Standard Guide for Determination of Chemical Elements in Fluid Catalytic Cracking Catalysts by X-ray Fluorescence Spectrometry (XRF)

SCOPE
1.1 This guide covers several comparable procedures for the quantitative chemical analysis of up to 29 elements in fluid catalytic cracking (FCC) catalyst by X-ray fluorescence spectrometry (XRF). Additional elements may be added.
1.2 This guide is applicable to fresh FCC catalyst, equilibrium FCC catalyst, spent FCC catalyst, and FCC catalyst fines.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory requirements prior to use.

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ASTM D7085-04 - Standard Guide for Determination of Chemical Elements in Fluid Catalytic Cracking Catalysts by X-ray Fluorescence Spectrometry (XRF)
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:D7085–04
Standard Guide for
Determination of Chemical Elements in Fluid Catalytic
Cracking Catalysts by X-ray Fluorescence Spectrometry
(XRF)
This standard is issued under the fixed designation D 7085; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope Sections 8-15) and fusing a powder into a glass bead (Test
Method B, Sections 16-23). This surface of the fused or
1.1 Thisguidecoversseveralcomparableproceduresforthe
briquetted specimen is irradiated with a primary source of X
quantitative chemical analysis of up to 29 elements in fluid
rays. The secondary X rays produced in the specimen are
catalytic cracking (FCC) catalyst by X-ray fluorescence spec-
characteristic of the chemical elements present in the speci-
trometry (XRF). Additional elements may be added.
men.TwotypesofXRFinstrumentationmaybeusedtocollect
1.2 This guide is applicable to fresh FCC catalyst, equilib-
and process the X-ray spectra. Using a wavelength-dispersive
rium FCC catalyst, spent FCC catalyst, and FCC catalyst fines.
X-ray spectrometer, the secondary X rays produced in the
1.3 This standard does not purport to address all of the
specimen are dispersed according to their wavelength by
safety concerns, if any, associated with its use. It is the
means of crystals or synthetic multilayers. The X-ray intensi-
responsibility of the user of this standard to establish appro-
ties are measured by detectors set at selected wavelengths and
priate safety and health practices and determine the applica-
recorded as counts (number of X rays impinging on the
bility of regulatory requirements prior to use.
detector per unit time). Concentrations of the elements are
2. Referenced Documents determined from the measured intensities using calibration
curves prepared from suitable reference materials. Using an
2.1 ASTM Standards:
energy-dispersive X-ray spectrometer, the secondary X rays
C 982 Guide for Selecting Components for Energy-
producedinthespecimenaresenttoadetectorwheretheentire
Dispersive X-ray Fluorescence (XRF) Systems
X-ray spectrum is electronically sorted according to the X-ray
C 1118 Guide for Selecting Components for Wavelength-
energy and processed into counts using a multichannel ana-
Dispersive X-ray Fluorescence (XRF) Systems
lyzer. The principal advantages of the wavelength-dispersive
D 1977 Test Method for Nickel and Vanadium in FCC
X-ray spectrometer are resolution and detection limit. The
Equilibrium Catalysts by Hydrofluoric/Sulfuric Acid De-
principal advantages of the energy-dispersive X-ray spectrom-
composition and Atomic Spectroscopic Analysis
eter are speed and a generally lower equipment cost.
E 1172 Practice for Describing and Specifying a
Wavelength-Dispersive X-ray Spectrometer
4. Significance and Use
E 1361 Guide for Correction of Interelement Effects in
4.1 The chemical composition of fresh FCC catalyst and
X-ray Spectrometric Analysis
equilibrium FCC catalyst is a predictor of catalyst perfor-
E 1621 Guide for X-ray Emission Spectrometric Analysis
mance.The analysis of catalyst fines also provides information
E 1622 Practice for Correction of Spectral Line Overlap in
on the performance of the FCC unit and the fines collection
Wavelength-Dispersive X-ray Spectrometry
device(s).
3. Summary of Guide
4.2 The chemical composition of equilibrium FCC catalyst
is a measure of the hazardous nature or toxicity of the material
3.1 The test specimen is prepared with a clean, uniform, flat
for purposes of disposal or secondary use.
surface. Two commonly used test methods of preparing test
specimens are listed: briquetting a powder (Test Method A,
5. Apparatus
5.1 X-ray Spectrometer, wavelength or energy-dispersive
This guide is under the jurisdiction ofASTM Committee D32 on Catalysts and system equipped with a vacuum sample chamber. Refer to
is the direct responsibility of Subcommittee D32.03 on Chemical Composition.
