas.(WarningCompressed gas under high pressure.)7. Preparation of Apparatus7.1 T
30、urn on the furnace with temperature controls at mini-mum. Gradually increase furnace control over a 3-h period toapproximately 1300C to minimize thermal shock. Reverse theprocedure when preparing for long-term storage. For shutdownat night and over weekends, reduce temperature to about 900Cbut do no
31、t turn off the furnace. Furnace and quartz tubing lifeare extended by not cooling to room temperature.7.2 Connect all tubing and fill prehumidifier outside thecabinet with water if this apparatus is being used, and finalhumidifier inside the cabinet with 5 % by volume acetic acidsolution. Purge with
32、 inert gas, then close valve. Check allconnections and repair any leaks that are found.(WarningOn instruments where electronics are in closeproximity with the flow systems, exercise care if leak checkingwith a soap solution. A suitable method is to block the line thatgoes to the final humidifier and
33、 observe the flow meter. If theflow drops to zero, the flow systems are adequately leak-free.)Set hydrogen flow at 200 mL/min, and allow temperature tostabilize. (WarningExtremely flammable gas under pres-sure.) Make final temperature adjustment to 1315 6 15C. Usea standard thermocouple to verify te
34、mperature by insertingthrough a septum with hydrogen flowing at the rate notedabove. Determine depth of insertion required, and always insertthe hypodermic tip to the 550C point (see 7.6). (WarningThe use of a humidifier gas wash bottle filled with approxi-mately 250 mL of water is a potential safet
35、y hazard ashydrogen pressure may build up inside the container. The userof this test method should take appropriate safety measures toprevent an accidental injury, if the humidifier gas wash bottleis used in the analysis.)7.3 Prepare the sample injection drive. Check to be suredesired injection rate
36、 is obtained at various settings. Verify thaterratic pulses of fast drive do not occur when the drive rangeis switched. Pulses of high sample flow above 15 L/min willcause carboning and spurious readings.7.4 Install sensing tape, and turn H2S readout analyzer on.7.5 Connect the recorder and adjust t
37、he zero to desiredposition with hydrogen flowing.7.6 Fill syringe with blank reference standard solution,typically isooctane, insert the needle through the septum to the550C temperature zone, and clamp to the syringe drive. Athigh temperature the hot needle may absorb sulfur and at lowertemperature
38、heavy compounds may not evaporate. Set thesyringe drive rate desired, normally 6 L/min, maximum with200 mL/min hydrogen flow. Drive rate may be increased forincreased sensitivity up to the point at which carbon is formed.(Hydrogen flow at 500 mL/min allows injection of 15 L/min;however, dibenzothiop
39、hene conversion will be low.)8. Calibration Standard8.1 Prepare a reference standard-solution or solutions ofstrength near that expected in the unknown. Measurements canbe made by weight or by volume for carrier liquid.8.2 Units of sulfur in milligrams per litre of sample arepreferred as this is ind
40、ependent of the density of the carrierliquid. The following equation is used to calculate the volumeof solvent required to dissolve a precise weight of sulfurcompound, of known composition and purity to prepare aliquid standard:z 5Sbc3 d 3 e 3 106D/a! or alternatively : (1)a 5Sbc3 d 3 e 3 106D/z! (2
41、)where:a = desired concentration of sulfur, mg/L, of the standardsolution of z millilitre of volume,b = molecular weight of sulfur: 32.06,c = molecular weight of the sulfur compound to be used toprepare the standard.d = mass of the sulfur compound used to prepare thestandard, g,e = purity of sulfur
42、compound expressed as a decimal, andz = millilitres of standard solution required to give thedesired concentration a.Example:Calculate the volume of sulfur free isooctane with volume ofsulfur compound necessary to dissolve 0.5013 g of 98 % byweight di-n-butyl sulfide to obtain a standard containing
43、1000mg/L of sulfur in a solution.a = 1000 mg/Lb = 32.06c = 146.29 di-n-butyl sulfide (CH3CH2CH2CH2)2Sd = 0.5013 ge = 0.98z =32.06/146.29 3 0.5013 3 0.98 3 10610005 107.66 mL6Available from Phillips Petroleum Co., P.O. Drawer O, Borger, TX 79071.D4045043Isooctane is added to bring the solution to a t
44、otal volume of107.66 mL. When results are to be reported in mass of parts permillion mg/kg, the conversion from milligrams per litre shouldbe done as the last step in the calculations.8.3 To prepare a sulfur standard with a sulfur concentrationof 1000 mg/L, as previously described, obtain a clean 12
45、5-mLglass container, a 100-mL flask, and a 20-mL graduated glasspipet. Rinse each thoroughly with 2,2,4-trimethyl pentane(isooctane). (WarningExtremely flammable.) Pour approxi-mately 90 mL of isooctane into the 100-mL flask. Weighapproximately 0.5 g of di-n-butyl sulfide directly into the flaskand
46、record the mass added, to 650 g. Add additionalisooctane to the flask to 100 mL. Transfer the mixture to the125-mL container and add isooctane equal to the difference ofz minus 100 mL. Keep containers closed as much as possible.Do not open containers of pure sulfur compound in the vicinityof sulfur
47、free stocks or low-level standards. Evaporation fromcontainers of pure sulfur compounds can contaminate othernearby liquids. This is particularly troublesome when workingbelow 1 mg/L near volatile sulfur compounds. Volumetricallydilute stock to prepare low-level standards.9. Calibration and Standard
48、ization9.1 With hydrogen flow at 200 mL/min, advance new tapeand note baseline. Adjust the offset up scale about 5 % to beclear of the recorder stops. Record the stable reading averagevalue as the zero sulfur reference and record as Rbin 11.1.There will be essentially no difference in reading with o
49、rwithout hydrogen flow and with or without blank injection, ifblank and hydrogen have no sulfur.9.2 Advance the tape and inject a reference material with asulfur concentration near that expected in the unknown. Afterabout 4 min injection time, adjust the recorder span forapproximately 90 % of scale. Record the average reading asRstdin 10.1.10. Procedure10.1 Advance the tape and inject the unknown sample. Aftera stable reading is obtained record this average value as Rsin11.1.10.2 Proceed with additional samples. Every 2 h, or asneeded
