1、Designation: D7964/D7964M 14Standard Test Method forDetermining Activity of Fluid Catalytic Cracking (FCC)Catalysts in a Fluidized Bed1This standard is issued under the fixed designation D7964/D7964M; the number immediately following the designation indicates theyear of original adoption or, in the
2、case of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers determining the activity andcoke selectivity of either equilibri
3、um or laboratory deactivatedfluid catalytic cracking (FCC) catalysts. The activity is evalu-ated on the basis of mass percent conversion of gas oil feed ina fluidized bed reactor. The coke yield is defined as the mass ofcarbon laid down on the catalyst, also expressed as a percent ofthe gas oil feed
4、. The scope of the round robin will be limitedto the determination of activity and coke.All other analyses arethus beyond this scope and should be noted as “optional.”1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach syste
5、m may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is therespo
6、nsibility 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:2D2887 Test Method for Boiling Range Distribution of Pe-troleum Fractions by Gas Chromatograp
7、hyD4463 Guide for Metals Free Steam Deactivation of FreshFluid Cracking CatalystsE105 Practice for Probability Sampling of MaterialsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Metho
8、d3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 activitya measure of the rate of a specific catalyticreaction, calculated in the present case by dividing conversionby the difference of 100 minus conversion.3.1.2 catalyst/oil (C/O) ratiothe mass of catalyst used inthe test div
9、ided by the mass of feed fed to the reactor.3.1.3 cokemass of carbon laid down on the catalyst duringthe FCC reaction times 1.083.3.1.4 conversionthe starting mass of reactant feed minusthe mass of the liquid product that boils above 221C 430F;this delta is then reported as a percentage of the start
10、ing massof feed.3.1.5 delivery timethis is the time, in seconds, duringwhich feed is introduced to the reactor.3.1.6 FCCfluid catalytic cracking.3.1.7 gasolineC5compounds through compounds boilingat 221C 430F.3.1.8 HCOthe heavy cycle oil product, which is defined tohave a minimum boiling point of 34
11、3C 650F.3.1.9 LCOthe light cycle oil product, which is defined tohave a boiling point range of 221 to 343C 430 to 650F.3.1.10 liquid productall products formed in the catalyticreaction that can be condensed in the chiller bath afterward,usually a combination of gasoline, LCO, and HCO, but cancontain
12、 a trace of C4and C4minus compounds.3.1.11 normalized product yieldthe result obtained wheneach product yield has been corrected for non-perfect massbalances.3.1.11.1 DiscussionFor a run to be judged acceptable, thetotal recovery, mass % of feed, should be in the range of 96 to102 % prior to normali
13、zation. If the recovery is outside thisrange the test data should be discarded.3.1.12 product yieldone hundred times the mass of aspecific product divided by the mass of feed used in the test.3.1.13 selectivitysame as yield. Selectivity generally re-fers to how much of a particular product, such as
14、coke, isformed during a chemical reaction; selectivity is related to, but1This test method is under the jurisdiction of ASTM Committee D32 onCatalysts and is the direct responsibility of Subcommittee D32.04 on CatalyticProperties.Current edition approved Nov. 1, 2014. Published January 2015. DOI: 10
15、.1520/D7964-14.2For referenced ASTM standards, visit the ASTM website, 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.Copyright ASTM International, 100 Barr Harbor
16、Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1different from, conversion, which is the total amount of allproducts formed during the reaction.4. Summary of Test Method4.1 A sample of FCC catalyst is contacted with gas oil in afluidized bed reactor using a specified reaction tem
17、perature, aspecified mass of catalyst and oil, and specified oil feed rate.Reaction products (liquid product, gas, and coke on catalyst)are analyzed. Conversion, coke, and individual product yieldsare calculated for each experiment.4.2 Following analysis of the products, the total recovery(that is,
18、mass balance) of the feed as converted and uncon-verted products is determined. If the recovery is less than 96 %or greater than 102 %, then the test is rejected as unsatisfactory(an outlier).4.3 For each catalyst tested, a normalized conversion oractivity and a coke mass are determined.5. Significa
19、nce and Use5.1 The fluidized bed test provides data to assess the relativeperformances of FCC catalysts. Because results are affected bycatalyst pretreatment, feedstock characteristics, and operatingparameters, this test method is written specifically to addressthe accuracy and precision when a comm
