ASTM D7085-04(2010)e1
(Guide)Standard Guide for Determination of Chemical Elements in Fluid Catalytic Cracking Catalysts by X-ray Fluorescence Spectrometry (XRF)
Standard Guide for Determination of Chemical Elements in Fluid Catalytic Cracking Catalysts by X-ray Fluorescence Spectrometry (XRF)
SIGNIFICANCE AND USE
The chemical composition of fresh FCC catalyst and equilibrium FCC catalyst is a predictor of catalyst performance. The analysis of catalyst fines also provides information on the performance of the FCC unit and the fines collection device(s).
The chemical composition of equilibrium FCC catalyst is a measure of the hazardous nature or toxicity of the material for purposes of disposal or secondary use.
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 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3.1 The units of ppm (mg/kg) are used instead of wt% in Tables X2.3-X2.5 for reporting concentration of certain elements because of industry convention and because most of these elements are present at trace levels.
1.4 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.
8.1 A test method example is provided for the analysis of nickel and vanadium in equilibrium FCC catalyst using either a wavelength or an energy-dispersive X-ray spectrometer and test specimens prepared by the pressed pellet technique.
8.2 This technique can be extended to other elements.
16.1 A test method example is provided for the analysis of nickel and vanadium in equilibrium FCC catalyst using either a wavelength or an energy-dispersive X-ray spectrometer and using test specimens prepared by the fused bead technique.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
´1
Designation: D7085 − 04 (Reapproved 2010)
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 D7085; 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 (´) indicates an editorial change since the last revision or reapproval.
´ NOTE—Updated Scope and text to reflect the use of ppm and SI units editorially in April 2010.
1. Scope D1977 Test Method for Nickel and Vanadium in FCC
Equilibrium Catalysts by Hydrofluoric/Sulfuric Acid De-
1.1 Thisguidecoversseveralcomparableproceduresforthe
composition and Atomic Spectroscopic Analysis
quantitative chemical analysis of up to 29 elements in fluid
E1172 PracticeforDescribingandSpecifyingaWavelength-
catalytic cracking (FCC) catalyst by X-ray fluorescence spec-
Dispersive X-Ray Spectrometer
trometry (XRF). Additional elements may be added.
E1361 Guide for Correction of Interelement Effects in
1.2 This guide is applicable to fresh FCC catalyst, equilib-
X-Ray Spectrometric Analysis
rium FCC catalyst, spent FCC catalyst, and FCC catalyst fines.
E1621 Guide for X-Ray Emission Spectrometric Analysis
1.3 The values stated in SI units are to be regarded as
E1622 Practice for Correction of Spectral Line Overlap in
standard. No other units of measurement are included in this Wavelength-Dispersive X-Ray Spectrometry (Withdrawn
standard.
2006)
1.3.1 The units of ppm (mg/kg) are used instead of wt% in
Tables X2.3-X2.5 for reporting concentration of certain ele-
3. Summary of Guide
ments because of industry convention and because most of
3.1 The test specimen is prepared with a clean, uniform, flat
these elements are present at trace levels.
surface. Two commonly used test methods of preparing test
1.4 This standard does not purport to address all of the
specimens are listed: briquetting a powder (Test Method A,
safety concerns, if any, associated with its use. It is the
Sections 8-15) and fusing a powder into a glass bead (Test
responsibility of the user of this standard to establish appro-
Method B, Sections 16-23). This surface of the fused or
priate safety and health practices and determine the applica-
briquetted specimen is irradiated with a primary source of X
bility of regulatory requirements prior to use.
