1、Designation: D5154 10Standard Test Method forDetermining Activity and Selectivity of Fluid CatalyticCracking (FCC) Catalysts by Microactivity Test1This standard is issued under the fixed designation D5154; the number immediately following the designation indicates the year oforiginal adoption or, in
2、 the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers determining the activity andselectivity of either equilibri
3、um or laboratory deactivated fluidcatalytic cracking (FCC) catalysts. The activity is evaluated onthe basis of mass percent conversion of gas oil in a microac-tivity unit. The selectivities are evaluated on the basis of masspercent yields of specifically defined products resulting fromthe catalytic
4、cracking of gas oil.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.2.1 ExceptionSI units have been retained in some of thefigures.
5、1.3 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. Referenced D
6、ocuments2.1 ASTM Standards:2D2887 Test Method for Boiling Range Distribution ofPetroleum Fractions by Gas ChromatographyD3907 Test Method for Testing Fluid Catalytic Cracking(FCC) Catalysts by Microactivity TestD4463 Guide for Metals Free Steam Deactivation of FreshFluid Cracking CatalystsE105 Pract
7、ice for Probability Sampling of MaterialsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE456 Terminology Relating to Quality and StatisticsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3. Terminology3.1 Definitions of Terms
8、Specific to This Standard:3.1.1 activitycalculated as conversion divided by thedifference of 100 minus conversion.3.1.2 ASTM reference catalystsa set of equilibrium FCCcatalysts within the useful range of this test method is used toimprove the reproducibility of test results between differentlaborat
9、ories. Each catalyst has a consensus mean conversionvalue assigned to it by Committee D32. Samples of the ASTMreference catalysts can be obtained through NIST.3.1.3 ASTM standard feeda specific batch of gas oil that isused as feedstock in the described test method.33.1.4 catalyst/oil (C/O) ratiothe
10、mass of catalyst used inthe test divided by the mass of feed fed to the reactor. Inpractice, the mass of catalyst is usually maintained at aconstant value and the total mass of feed is varied.3.1.5 contact timecalculated as 3600/(WHSV C/O). Thisis the delivery time, in seconds, during which feed is
11、intro-duced to the reactor.3.1.6 HCOthe heavy cycle oil product defined to have aminimum boiling point of 650F (343C).3.1.7 LCOthe light cycle oil product defined to have aboiling point range of 421 to 650F (216 to 343C).3.1.8 measured conversioncalculated as the differencebetween the mass of feed u
12、sed and the mass of unconvertedmaterial divided by the mass of feed used times 100 %. Theunconverted material is defined as all liquid product with aboiling point above 42F (216C).3.1.9 normalized product yieldthe result obtained wheneach product yield has been corrected for non-perfect massbalances
13、. For a run to be judged acceptable, the total recovery,wt % of feed, should be in the range of 96 to 101 % prior tonormalization. If the recovery is outside this range the test datashould be discarded.3.1.10 product yieldone hundred times the mass of aspecific product divided by the mass of feed us
14、ed in the test.1This 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 April 1, 2010. Published May 2010. Originallyapproved in 1991. Last previous edition approved in 2005 a
15、s D515405. DOI:10.1520/D5154-10.2For 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.3Available from National Inst
16、itute of Standards and Technology (NIST), 100Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http:/www.nist.gov.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.11 reaction severityan indication of the severity of thecracking
17、reaction which allows a range of conversions to beobtained from any particular catalyst without changing reactortemperature. Changing reaction severity is achieved by chang-ing WHSV or C/O ratio or both.3.1.12 weight hourly space velocity (WHSV)the oil feedrate in grams per hour divided by the mass
18、of catalyst in grams.Units are hr-1.4. Summary of Test Method4.1 At least two samples of FCC catalysts, one of which ischosen as a reference, are separately contacted with gas oil(ASTM Standard Feed or other suitable feedstock) in a fixedbed reactor at a specified reaction temperature and at more th
19、anone reaction severity. Reaction products (liquid, gas, and cokeon catalyst) are analyzed. Conversion, activity, and productyields are calculated for each experiment.4.2 Following analysis of the products, the total recovery(that is, mass balance) of the feed as converted and uncon-verted products
20、is determined. If the recovery is less than 96 %or greater than 101 %, the test is rejected as unsatisfactory.4.3 For each catalyst tested, normalized product yields areplotted against conversion or activity to generate a yield curve.The data comprising the yield curve may be used to obtain theparam
21、eters of an appropriate mathematical expression for thecurve. Comparisons among catalysts can be made by interpo-lating the yield curves to obtain the product yields at somespecified conversion.5. Significance and Use5.1 The microactivity test provides data to assess the rela-tive performance of FCC
