1、Designation: D 6541 05Standard Specification forHFC-236fa, 1,1,1,3,3,3Hexafluoropropane, (CF3CH2CF3)1This standard is issued under the fixed designation D 6541; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revis
2、ion. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers the requirements for HFC-236fa as a fire-fighting medium.1.2 This specification does not address the
3、fire-fightingequipment or hardware that employs HFC-236fa or the condi-tions of employing such equipment (for example, hand-helds,fixed installations, and so forth).1.3 This specification does not address the storage ortransportation of HFC-236fa. Storage, handling, and transpor-tation issues are ad
4、dressed in Practice D 6427.1.4 The values stated in SI units are to be regarded asstandard. The values given in parentheses are for informationonly.1.5 The following safety hazards caveat pertains to the testmethods portion, Section 6.1, of this specification. This stan-dard does not purport to addr
5、ess all of the safety concerns, ifany, associated with its use. It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use. A specific warning statement is given in 4.3.2. Referenced
6、 Documents2.1 ASTM Standards:2D 6427 Practice for Handling, Transportation, and Storageof HFC-236fa, 1,1,1,3,3,3Hexafluoropropane(CF3CH2CF3)2.2 ISO Standards:3ISO 3363 Fluorinated Hydrocarbons for Industrial UseDetermination of Acidity-Titration MethodISO 3427 Gaseous Halogenated Hydrocarbons (Lique
7、fiedGases)Taking a SampleISO 5789 Fluorinated Hydrocarbons for Industrial UseDetermination of Nonvolatile Residue2.3 U.S. Government Standards:4Code of Federal Regulations (CFR) Title 49, Part 172.101Tables of Hazardous Materials and Special ProvisionsCode of Federal Regulations (CFR) Title 49, Part
8、 172Subpart D Marking Requirements of Packaging forTransportation2.4 American Society of Refrigeration Engineers Stan-dard:5ASHRAE Standard 34, Designation of Refrigerants3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 halogenated hydrocarbon (see Note 1)saturated hy-drocarbon
9、s in which one or more of the hydrogen atoms havebeen replaced by atoms of the halogen series (fluorine, chlo-rine, bromine, and iodine). It is convention to prefix thenumber with an abbreviation of the compound:CFC = chlorofluorocarbonHCFC = hydrochlorofluorocarbonHFC = hydrofluorocarbonFC = fluoro
10、carbonR = refrigerantNOTE 1The halogenated compound coding terminology system pro-vides a convenient means to reference halogenated hydrocarbons (seeASRE 34).3.1.1.1 By definition, the right-most digit of the numberingsystem is the number of fluorine atoms.3.1.1.2 The second digit from the right is
11、the number ofhydrogen atoms plus one (+1).3.1.1.3 The third digit from the right is one less (-1) than thenumber of carbon atoms in the compound (when this numberis zero, it is omitted from the number).3.1.1.4 Unaccounted for valance requirements are assumedto be chlorine atoms.3.1.1.5 When the comp
12、ound contains bromine or iodine, thesame rules apply, except the letter B for bromine or I for iodine1This specification is under the jurisdiction of ASTM Committee D26 onHalogenated Organic Solvents and Fire Extinguishing Agents and is the directresponsibility of Subcommittee D26.09 on Halogenated
13、Fire Extinguishants.Current edition approved June 1, 2005. Published July 2005. Originally approvedin 2000. Last previous edition approved in 2000 as D 654100.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of
14、ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute, 25 W. 43rd St., 4thFloor, New York, NY 10036.4Available from Superintendent of Documents, U.S. Government PrintingOffice, Washington, DC 20036.5Ava
15、ilable from American Society of Refrigeration Engineers, RefrigerationEngineering 65, 49 (1957).1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.follows the parent compound designated number, and thenumber of the atoms is placed after
16、 the letter.Example: CF3CH2CF35 R236fa 5 HFC236fa3.1.2 HFC-236fathe compound 1,1,1,3,3,3hexafluoro-propane; CF3CH2CF3.4. Material Requirements4.1 Type IMixtures of HFC-236fa and Nitrogen:4.1.1 The nitrogen (N2) partial pressure shall be such thatthe safe working pressure of the receiving vessel is n
17、otexceeded. To prevent excessive pressure, the fill density of theHFC-236fa/nitrogen within the container should not exceedthat needed to achieve complete filling of the container at themaximum expected storage temperature. For example, the U.S.DOT 4BA500 cylinder partial pressure shall not exceed 2
18、4.4bar at 21C (340 psig at 70F) for a 1153kg/m3(72 lb/ft3) filldensity. For this example, the safe working pressure of the4BA500 cylinder is not exceeded for temperatures below 54C(130F).4.1.2 HFC-236fa shall conform to the requirements pre-scribed in Table 1 when tested by the appropriate test meth