Guide C 982, Guide C 1118, and Practice E 1172 for informa-
Current edition approved Nov. 1, 2004. Published November 2004.
tion on specifying XRF systems.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
5.2 Muffle Furnace, capable of operating at 600°C.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D7085–04
5.3 Hot Plate, capable of maintaining a constant 200°C. 7.2 Prepare calibration standards using the same techniques
5.4 Porcelain Dishes, of a suitable size for calcining 50-g and reagents that will be used with the unknown samples.
sample aliquots. 7.2.1 Calibration standards can be prepared from previously
5.5 Vacuum Oven, capable of maintaining 60°C. This is analyzed samples where the accuracy and precision of the
required only if catalyst fines are to be analyzed. analysisisknown.Thisisthetypicalcalibrationmethodforthe
5.6 Vacuum Desiccators, useful for storing fusion beads or pressed powder technique. Up to 100 analyzed standards may
pressed pellets. be required for a full range calibration for 29 elements using
5.7 Fusion Equipment: the pressed powder technique.
7.2.2 Synthetic standards can be prepared from reagent-
5.7.1 Fusion Furnace or Fluxing Device, capable of oper-
ating at 1100°C. grade chemicals, analyzed samples, and certified reference
materials. This is the typical calibration method for the fusion
5.7.2 Fusion Crucibles and Molds, graphite or plati-
num–5 % gold alloy, sized to match the specimen holder of the technique.
7.3 Several tables, listed inAppendix X1, provide operating
X-ray spectrometer.
5.8 Pressed Pellet Equipment: information on the requirements necessary to establish a
pressed powder method for 29 elements in equilibrium FCC
5.8.1 Grinders or Pulverizers, manual (such as agate, mul-
catalyst.
lite, alumina, tungsten carbide, or boron carbide mortar and
pestle)orautomated(typicallywithatungstencarbidegrinding
TEST METHODS
vessel). Avoid steel grinding vessels.
5.8.2 Mixer Mill, useful for blending ground sample and
Test Method A—Pressed Powder
binder prior to preparing a pressed powder specimen.
5.8.3 Mixing Vials, sized to match the mixer mill.
8. Scope
5.8.4 Briquetting Press, capable of maintaining a reproduc-
ible pressure of at least 25 000 psi. This is required only if the
8.1 A test method example is provided for the analysis of
pressed powder method is utilized. Match mold size to the
nickel and vanadium in equilibrium FCC catalyst using either
specimenholderoftheX-rayspectrometer.Typicalsizesare25 a wavelength or an energy-dispersive X-ray spectrometer and
to 40 mm.
test specimens prepared by the pressed pellet technique.
8.2 This technique can be extended to other elements.
6. Reagents
9. Significance and Use
6.1 Reagents for Fusion Techniques:
9.1 In use, the FCC catalyst becomes contaminated with
6.1.1 Fluxes, lithium borates or carbonates or mixtures, of
ultrahigh purity. metals present in the feed oil. The levels of the contaminant
metals, particularly the catalyst poisons nickel and vanadium,
6.1.2 Non-Wetting Agents, such as lithium or ammonium
iodide, are frequently added to the flux, as are oxidizing agents can be used to predict catalyst performance.
such as lithium, potassium, or ammonium nitrate. Take care
10. Hazards
that adding non-wetting or oxidizing reagents does not cause
spectral interference with the analytes of interest.
10.1 Catalyst dust.
6.2 Reagents for Pressed Pellet Techniques:
10.2 X-ray radiation.
6.2.1 Heavy Absorber, barium or hafnium oxides are com-
10.3 Heat.
monly used as heavy absorbers, if that technique is applied.
10.4 High pressure.
6.2.2 Binders, required for the pressed powder technique.
These should not contribute any spectral interference. Micro-
11. Preparation of Apparatus
crystalline wax or cellulose with negligible levels of sodium or
11.1 Select the appropriate instrument for either a
potassium are suitable.
wavelength-dispersive or energy-dispersive technique. For
6.3 Detector Gas, for a wavelength dispersive system. The
these examples, use of energy-dispersive systems for analytes
typical gas for the flow-proportional counter is P-10: 10 %
below 1000 ppm would prove difficult. Assuming the FCC
methane and 90 % argon.
catalyst contains rare earths, the difficulty increases because,
6.4 2-propanol, ACS reagent grade.
by energy-dispersive X-ray fluorescence spectrometry
6.5 Calibration References, commercially available stan-
(EDXRF),rareearthsarepoorlyresolvedandcreatesignificant
dard or certified reference materials or locally prepared mix-
matrix effects.
tures from ultra high purity materials that include the elements
11.2 Read Guide E 1621, Guide E 1361, and Practice
of interest in the concentration ranges expected in unknown
E 1622. These will provide a general knowledge of the
samples.
function of a wavelength-dispersive X-ray spectrometer.
6.6 Standard Solutions, 10 000 µg/mL of nickel and 10 000
11.3 Set up the instrument using the vendor’s manual.
µg/mL of vanadium.
Modern X-ray spectrometers are equipped with software that
guides the operator through the steps necessary to create an
7. Procedure
analytical program for a specific analysis. For this example,
7.1 Prepare specimens using either a pressed powder or a analysis of equilibrium FCC for nickel and vanadium, typical
fusion technique. instrument conditions are given in Appendix X1.
D7085–04
TABLE 1 Precision Values
12. Calibration and Standardization
Mean Concentration, % 62 s (95 % C.I.) %RSD
12.1 Preparation of Calibration Standards:
Al O 29.92 0.16 0.27
2 3
12.1.1 Assemble a minimum of five catalyst samples with
SiO 65.48 0.49 0.37
nickel and vanadium concentrations that cover the range of
Ni 0.2332 0.0051 1.1
interest. This test method is specific for a single grade of
V 0.2417 0.0028 0.58
Fe 0.54 0.01 0.78
catalyst and is limited to material where only the nickel and
Cu 0.0045 0.0002 1.7
vanadium content varies.