20、on catalyst and oil aretested under the same conditions but at different sites, usingKayser Technologies Advanced Catalytic Evaluation (ACE)unit.3,4Analytical procedures may vary among the sites.However, significant variations are not expected.NOTE 1ASTM International takes no position respecting th
21、e validityof any patent rights asserted in connection with any item mentioned in thisstandard. Users of this standard are expressly advised that determinationof the validity of any such patent rights, and the risk of infringement ofsuch rights, are entirely their own responsibility.5.2 The standard
22、reaction temperature for purposes of theaccuracy and precision statement is 532C 990F. Otherreaction temperatures can be used in practice; however, yielddata developed at temperatures other than 532C 990F willnot be the same. Also, test precision may be different at otherreaction temperatures.6. App
23、aratus6.1 The fluidized bed reactor of this test method is shown inFig. 1. The full ACE apparatus also includes a feed deliverysystem and both a gas and a liquid collection system. In atypical gas collection system, water is displaced by thecollected gas and the volume of displaced water provides aq
24、uantitative measurement of the amount of gas collected.Committee D32 can only suggest and will not recommend norcertify any specific vendor. However, significant variationsfrom the test apparatus of this method most likely will result insignificantly different activity and selectivity data from iden
25、ti-cal catalyst samples.3The fluidized bed reactor described herein is covered by US Patent 6,069,012.Interested parties are invited to identify an alternative(s) to this patented reactorsystem.Alternative(s) should be submitted to theASTM International Headquarters.Your comments will receive carefu
26、l consideration at a meeting of the responsibletechnical committee,1which you may attend.4Trademarked, ACE Technology.FIG. 1 Fluidized Bed ReactorD7964/D7964M 1426.2 Chromatographic Equipment:6.2.1 Liquid product analyses should be performed usingTest Method D2887 on a gas chromatograph (GC) equippe
27、dwith a flame ionization detector.6.2.2 Gas product analyses may be accomplished in twoparts. First, a GC equipped with a thermal conductivitydetector is needed for quantitative identification of H2and N2.H2S can optionally be detected, but will not be quantitative inunits that collect gas by water
28、displacement. The second part ofthe analysis requires a GC equipped with either FID or TCD,for the separation and quantitative identification of hydrocar-bon species. Typically, the following compounds are individu-ally quantified: methane, ethane, ethylene, propane, propylene,n-butane, iso-butane,
29、1-butene and iso-butene, cis-2-butene,trans-2-butene, iso-pentane, n-pentane, and the unsaturated C5isomers (C5olefins). For purposes of this test method andround robin the higher boiling gaseous compounds will belumped into a C6+fraction. If C5olefins are not separatelyidentified, then they are inc
30、luded with the C6+lump as well.The mass of the C5s and the C6+group are mathematicallyadded to the gasoline liquid fraction.6.3 Carbon analysis of a representative sample of the spentcatalyst (that is, after the cracking reaction has been com-pleted) may be accomplished using a commercially availabl
31、ecarbon analyzer if the ACE unit being used does not havecatalyst regeneration capability. If theACE is a model that doeshave regeneration capability, then the carbon on catalyst isback calculated from the CO2evolved in the flue gas during theregeneration cycle.7. Sampling7.1 A sampling procedure is
32、 needed. Practice E105 isappropriate.8. Sample Preparation8.1 Equilibrium CatalystsDry samples and remove cokeby heating a shallow (less than 10 mm thick) bed of catalyst ina porcelain crucible at 590 6 20C 1094 6 36F for a lengthof time sufficient to remove any coke. This typically requiresapproxim
33、ately 3 h. Sufficient air should be available in thefurnace to burn the sample free of coke. Insufficient cokeremoval is indicated by a difference in color of the top andbottom layers. The hot crucible is cooled in a desiccator toprevent moisture pickup. Only equilibrium catalyst will beused in the
34、precision and bias statement of this test method.NOTE 2Heavily coked samples may be damaged by sintering ordeactivation if oxidation is allowed to occur too rapidly, leading toartificially low catalytic activity and surface area.8.2 Fresh CatalystsFresh catalyst samples should besteam treated prior