22、 catalysts. Because results are affectedby catalyst pretreatment, feedstock characteristics, test equip-ment, and operating parameters, adherence to this test methodis a prerequisite for correct interpretation of results. Apparatus,test conditions, and analytical procedures actually used shouldclose
23、ly resemble those described in this test method. Signifi-cant variations in apparatus, test conditions and/or analyticalprocedures may result in activity and selectivity data which donot correlate with data developed by other laboratories onidentical catalyst/feedstock samples.5.2 The standard metho
24、d reaction temperature is 960F(516C). Other reaction temperatures can be used; however,catalyst selectivity data developed at temperatures other than960F (516C) may not correlate with selectivity data devel-oped at 960F (516C). Also, precision at other reactiontemperatures may change compared to dat
25、a obtained at 960F(516C).6. Apparatus6.1 The apparatus of this test method is essentially thatdescribed in Test Method D3907, as shown in Figs. 1-4, withthe addition of a gas collection system on the effluent gas ventline. In a typical gas collection system, a fluid is displaced bythe collected gas
26、and the volume of displaced liquid providesa quantitative measurement of the amount of gas collected. Tominimize the solubility of gases like H2and H2S in the fluid,a saturated brine (NaCl) solution is recommended. Somepublications have appeared which give example flow schemat-ics and more detailed
27、descriptions of typical apparatus.4Alternatively, there are several vendors as listed in ResearchReport RR:D32-10305who can provide specific equipment forperforming this test. However, Committee D32 can onlysuggest and will not recommend nor certify any specificvendor. Significant variations from th
28、e test apparatus of thismethod most likely will result in significantly different activityand selectivity data from identical catalyst samples.6.2 Chromatographic Equipment:6.2.1 Liquid product analyses should be performed usingTest Method D2887 on a gas chromatograph (G.C.) equippedwith a flame ion
29、ization detector.6.2.2 Gas product analyses may be accomplished in twoparts. First, an analysis using a G.C. equipped with a thermalconductivity detector, employing N2as a carrier gas, and usinga G.C. column that permits the separation and quantitativeidentification of H2and H2S. Second, an analysis
30、 using a G.C.equipped with a FID or TCD, employing He as a carrier gasand using a column that permits the separation and quantitative4Campagna, R. J., Wick, J. P., Brady, M. F., and Fort, D. L., “ Fresh FCCCatalyst Tests Predict Performance,” OGJ, March 24, 1986, p. 85.5Supporting data have been fil
31、ed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:D32-1030.NOTEThis drawing is not to scale. For engineering details, see otherdrawings.FIG. 1 Microactivity Flow ChartD5154 102identification of methane, ethane, ethylene, propane, propy-lene, n-butane, iso-buta
32、ne, 1-butene and iso-butene, cis-2-butene, and trans-2-butene, C5s and a C5+lump that is notresolved. The C5s and the C5+group are included as part of thegasoline fraction.6.3 Carbon analysis of a representative sample of the spentcatalyst (that is, after the cracking reaction has been com-pleted) m
33、ay be accomplished using a commercially availablecarbon analyzer.7. Sampling7.1 A sampling procedure is needed. Practice E105 isappropriate.8. Sample Preparation8.1 Equilibrium CatalystsDry samples or decoke, or both,by heating a shallow (less than 10 mm thick) bed of catalyst ina porcelain crucible
34、 at 1094 6 36F (590 6 20C) for a lengthof time sufficient to remove any coke. This typically requiresFIG. 2 Microactivity ReactorD5154 103FIG. 3 Reactor Feed Tube InsertD5154 104approximately three hours. Sufficient air should be available inthe furnace to burn the sample free of coke. Insufficientd
35、ecoking is indicated by a difference in color of the top andbottom layers. The hot crucible is cooled in a desiccator toprevent moisture pickup.NOTE 1Heavily coked samples may be damaged by sintering ordeactivation if oxidation is allowed to occur too rapidly, leading toartificially low catalytic ac
36、tivity and surface area.8.2 Fresh CatalystsFresh catalyst samples should besteam treated prior to selectivity testing. Steaming proceduressuch as those specified in Guide D4463 may be used. However,specific conditions (temperature, partial pressure of steam, andtime) should be chosen such that the s
37、teamed catalyst proper-ties (activity, zeolite and matrix surface areas, and unit cellsize) approximate those found in equilibrium FCC catalysts ofthe same type.9. Procedure9.1 Reactor Preparation:9.1.1 Rinse feed line with acetone or other suitable solventand dry with air. Periodic cleaning of the
38、insert is recom-mended by air purge at 1022F (550C) for one hour at leastonce every 12 tests.9.1.2 Wash the reactor and product receiver thoroughly withacetone or other suitable solvent and dry. If necessary, burn outany coke deposited in the reactor by heating in air at 960F(516C) prior to washing.