TiO 1.03 0.01 0.49
12.1.2 Prepare each catalyst sample in duplicate in accor-
Mn 0.0040 0.0003 4.1
Co 0.0142 0.0006 2.0
dance with Section 13, saving a portion of the calcined and
Na 0.60 0.01 0.73
ground specimen for the next step.
MgO 0.085 0.004 2.5
12.1.3 Determine the nickel and vanadium content of the P O 0.340 0.009 1.2
2 5
CaO 0.16 0.005 1.7
materials prepared in 12.1.2 using a comparative analytical
SO 0.17 0.01 2.3
technique such as Test Method D 1977.
Sb 0.0862 0.0013 0.77
12.2 Calibrate the instrument using the prepared standards ZnO 0.0255 0.0007 1.4
Pb 0.0077 0.0002 1.4
following the vendor’s recommended procedure.
Ba 0.030 0.002 3.3
La O 0.84 0.01 0.47
2 3
13. Preparation of the Test Specimen CeO 0.37 0.01 1.3
Nd O 0.42 0.01 0.93
2 3
13.1 Heat approximately 50 g of specimen in a muffle
Pr O 0.13 0.01 2.3
6 11
Sm O 0.01 0.001 6.0
furnace at 600°C with a bed depth less than 25 mm for a 2 3
Total REO 1.77 0.01 0.60
minimum of 1 h, if it is fresh catalyst, or up to3hto remove
K O 0.10 0.002 0.92
carbon from spent catalyst, equilibrium catalyst, or catalyst
Sr 0.011 0.001 2.9
Zr 0.009 0.001 6.0
fines.
13.2 Grind approximately 20 to 30 g of the heated specimen
to less than 30 µm. Homogenize the material if it was ground
in several batches.
15. Precision and Bias
13.3 Combine the ground specimen with binder at a prede-
15.1 The precision values listed in Table 1 were obtained
termined ratio into a mixing vial with mixing beads added to
from one sample of equilibrium FCC catalyst, prepared and
promote agitation. Typically, the binder is blended at a ratio of
analyzed 16 times. The % relative standard deviation (RSD) is
1 part binder to 3 to 5 parts sample and chosen to give
defined as:
consistent and stable pellets.
%RSD 5 ~s / mean concentration! 3 100
NOTE 1—As an example, 1.5 6 0.01 g of a micronized high molecular
weight paraffin wax binder is mixed with 6.5 6 0.01 g of the ground
Test Method B—Fused Bead
specimen.
13.4 Place the mixing vial into a mixing mill for 10 min to
16. Scope
thoroughly mix/blend the specimen and binder.
16.1 A test method example is provided for the analysis of
13.5 Place the contents of the mixing vial onto a piece of
nickel and vanadium in equilibrium FCC catalyst using either
weighing paper. Remove and discard the mixing beads.
a wavelength or an energy-dispersive X-ray spectrometer and
13.6 Transfer the contents of the weighing paper to the
using test specimens prepared by the fused bead technique.
briquetting press, which has been previously cleaned with
2-propanol, and spread evenly over the surface of the mold or
17. Significance and Use
optionally press into an aluminum cap.
17.1 In use, the FCC catalyst becomes contaminated with
13.7 Press the specimen at a ram pressure of between
metals present in the feed oil. The levels of the contaminant
25 000 and 60 000 psi. The pressure used will depend on the
metals, particularly the catalyst poisons nickel and vanadium,
binder and binder/sample ratio and is usually determined
can be used to predict catalyst performance.
empirically. For this binder example, a typical ram pressure is
30 000 psi for 10 6 2 s for a 40-mm mold.
18. Hazards
13.8 Attachanidentifyinglabeltothebacksideofthepellet.
Typically, the top surface is the analytical surface. Avoid
18.1 Catalyst dust.
touching this surface when handling the briquetted pellet.
18.2 Flux dust.
13.9 Store the pressed powder specimens in a vacuum
18.3 Heat.
desiccatortopreventmoisturepickuporcontaminationpriorto
18.4 X-ray radiation.
analysis.
19. Preparation of Apparatus
14. Procedure
19.1 Select the appropriate instrument for either a
14.1 Analyze the prepared specimens following the ven- wavelength-dispersive or energy-dispersive technique. For
dor’srecommendedprocedureusingthecalibrationestablished these examples, use of energy-dispersive systems for analytes
previously in 12.2. below 1000 ppm would prove difficult. Assuming the FCC
D7085–04
catalyst contains rare earths, the difficulty increases because, 20.2.11 Determine the desired calibration range for the
by EDXRF, rare earths are poorly resolved and create signifi- nickel and vanadium. Using the examples above, prepare five
cant matrix effects. crucibles for nickel and five crucibles for vanadium.
19.2 Read Guide E 1621, Guide E 1361, and Practice 20.2.12 Fuse the mixture at 1100 6 100°C in a f
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