1、Designation: D 5757 00 (Reapproved 2006)Standard Test Method forDetermination of Attrition and Abrasion of PowderedCatalysts by Air Jets1This standard is issued under the fixed designation D 5757; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 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. Scope1.1 This test method covers the determination of the relativeattrition characteristics of powde
3、red catalysts by means of airjet attrition. It is applicable to spherically or irregularly shapedparticles which range in size between 10 and 180 m, haveskeletal densities between 2.4 and 3.0 g/cm3(2400 and3000 kg/m3) (see IEEE/ASTM SI-10) and are insoluble inwater. Particles less than 20 m are cons
4、idered fines.1.2 This standard does not purport to address all of thesafety 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.
5、 Referenced Documents2.1 ASTM Standards:2E 177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE 456 Terminology Relating to Quality and StatisticsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodIEEE/ASTM SI-10 Standard for Use of
6、the InternationalSystem of Units (SI): The Modern Metric System23. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 Air Jet Index (AJI)a unitless value numericallyequal to the percent attrition loss at 5 h.4. Summary of Test Method4.1 A sample of dried powder is humidified and att
7、rited bymeans of three high velocity jets of humidified air. The finesare continuously removed from the attrition zone by elutriationinto a fines collection assembly.4.2 The AJI is calculated from the elutriated fines to give arelative estimate of the attrition resistance of the powderedcatalyst as
8、may be observed in commercial use.5. Significance and Use5.1 This test method is intended to provide informationconcerning the ability of a powdered catalyst to resist particlesize reduction during use in a fluidized environment.5.2 This test method is suitable for specification acceptance,manufactu
9、ring control, and research and development pur-poses.6. Apparatus6.1 The air jet attrition system consists of the following:6.1.1 Attrition Tube, a stainless steel tube 710-mm long witha 35-mm inside diameter.NOTE 1NPS 114-in. pipe, Schedule 40 has the appropriate insidediameter.6.1.2 Three 2-mm Lon
10、g Drilled Sapphire Square EdgedNozzles, precision drilled 0.381 6 0.005 mm in diameter. Theyare mounted equidistant from each other, 10 mm from centerand flush with the top surface in a circular orifice plate 6.4-mmthick. The plate is designed to be attached to the bottom of thevertical attrition tu
11、be within an air delivery manifold.6.1.3 Settling Chamber, a 300-mm long cylinder with a110-mm inside diameter and with conical ends reducing to30-mm inside diameter. The upper cone is approximately100-mm long and the lower cone is approximately 230-mmlong. The chamber is mounted to the top of the a
12、ttrition tube.6.1.4 Fines Collection Assembly, made up of a 250-mLfiltering flask, an extraction thimble connected to the side armsof the flask, and a 200 by 13-mm diameter metal tubing bent toan angle of 125 connecting the top of the flask to the top of thesettling chamber.NOTE 2The flask may be el
13、iminated and the thimble connecteddirectly to the tubing if the attrition is expected to be low enough to avoidclogging the thimble and creating a backpressure in the settling chamber.1This test method is under the jurisdiction of ASTM Committee D32 onCatalysts and is the direct responsibility of Su
14、bcommittee D32.02 on Physical-Mechanical Properties.Current edition approved Oct. 1, 2006. Published November 2006. Originallyapproved in 1995. Last previous edition approved in 2000 as D 575700.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at
15、serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.1.5 Rubber Couplers and Seals, appropriately size
16、d toensure tight and leak free connections of the system.6.2 Air Supply Source, controlled and capable of maintain-ing an air flow rate of 10.00 L/min stable to 0.05 L/min at apressure up to 200 kPa. The air must be at a relative humidityof 30 to 40 % to minimize electrostatic effects.NOTE 3The air
17、may be bubbled through a 0.25-m column ofdeionized water at ambient temperature to obtain the required humidity.6.3 Diaphragm-Type Test Meter (dry test meter) or Liquid-Sealed Rotating Drum Meter (wet test meter), minimumcapacity of 30 L/min and maximum scale subdivision of 0.1 L.6.4 Balance, 400-g
18、capacity open pan with 0.01-g sensitiv-ity.6.5 Desiccator, with a desiccant grade molecular sieve suchas 4A.6.6 Muffle Furnace.6.7 Relative Humidity Gage.7. Sampling7.1 Obtain a representative sample of approximately 65 g ofmaterial from larger composites by riffling or splitting with theaim of obta
19、ining a sample that represents the size distributionof the larger composite.7.2 Gently screen the sample through a No. 80 (180 m)ASTM sieve to remove any particles larger than 180 m.7.3 The step in 7.3.1 is followed for all samples except freshFCC catalysts for proper equilibration at 35 % humidity