39、9.1.3 Insert a plug of quartz or borosilicate glass wool(about 20 mm length) until it reaches the constricted region ofthe reactor. Optionally, a reactor with a fritted disc may be usedto position the catalyst. Add 4.00 to 4.05 g of catalyst in afree-flowing manner. Tap the reactor lightly to ensure
40、 goodradial distribution (do not pack). Insert another plug of quartzor glass wool and add approximately 10 cc of 80 to 100 meshglass microspheres or crushed glass particles. These act as apreheat bed and aid in feed dispersion, especially at higherWHSVs.9.1.4 Inspect the oil insert needle to ensure
41、 it is clear ofdeposits. Place insert in reactor and adjust if necessary so thatthe bottom of the oil insert needle is just touching the top of theglass microsphere preheat bed (about 20 mm above the catalystbed). Inspect the reactor insert before using to be sure the tip ofthe thermocouple (see Fig
42、. 3, Detail 2) is bent under the tip ofthe syringe needle. (This is necessary to control the oil preheattemperature accurately.) Place the reactor in the furnace thathas been preheated to 960F (516C) and connect the nitrogenpurge line directly to the reactor feed line. Purge with 30 seem(30 mL/min)
43、of nitrogen for at least 30 min.9.1.5 Make electrical connections on the integral oil feedpreheater and connect the thermocouple to the recorder.9.2 Preparation of Syringe and Liquid Product Receiver:9.2.1 Preheat the gas oil feedstock to 104 6 9F (40 6 5C)to allow filling of the syringe. Before tes
44、ting, calibrate thesyringe pump to the correct feed rate by collecting the oil,preheated to 104 6 9F (40 6 5C), outside the reactor andweighing the oil or by weighing the syringe before and afterdelivery to assure the appropriate mass of oil delivered overunit time.NOTE 2If heavier feedstocks are us
45、ed, a syringe temperature of 158 69F (70 6 5C) should be used for obtaining accurate feed rates.9.2.2 Fill the syringe with preheated feedstock and invert toallow air to rise. Remove the air bubbles. The syringe shouldcontain a small amount of oil in excess of the nominal volumeto be charged.9.2.3 A
46、fter the syringe is filled and the valve is in the correctposition, blow excess oil out of the valve and clean the outsideof the syringe.9.2.4 Weigh the syringe assembly and record the mass.9.2.5 Attach the syringe and syringe valve to the reactormaking sure the valve is in the nitrogen flow positio
47、n. Athermocouple may be placed on the syringe body to monitorthe syringe temperature during oil injection.9.2.6 Obtain the initial mass of the liquid product receiv-er(s). If necessary, a second liquid receiver cooled by dry icemay be added in-line to aid collection of the lighter liquidproducts (ma
48、inly C5and C6s). If such a receiver is used, itshould also be weighed. Optionally, a small piece of glass woolin the receiver sidearm may be used to reduce the carryover ofC5+products into the gas collection vessel.9.2.7 Install receiver(s) and connect the gas line to the gascollection system. Open
49、the gas vent valve to prevent prema-ture collection of purge gas.9.2.8 Prepare and install wet ice (and dry ice) bath(s) for thereceiver(s). Immerse the receiver(s) to the level of the gasoutlet line(s). Optionally, a controlled temperature circulatingbath may be used in place of the wet ice bath.9.2.9 Pressurize the reactor to 150 mm Hg (20 kPa) nitrogenand close the gas vent and nitrogen supply valves. Watch thepressure gages for 2 min to determine if any significant leaksoccur. If no leaks are apparent, open the gas vent val