35、to ACE testing. Steaming procedures suchas those specified in Guide D4463 may be used. However,specific conditions (temperature, partial pressure of steam, andtime) should be chosen such that the steamed catalyst proper-ties (activity, zeolite and matrix surface areas, and unit cellsize) approximate
36、 those found in equilibrium FCC catalysts ofthe same type.9. Procedure9.1 Reactor Preparation:9.1.1 The oil feed line on the ACE unit is meant to bechanged with some regularity. Whenever the oil feed linepressure exceeds 1.5 psig, the feed line should be changed. Forpurpose of this round robin, inst
37、all a feed line that yields a1.125 in. injector height. Injector height is defined as thedistance from the lowest point of the conical reactor bottom tothe bottom end of the feed injector.9.1.2 The drier tube and humidifier should be serviced asdescribed in the ACE Operating Manual.9.1.3 The ACE CO2
38、analyzer should be calibrated as de-scribed in the ACE Operating Manual.9.2 Preparation of Syringe and Liquid Product Receiver:9.2.1 Preheat the gas oil feedstock to 170 6 5C 338 69F, at which temperature a typical Gulf Coast gas oil willflow easily into the syringe and can be accurately delivered t
39、othe reactor. Set the oil feed pump to deliver feed at theprescribed rate for this testing. Calibration of the feed rate is amanual process consisting of changing the speed setting on thepump and performing a feed test. The oil feed line is opened sothat oil can be delivered into a tared beaker. The
40、 amount perminute is recorded and the test repeated until the oil masscollected is on target.NOTE 3If heavier feedstocks are used, the measured rate may beinconsistent. The syringe temperature can be increased to 220 6 5C 4286 9F as long as this does not exceed the initial boiling point of the oil.9
41、.2.2 A small plug of glass wool should be placed in theoutlet of the receiver to reduce the carryover of C5+aerosolinto the gas collection vessel. Obtain the initial mass of theliquid product receiver(s) including the glass wool.9.2.3 Install receiver(s) and connect the gas line to the gascollection
42、 system. Open the gas vent valve to prevent prema-ture collection of purge gas.9.2.4 Prepare ethylene glycol bath(s) for the receiver(s) ifneeded. Immerse the receiver(s) to the level of the gas outletline(s). Maintain the bath temperature at 15C 10F.9.2.5 Pressure TestPressurize the reactor to 20 k
43、Pa 150mm Hg nitrogen and close the gas vent and nitrogen supplyvalves. Watch the pressure gages for 2 min to determine if anysignificant leaks occur. If no leaks are apparent using thecriteria specified in the ACE Operating Manual, then open thegas vent valve carefully to release pressure.9.3 Perfor
44、ming the Run:9.3.1 Set up the run conditions in the ACE control interface.Up to 6 runs can be programmed to run automatically on theACE unit.9.3.2 Once the reaction is complete and the gas has beencollected, record the volume of displaced water (VB), the gastemperature (TR), and atmospheric pressure
45、 (PR). Typically thisis done through the ACE control interface. After being mixed,the collected gases may then be analyzed immediately bysyringe sampling or by forcing from the gas collection systeminto a gas sampling loop or a sealable gas sample bag forstorage and later analysis.9.3.3 If using a M
46、odel R or R+ unit, then the carbon massdetermined by IR must be recorded for later analysis ofproducts. If using an ACE unit that is not equipped withD7964/D7964M 143catalyst regeneration capability (Model AP or P), then alterna-tively the catalyst can be removed from the reactor for carbonanalysis
47、as described in 9.4.8.9.4 Analyses of Products:9.4.1 Remove the liquid product receiver(s) and immedi-ately cork the top. After removing the liquid receiver from thebath, the outside is rinsed with water and then with acetone. Itis allowed to dry on a rack for 20 min. The contents will warmup a bit
48、during this time so the cork remains in the receiveruntil final weighing.9.4.2 Collect the liquid holdup in the reactor exit line andaround the reactor-receiver joint with a tared cotton wool swabor other suitable material. Determine the mass of this liquidand record (WQ). Experience indicates this
49、liquid material ispredominantly unconverted feed.9.4.3 The receiver is weighed for mass balance purposesand the mass recorded.9.4.4 The vial containing the liquid product is removed andplaced in the autoinjector tray of the simulated distillationanalyzer, typically an Agilent gas chromatograph equippedwith appropriate software for boiling point analysis.9.4.5 Using Test Method D2887, simulated distillation,determine the mass percentage of the liquid products boiling inthe ranges of gasoline, IBP to 221C 430F and LCO
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