20、toavoid absorption of water during the test.7.3.1 Transfer the presieved sample to a shallow wide dishand place in a humidifier over a saturated calcium chloridesolution for 16 h.7.4 The steps in 7.4.1-7.4.4 are followed for fresh FCCcatalysts to ensure a proper moisture level that will not changedu
21、ring the test.7.4.1 Transfer the presieved sample to a shallow dish anddryitfor1hinamufflefurnace preheated to 565C.7.4.2 Cool the sample to room temperature in a desiccator.7.4.3 Mix 45 g of the dried and cooled material thoroughlywith5gofdemineralized water ensuring that the water is welldispersed
22、 and that there are no lumps of material present.7.4.4 Allow the sample to stand over a saturated calciumchloride solution in a humidifier for 1 h.8. Preparation of Apparatus8.1 Thoroughly clean any residual material from the appa-ratus by tapping it loose and blowing or vacuuming the dust.Reassembl
23、e the system except for the fines collection assem-bly.8.2 Turn on the air supply and adjust the relative humidityof the air exiting the settling chamber to a range of 30 to 40 %.8.3 Connect the inlet of the wet test gas meter to the top ofthe settling chamber and adjust the humidified air flow to 1
24、0.006 0.05 L/min at standard temperature and pressure (STP)(273.15 K and 101.325 kPa). The back pressure should be inthe range of 130 to 180 kPa; if it is not, check that the air jetnozzles are clean and within specifications and that there are noleaks in the apparatus connections.8.4 Prepare two fi
25、nes collection assemblies and conditionthe thimbles by installing them on the apparatus in successionand passing the humidified air through the apparatus for 30 mineach.9. Procedure9.1 Weigh the first conditioned fines collection assembly tothe nearest 0.01 g and record its mass.9.2 With the air flo
26、wing at the prescribed 10.00 L/min andthe fines collection assembly off, charge 50 g of waterequilibrated sample to the apparatus through the top of thesettling chamber, quickly secure the first fines collectionassembly to the apparatus and start the timekeeping.9.3 Weigh the second conditioned fine
27、s collection assemblyto the nearest 0.01 g and record its mass.9.4 After exactly 1 h from the start, replace the first finescollection assembly with the second one. Weigh and record themass of the first fines collection assembly.9.5 After exactly 5 h from the start, remove the finescollection assemb
28、ly, weigh it, and record its mass.9.6 Turn off the apparatus and disassemble.9.7 Recover the sample from the attrition tube and settlingchamber and weigh to the nearest 0.01 g.9.8 Clean the apparatus.10. Calculations10.1 Calculate the percent fines lost in the first hour asfollows:fines loss, % 5 m1
29、2 m0!/ms3 100 (1)where:m0= mass of the first empty fines collection assembly atthe start of the test, g,m1= mass of the first fines collection assembly at 1 h, g,andms= mass of the sample charged to apparatus (nominally50 g).10.2 Calculate the percent fines lost from attrition at the fifthhour as fo
30、llows:attrition loss, % 5 m12 m01 m52 m80!/ms3 100 (2)where:m80= mass of the second empty fines collection assembly,g, andm5= mass of the second fines collection assembly at 5 h,g.10.3 Calculate the percent sample recovery after the test asfollows:recovery, % 5 m11 m51 mr2 m02 m80!/ms3 100 (3)where:
31、mr= mass of the sample recovered from the attrition tubeand the settling chamber.11. Report11.1 Report the following information:11.1.1 The AJI.11.1.2 The first hour fines loss as percent.11.1.3 The recovery as percent.D 5757 00 (2006)212. Precision and Bias12.1 Test ProgramAn interlaboratory study
32、was con-ducted in which the named property was measured in fourseparate test materials in four to seven separate laboratories.Practice E 691, modified for nonuniform data sets, was fol-lowed for the data reduction. Analysis details are in theresearch report.12.2 PrecisionPairs of test results obtain
33、ed by a proce-dure similar to that described in the study are expected to differin absolute value by less than 2.772 S, where 2.772 S is the95 % probability interval limit on the difference between twotest results, and S is the appropriate estimate of standarddeviation. Definitions and usage are giv
34、en in Practices E 456and E 177, respectively. See Table 1.12.3 BiasThe procedure in this test method for measuringattrition has no known bias because the value of the attritionloss is defined only in terms of this test method.13. Keywords13.1 abrasion; air jet; attrition; fines; powdered catalystsAS
35、TM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are e
36、ntirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards
37、and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee
38、 on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or
39、 at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).TABLE 1 Repeatability and ReproducibilityTest ResultAJI(consensus mean)95 % Repeatability Interval(within laboratory)95 % Reproducibility Interval(between laboratories)2.530 0.226 (8.95 % of mean) 0.907 (35.9 % of mean)4.209 0.279 (6.64 % of mean) 1.939 (46.1 % of mean)20.353 1.121 (5.51 % of mean) 11.370 (55.9 % of mean)39.945 1.414 (3.54 % of mean) 12.029 (30.1 % of mean)D 5757 00 (2006)3