rays. The secondary X rays produced in the specimen are
characteristic of the chemical elements present in the speci-
2. Referenced Documents
men.TwotypesofXRFinstrumentationmaybeusedtocollect
2.1 ASTM Standards:
and process the X-ray spectra. Using a wavelength-dispersive
C982 Guide for Selecting Components for Energy-
X-ray spectrometer, the secondary X rays produced in the
Dispersive X-Ray Fluorescence (XRF) Systems (With-
specimen are dispersed according to their wavelength by
drawn 2008)
means of crystals or synthetic multilayers. The X-ray intensi-
C1118 Guide for Selecting Components for Wavelength-
ties are measured by detectors set at selected wavelengths and
Dispersive X-Ray Fluorescence (XRF) Systems (With-
recorded as counts (number of X rays impinging on the
drawn 2011)
detector per unit time). Concentrations of the elements are
determined from the measured intensities using calibration
1 curves prepared from suitable reference materials. Using an
This guide is under the jurisdiction ofASTM Committee D32 on Catalysts and
is the direct responsibility of Subcommittee D32.03 on Chemical Composition.
energy-dispersive X-ray spectrometer, the secondary X rays
Current edition approved April 1, 2010. Published May 2010. Originally
producedinthespecimenaresenttoadetectorwheretheentire
ϵ1
approved in 2004. Last previous edition approved in 2004 as D7085–04 .
X-ray spectrum is electronically sorted according to the X-ray
DOI:10.1520/D7085-04R10E01.
energy and processed into counts using a multichannel ana-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
lyzer. The principal advantages of the wavelength-dispersive
Standards volume information, refer to the standard’s Document Summary page on
X-ray spectrometer are resolution and detection limit. The
the ASTM website.
principal advantages of the energy-dispersive X-ray spectrom-
The last approved version of this historical standard is referenced on
www.astm.org. eter are speed and a generally lower equipment cost.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D7085 − 04 (2010)
4. Significance and Use 6.2.2 Binders, required for the pressed powder technique.
These should not contribute any spectral interference. Micro-
4.1 The chemical composition of fresh FCC catalyst and
crystalline wax or cellulose with negligible levels of sodium or
equilibrium FCC catalyst is a predictor of catalyst perfor-
potassium are suitable.
mance.The analysis of catalyst fines also provides information
on the performance of the FCC unit and the fines collection 6.3 Detector Gas, for a wavelength dispersive system. The
device(s). typical gas for the flow-proportional counter is P-10: 10 %
methane and 90 % argon.
4.2 The chemical composition of equilibrium FCC catalyst
is a measure of the hazardous nature or toxicity of the material 6.4 2-propanol, ACS reagent grade.
for purposes of disposal or secondary use.
6.5 Calibration References, commercially available stan-
dard or certified reference materials or locally prepared mix-
5. Apparatus
tures from ultra high purity materials that include the elements
5.1 X-ray Spectrometer, wavelength or energy-dispersive
of interest in the concentration ranges expected in unknown
system equipped with a vacuum sample chamber. Refer to
samples.
Guide C982, Guide C1118, and Practice E1172 for information
6.6 Standard Solutions, 10 000 µg/mL of nickel and 10 000
on specifying XRF systems.
µg/mL of vanadium.
5.2 Muffle Furnace, capable of operating at 600°C.
7. Procedure
5.3 Hot Plate, capable of maintaining a constant 200°C.
7.1 Prepare specimens using either a pressed powder or a
5.4 Porcelain Dishes, of a suitable size for calcining 50-g
fusion technique.
sample aliquots.
7.2 Prepare calibration standards using the same techniques
5.5 Vacuum Oven, capable of maintaining 60°C. This is
and reagents that will be used with the unknown samples.
required only if catalyst fines are to be analyzed.
7.2.1 Calibration standards can be prepared from previously
5.6 Vacuum Desiccators, useful for storing fusion beads or
analyzed samples where the accuracy and precision of the
pressed pellets.
analysisisknown.Thisisthetypicalcalibrationmethodforthe
5.7 Fusion Equipment: pressed powder technique. Up to 100 analyzed standards may
be required for a full range calibration for 29 elements using
5.7.1 Fusion Furnace or Fluxing Device, capable of oper-
ating at 1100°C. the pressed powder technique.
7.2.2 Synthetic standards can be prepared from reagent-
5.7.2 Fusion Crucibles and Molds, graphite or plati-
grade chemicals, analyzed samples, and certified reference
num–5 % gold alloy, sized to match the specimen holder of the
materials. This is the typical calibration method for the fusion
X-ray spectrometer.
technique.