19、-od(s) listed in 6.1.4.1.3 When material analysis is required, by agreementbetween the purchaser and the supplier, the total pressure in theHFC-236fa container, partial pressure of the nitrogen, the filldensity of the HFC-236fa within the container, and the maxi-mum safe storage temperature shall be
20、 part of the materialanalysis (certification). The pressure shall be reported in bar(preferred) or pound-force per square inch gage (psig). The filldensity shall be reported in kilograms per cubic metre at 21C(preferred) or pounds per cubic foot at 70F. The maximumsafe storage temperature of the HFC
21、-236fa shall be reported indegrees Celsius (preferred) or in degrees Fahrenheit and shallconform to the applicable regulations for the HFC-236facontainer design and use.4.2 Type IIHFC-236fa shall conform to the requirementsof Type I, as listed in 4.1.1, and shall contain no more than 1.5% by volume
22、fixed gases in the vapor phase, expressed as airwhen tested by the appropriate test method(s) listed in Section6.1.4.3 By agreement between the purchaser and the supplier,analysis may be required and limits established for elements orcompounds not specified in Table 1.(WarningExposure toconcentratio
23、ns of HFC-236fa in excess of 15 % by volume inair during periods of elevated adrenaline could produce cardiacarrhythmia in some personnel.)4.4 Unless otherwise specified, Type I is assumed.5. Sampling5.1 Samples of HFC-236fa taken from the liquid phase,shall be taken from filled containers in accord
24、ance with themethod specified in ISO 3427. The sampling bottle shall becapable of safely resisting the vapor pressure of the sample atthe highest temperature that could be encountered.5.2 The HFC-236fa selected in accordance with 5.1 shall betested for quality conformance in accordance with Section
25、6.The presence of one or more defects shall be cause forrejection.6. Test Methods6.1 Purity:6.1.1 Determine the purity by gas chromatography in accor-dance with the technique described in 6.1.2.1-6.1.5.1 or an-other acceptable laboratory technique providing equivalentresults.6.1.2 ApparatusThe follo
26、wing special apparatus is re-quired to determine the percent HFC-236fa.6.1.2.1 Gas Chromatograph, equipped with a thermal con-ductivity detector (TCD) and an integrator, 1mV recorder, orother output device.6.1.2.2 Chromatographic Column, 6.0ft length by18 in.outside diameter (OD) stainless steel tub
27、ing, packed with 80 to100 mesh PORAPAK Q or equivalent (column is availableprepacked from any chromatographic supply vendor).6.1.2.3 Gas Sampling Valve, 1mL volume or a volumesufficient to achieve proper separation and peak area for thespecified column.6.1.3 Reagents:6.1.3.1 The carrier gas shall be
28、 a chromatographic grade ofhelium.6.1.3.2 The column packing shall be 80 to 100 meshPORAPAK Q or equivalent.6.1.4 Procedure:6.1.4.1 Install the column in the gas chromatograph and setthe oven temperature to 45C, injection port to 175C, detectorblock to 200C. The oven temperature is programmed to hol
29、dat 45C for 2 min, then rise 10C/min, to a maximum of 150C.6.1.4.2 Adjust the column helium flow to 20 mL/min.6.1.4.3 Adjust the detector voltage to the mid-range of thethermal conductivity detector (TCD) and allow the instrumentto equilibrate.6.1.4.4 Take a vapor (flashed liquid) sample from the li
30、quidphase (inverted cylinder). Flush the sample loop and valve forapproximately 30 s.6.1.4.5 Rotate the sample valve to transfer the sample intothe chromatograph and note the time.6.1.4.6 Close the sample cylinder valve.6.1.4.7 Allow the sample to elute for approximately 15 min,attenuating as necess
31、ary to make the peak height a convenientsize. Under proper instrument settings, air (N2,O2) shouldelute after about 0.4 min, and HFC-236fa should elute afterapproximately 8 min.6.1.5 Calculation:6.1.5.1 Calculate percent HFC-236fa as follows:% HFC2236fa 5 AH100!/ATwhere:AH= area of the HFC-236fa pea
32、k (peak area 3 attenua-tion), andTABLE 1 RequirementsProperty RequirementHFC-236fa purity, %, mol/mol, min 99 (exclusive of any N2present)Acidity, ppm by mass, as HCl, max 1.0Water content, ppm by mass, max 10Nonvolatile residue, % by weight, max 0.03Suspended matter or sediment none visibleD6541052
33、AT= sum of all relevant peak areas excluding the nitrogen(air) peak (peak area 3 attenuation).Percent HFC-236fa below that specified in Table 1 shallconstitute failure by this test method.6.1.5.2 Calculate the percent nitrogen (air) as follows:%N2air!5AN100!/AT1 AN!where:AN= area of the nitrogen (ai
34、r) peak, andAT= sum of all the relevant peak areas including thenitrogen (air) peak.It is useful to calculate the percent nitrogen (air) to judge asafe fill density. This is the amount of nitrogen (air) in theliquid phase.6.2 AcidityVaporize a large sample in the presence ofdistilled water. Determin
