1、ASTM D5020 87 E 0759530 0038637 T W(-di)Designation:D 5020-89 AMERICAN SOCIETY FOR TESTINO AND MATERIALS 1916 Race SI.,Philadelphia.Pa.19103 Reprinted Irom lhe Annual Book d ASTM SUndardr.COpyrigM ASTM If noi listed In the current combined index,wul r p p e u in thr mxl dlh.Standard Test Method for
2、Chlorofluorocarbon Activity of Activated Carbon This standard is issued under the fixed designation D 5020;the number immediately following the designation indicates the year of onginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the yeat of last r
3、eapproval.A superscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope 1.1 This test method covers the determination of the CFC(chlorofluorocarbon)activity of new or reactivated activated carbon.CFC activity is defined as the ratio,in percent,of the weight of t
4、est adsorbate,I,2-dichlorotetrafluoroethane(CFC-1 14),adsorbed after the sample of activated carbon is saturated under conditions described in this test method,to the initial weight of the sample.1.2 Test Method D 3467 is similar to this test method,but employs carbon tetrachloride as the test adsor
5、bate.Sosa and Underhill:with measurements from eighteen activated carbons,found that a linear regression of the activity determined by carbon tetrachloride(as the y-axis)versus the CFC activity determined using CFC-I 14(as the x-axis)can be expressed by the equation:y=0.985 f 0.10 with a correlation
6、 coefficient of 0.997.Thus,although the results obtained with CFC-114 are highly predictive of the activity determined using carbon tetrachloride,these activities are not generally equivalent,and the test adsorbate used for the procedure should be stated.Jonas and Sosa and Underhil12 predicted this
7、lack of equivalence from differences in the vapor pressure,density of the liquid phases,and polanza-bility of the test adsorbates.1.3 This standard may involve hazardous materials,oper-ations,und equipment.This standurd does not purport io address all o f the safety problems associated with its use.
8、It is tite responsibility o f the user o f this standard to establish appropriate sufety and health practices and determine the upplicability o f regulatory limitations prior to use.For a specific hazard statement,see Section 7.2.Referenced Documents 2.1 ASTM Standards:D 2652 Definitions of Terms Re
9、lating to Activated D 2867 Test Method for Moisture in Activated Carbon3 D 3467 Test Method for Carbon Tetrachloride Activity of D 3447 Test Method for Purity of Trichlorotrifluoro-E 300 Practice for Sampling Industrial Chemicals4 Carbon3 Activated Carbon3 ethane4-This test method is under the juris
10、diction of ASTM Committee D-28 on Activated Carbon and is the direct responsibiliiy of Subcommittee D28.04 on G a s Phase Evaluation Tcsts.Currenl edition approved Lkc.29,1989.Published February 1990.Sosa,A.,and Underhill,D.,“Substitutes for Carbon Tetrachloride in the Standard ASTM Mcthod for Activ
11、ity of Activated Carbon,”Journal ofllie Air Polliilioti Cunlrol Associariun,Vol 34,1984,pp.1215-1217.Atiiiiial Bouk ofASTM Standards,Vol 15.01.Anniid Book ufASThi Statidards,Vol 15.05.3.Terminology fined in Definitions D 2652.4.Summary of Test Method 4.1 CFC activity is determined by flowing the tes
12、t adsorb-ate,CFC-I 14,under specified conditions,through a sample of activated carbon of known weight,until the activated carbon is saturated;then,the weight of retained adsorbate is determined.The adsorbed CFC is expressed as a weight percentage of the dried activated carbon and is termed the CFC a
13、ctivity.3.1 Definitions-Terms relating to this standard are de-5.Significance and Use 5.1 CFC activity measured by this test method is basically a measure of the micropore volume of the activated carbon sample.This test method is therefore a means of determining the degree of activation,and hence is
14、 a useful means of quality control for activated carbons.6.Apparatus 6.1 Balance,capable of weighing to within k 1 mg.6.2 Suitable Flow Control Device.6.3 Adsorption Tube,as shown in Fig.1.6.4 Thermostatted Water Bath,capable of maintaining sample tube at a temperature of 25 I:1C.7.Reagents and Mate
15、riais 7.1 CFC-ZZ4,95%by weight minimum content of 1,2-dichlorotetrafluoroethane,99.7%by weight minimum con-tent of 1,2-dichlorotetrafluoroethane plus 1,I-dichlorotetra-fluoroethane?Test Method D3447 may be modified to determine the purity of CFC-114.8.Hazards 8.1 Warning:Operate the test equipment i
16、n a well-designed fume hood capable of exhausting any vapors released.The 1988 TLV for CFC-114 is 1000 ppm TWA(Time Weighted Average)for an eight hour exposure.Contact with liquid CFC-I 14 may cause frostbite.Conform conditions for stack release of CFC-114 to the regulations of the U.S.Environmental Protection Agency,9.Sampling carbon.9.1 See Practice E 300 for guidance in sampling activated CFC-I 14 available from Scientific Gas Products,Plainfield,NJ,Scott Specialty Gases,Plumsfeadville,PA,and