5.8 Pressed Pellet Equipment:
7.3 Several tables, listed in Appendix X1, provide operating
5.8.1 Grinders or Pulverizers, manual (such as agate,
information on the requirements necessary to establish a
mullite,alumina,tungstencarbide,orboroncarbidemortarand
pressed powder method for 29 elements in equilibrium FCC
pestle)orautomated(typicallywithatungstencarbidegrinding
catalyst.
vessel). Avoid steel grinding vessels.
5.8.2 Mixer Mill, useful for blending ground sample and
TEST METHODS
binder prior to preparing a pressed powder specimen.
5.8.3 Mixing Vials, sized to match the mixer mill.
Test Method A—Pressed Powder
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. Scope
pressed powder method is utilized. Match mold size to the
8.1 A test method example is provided for the analysis of
specimenholderoftheX-rayspectrometer.Typicalsizesare25
nickel and vanadium in equilibrium FCC catalyst using either
to 40 mm.
a wavelength or an energy-dispersive X-ray spectrometer and
test specimens prepared by the pressed pellet technique.
6. Reagents
8.2 This technique can be extended to other elements.
6.1 Reagents for Fusion Techniques:
6.1.1 Fluxes, lithium borates or carbonates or mixtures, of
9. Significance and Use
ultrahigh purity.
9.1 In use, the FCC catalyst becomes contaminated with
6.1.2 Non-Wetting Agents, such as lithium or ammonium
metals present in the feed oil. The levels of the contaminant
iodide, are frequently added to the flux, as are oxidizing agents
metals, particularly the catalyst poisons nickel and vanadium,
such as lithium, potassium, or ammonium nitrate. Take care
can be used to predict catalyst performance.
that adding non-wetting or oxidizing reagents does not cause
spectral interference with the analytes of interest.
10. Hazards
6.2 Reagents for Pressed Pellet Techniques:
10.1 Catalyst dust.
6.2.1 Heavy Absorber, barium or hafnium oxides are com-
monly used as heavy absorbers, if that technique is applied. 10.2 X-ray radiation.
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D7085 − 04 (2010)
TABLE 1 Precision Values
10.3 Heat.
Mean Concentration, % ±2 σ (95 % C.I.) %RSD
10.4 High pressure.
Al O 29.92 0.16 0.27
2 3
SiO 65.48 0.49 0.37
11. Preparation of Apparatus
Ni 0.2332 0.0051 1.1
V 0.2417 0.0028 0.58
11.1 Select the appropriate instrument for either a
Fe 0.54 0.01 0.78
wavelength-dispersive or energy-dispersive technique. For
Cu 0.0045 0.0002 1.7
these examples, use of energy-dispersive systems for analytes
TiO 1.03 0.01 0.49
Mn 0.0040 0.0003 4.1
below 0.1 wt% would prove difficult. Assuming the FCC
Co 0.0142 0.0006 2.0
catalyst contains rare earths, the difficulty increases because,
Na 0.60 0.01 0.73
by energy-dispersive X-ray fluorescence spectrometry
MgO 0.085 0.004 2.5
P O 0.340 0.009 1.2
(EDXRF),rareearthsarepoorlyresolvedandcreatesignificant 2 5
CaO 0.16 0.005 1.7
matrix effects.
SO 0.17 0.01 2.3
Sb 0.0862 0.0013 0.77
11.2 Read Guide E1621, Guide E1361, and Practice E1622.
ZnO 0.0255 0.0007 1.4
These will provide a general knowledge of the function of a
Pb 0.0077 0.0002 1.4
wavelength-dispersive X-ray spectrometer. Ba 0.030 0.002 3.3
La O 0.84 0.01 0.47
2 3
11.3 Set up the instrument using the vendor’s manual.
CeO 0.37 0.01 1.3
Nd O 0.42 0.01 0.93
Modern X-ray spectrometers are equipped with software that 2 3
Pr O 0.13 0.01 2.3
6 11
guides the operator through the steps necessary to create an
Sm O 0.01 0.001 6.0
2 3
analytical program for a specific analysis. For this example,
Total REO 1.77 0.01 0.60
K O 0.10 0.002 0.92
analysis of equilibrium FCC for nickel and vanadium, typical 2
Sr 0.011 0.001 2.9
instrument conditions are given in Appendix X1.