35、e the acidity of the solution by theappropriate method specified in ISO 3363, titration in accor-dance with 6.2.1.3 and 6.3, a pH indicator, or another accept-able laboratory technique providing equivalent results.6.2.1 Sodium Hydroxide Titration:6.2.1.1 Reagents:(1) Sodium Hydroxide, 0.01 N solutio
36、n, standardized againstreagent grade potassium acid phthalate.(2) Methyl Red Indicator, 0.1 % solution.6.2.1.2 ProcedurePlace 50 mL distilled water-crushed ice(made from distilled water) slurry in a 250mL Erlenmeyerflask. Sparge 50 g of the HFC-236fa into the slurry. Looselystopper the flask and swi
37、rl the flask gently from time to timeuntil the ice is completely melted. Add 1 drop of methyl redindicator, swirl, and if a reddish color remains, titrate to ayellow end point with 0.01 N sodium hydroxide solution. Runa crushed ice-distilled water blank (no HFC-236fa) along withthe sample.6.2.1.3 Ca
38、lculation Calculate parts per million acid ha-lides, as HCl, as follows:acid halides, ppm 5AB!3 N NaOH 3 0.03645 3 106weight of samplewhere:A = NaOH for sample, mL,B = NaOH for blank, mL,N = normality of the NaOH solution,NaOH = sodium hydroxide, and0.03645 3 106= factor to express result as ppm HCl
39、(hydrogen chloride).Acid halides in excess of that specified in Table 1 shallconstitute failure by this test method.6.3 Water Content Test HFC-236fa for water content. Thestandard test method shall be by the Karl Fischer method. Theanalysis may be conducted by the phosphorous pentoxide testmethod, i
40、nfrared absorption, electronic moisture analysis, pi-ezoelectric analyzer, or another acceptable laboratory tech-nique. Water content greater than specified in Table 1 shallconstitute failure by this test method.6.4 Nonvolatile ResidueDetermine the nonvolatile resi-due in accordance with the method
41、specified in ISO 5789 oranother accepted laboratory technique providing equivalentresults. Determine suspended matter or sediment (see 6.6)while performing this analysis.6.5 Fixed Gases in the Vapor PhaseTest HFC-236fa forthe presence of air in the vapor phase by gas chromatography,or another accept
42、ed laboratory technique providing equivalentresults.6.5.1 Gas ChromatographyHFC-236fa may be tested forthe concentration of air in the vapor phase by gas chromatog-raphy. A concentration of air in excess of 1.5 % by volumeshall constitute failure by this test method.6.5.2 Procedure I Follow the proc
43、edure as outlined in6.1.1, except the sample is taken from the vapor space of thecontainer. This will be an area, volume percent result. Air (N2,O2) will elute after about 0.4 min.6.5.3 Procedure II:6.5.3.1 ApparatusThe following special apparatus is re-quired to determine the percent fixed gases in
44、 HFC-236fa:(1) Gas Chromatograph, equipped with a thermal conduc-tivity detector (TCD) and an integrator, 1mV recorder, orother output device.(2) Chromatographic Column, 9m length by 3.175mmoutside diameter (29.5ft by18 in.) stainless steel tubing,packed with 30 to 60 mesh 133 molecular sieve. (Colu
45、mn isavailable prepacked from any chromatographic supply vendor.)(3) Gas Sampling Valve, 1mLvolume or a volume sufficientto achieve proper separation and peak area for the specifiedcolumn.6.5.4 Reagents:6.5.4.1 Carrier Gas, shall be a chromatographic grade ofhelium.6.5.4.2 Column Packing, shall be 3
46、0 to 60 mesh 133molecular sieve.6.5.4.3 Calibration Gas0.8 to 2 % N2and 0.2 to 1 % O2in helium. Available from specialty gas suppliers.6.5.5 Procedure:6.5.5.1 Install the column in the gas chromatograph and setthe oven temperature to 100C, the injection port to 200C, andthe detector block to 200C. T
47、he oven temperature is pro-grammed to hold at 100C for 11 min, then rise to 35C/min,to a maximum of 190C, and hold for 30 min.6.5.5.2 Adjust the column helium flow to 15 mL/min.6.5.5.3 Adjust the detector voltage to the mid-range of thethermal conductivity detector (TCD) and allow the instrumentto e
48、qulibrate.6.5.5.4 Take the sample from the vapor phase. Flush thesample loop and valve for approximately 30 s at a flow rate of20 mL/min.6.5.5.5 Rotate the sample valve to transfer the sample intothe chromatograph and note the time.6.5.5.6 Close the sample cylinder valve.6.5.5.7 Allow the sample to
49、elute for approximately 42 min,attenuating as necessary to make the peak height a convenientsize. Under proper instrument settings, the oxygen will elute atapproximately 2 min and nitrogen will elute at approximately3 min.6.5.6 Calculation:6.5.6.1 Calibration Calibration factors are determined byanalyzing the standard gas in accordance with 6.5.5.1 andcalculating as follows:FN5 %N2in standard gas/ AND6541053FO5 %O2in standard gas/ AOwhere:AN= area of nitrogen peak,AO= area of oxygen peak,FN= nitrogen factor, andFO= oxygen