Zr 0.009 0.001 6.0
12. Calibration and Standardization
12.1 Preparation of Calibration Standards:
12.1.1 Assemble a minimum of five catalyst samples with
nickel and vanadium concentrations that cover the range of
13.5 Place the contents of the mixing vial onto a piece of
interest. This test method is specific for a single grade of
weighing paper. Remove and discard the mixing beads.
catalyst and is limited to material where only the nickel and
13.6 Transfer the contents of the weighing paper to the
vanadium content varies.
briquetting press, which has been previously cleaned with
12.1.2 Prepare each catalyst sample in duplicate in accor-
2-propanol, and spread evenly over the surface of the mold or
dance with Section 13, saving a portion of the calcined and
optionally press into an aluminum cap.
ground specimen for the next step.
12.1.3 Determine the nickel and vanadium content of the
13.7 Press the specimen at a ram pressure of between
materials prepared in 12.1.2 using a comparative analytical
25 000 and 60 000 psi. The pressure used will depend on the
technique such as Test Method D1977.
binder and binder/sample ratio and is usually determined
12.2 Calibrate the instrument using the prepared standards empirically. For this binder example, a typical ram pressure is
following the vendor’s recommended procedure.
30 000 psi for 10 6 2 s for a 40-mm mold.
13.8 Attachanidentifyinglabeltothebacksideofthepellet.
13. Preparation of the Test Specimen
Typically, the top surface is the analytical surface. Avoid
13.1 Heat approximately 50 g of specimen in a muffle
touching this surface when handling the briquetted pellet.
furnace at 600°C with a bed depth less than 25 mm for a
minimum of 1 h, if it is fresh catalyst, or up to3hto remove
13.9 Store the pressed powder specimens in a vacuum
carbon from spent catalyst, equilibrium catalyst, or catalyst
desiccatortopreventmoisturepickuporcontaminationpriorto
fines.
analysis.
13.2 Grind approximately 20 to 30 g of the heated specimen
14. Procedure
to less than 30 µm. Homogenize the material if it was ground
in several batches.
14.1 Analyze the prepared specimens following the ven-
dor’srecommendedprocedureusingthecalibrationestablished
13.3 Combine the ground specimen with binder at a prede-
termined ratio into a mixing vial with mixing beads added to previously in 12.2.
promote agitation. Typically, the binder is blended at a ratio of
1 part binder to 3 to 5 parts sample and chosen to give 15. Precision and Bias
consistent and stable pellets.
15.1 The precision values listed in Table 1 were obtained
NOTE 1—As an example, 1.5 6 0.01 g of a micronized high molecular
from one sample of equilibrium FCC catalyst, prepared and
weight paraffin wax binder is mixed with 6.5 6 0.01 g of the ground
analyzed 16 times. The % relative standard deviation (RSD) is
specimen.
defined as:
13.4 Place the mixing vial into a mixing mill for 10 min to
thoroughly mix/blend the specimen and binder. %RSD 5 σ/mean concentration 3100
~ !
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D7085 − 04 (2010)
Test Method B—Fused Bead 20.2.3 Weigh into a clean, dry fusion crucible 1.00 6 0.01 g
of calcined catalyst and 5.00 6 0.01 g of flux; thoroughly mix
16. Scope the sample and flux.
16.1 A test method example is provided for the analysis of
NOTE 3—In this example, use Pt/5 % gold alloy crucibles and a
commercially available fluxer. Other flux to sample ratios like 5:2 and
nickel and vanadium in equilibrium FCC catalyst using either
10:1 can be used. A suitable flux is 49.75 % lithium metaborate, 49.75 %
a wavelength or an energy-dispersive X-ray sp
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