ASTM D5357-03(2013)
(Test Method)Standard Test Method for Determination of Relative Crystallinity of Zeolite Sodium A by X-ray Diffraction
Standard Test Method for Determination of Relative Crystallinity of Zeolite Sodium A by X-ray Diffraction
SIGNIFICANCE AND USE
4.1 Zeolite NaA has been used as an active component in molecular sieves employed as desiccants for natural gas, process gas streams, sealed insulated windows, and as a builder (water softener) in household laundry detergents.
4.2 This X-ray procedure is designed to allow a reporting of the relative degree of crystallization of NaA in the manufacture of NaA. The relative crystallinity number has proven useful in technology, research, and specifications.
4.3 Drastic changes in intensity of individual peaks in the XRD pattern of NaA can result from changes in distribution of electron density within the unit cell of the NaA zeolite. The electron density distribution is dependent upon the extent of filling of pores in the zeolite with guest molecules, and on the nature of the guest molecules. In this XRD method, the guest molecule H2O completely fills the pores. Intensity changes may also result if some or all of the sodium cations in NaA are exchanged by other cations.
4.4 Drastic changes in overall intensity can result from changes in X-ray absorption attributed to non-crystalline phases, if present, in a NaA sample. If non-zeolite crystalline phases are present, their diffraction peaks may overlap with some of the NaA diffraction peaks selected for this test method. If there is reason to suspect the presence of such components, then NaA peaks free of interference should be chosen for analysis.
SCOPE
1.1 This test method covers a procedure for determining the relative crystallinity of zeolite sodium A (zeolite NaA) using selected peaks from the X-ray diffraction pattern of the zeolite.
1.2 The term “intensity of an X-ray powder diffraction (XRD) peak” refers to the “integral intensity,” either the area or counts under the peak or the product of the peak height and the peak width at half height.
1.3 This test method provides a number that is the ratio of intensity of portions of the XRD pattern of the sample to intensity of the corresponding portion of the pattern of a reference zeolite NaA. The intensity ratio, expressed as a percentage, is then labeled relative crystallinity of NaA.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 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 limitations prior to use.
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Standards Content (Sample)
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Designation: D5357 − 03 (Reapproved 2013)
Standard Test Method for
Determination of Relative Crystallinity of Zeolite Sodium A
by X-ray Diffraction
This standard is issued under the fixed designation D5357; 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.
1. Scope 3. Summary of Test Method
1.1 This test method covers a procedure for determining the 3.1 The XRD patterns of the zeolite NaA or zeolite NaA-
relative crystallinity of zeolite sodium A (zeolite NaA) using containing sample and the reference sample (NaA) are ob-
selected peaks from the X-ray diffraction pattern of the zeolite. tained under the same conditions.Acomparison of the sums of
intensities of six strong peaks in the 11–32° 2θ range is made,
1.2 The term “intensity of an X-ray powder diffraction
giving relative crystallinity of NaA.This type of comparison is
(XRD)peak”referstothe“integralintensity,”eithertheareaor
commonlyusedinzeolitetechnologyandisoftenreferredtoas
counts under the peak or the product of the peak height and the
“% crystallinity.”
peak width at half height.
1.3 This test method provides a number that is the ratio of 4. Significance and Use
intensity of portions of the XRD pattern of the sample to
4.1 Zeolite NaA has been used as an active component in
intensity of the corresponding portion of the pattern of a
molecular sieves employed as desiccants for natural gas,
reference zeolite NaA. The intensity ratio, expressed as a
processgasstreams,sealedinsulatedwindows,andasabuilder
percentage, is then labeled relative crystallinity of NaA.
(water softener) in household laundry detergents.
1.4 The values stated in SI units are to be regarded as
4.2 This X-ray procedure is designed to allow a reporting of
standard. No other units of measurement are included in this
the relative degree of crystallization of NaAin the manufacture
standard.
of NaA. The relative crystallinity number has proven useful in
1.5 This standard does not purport to address all of the
technology, research, and specifications.
safety concerns, if any, associated with its use. It is the
4.3 Drastic changes in intensity of individual peaks in the
responsibility of the user of this standard to establish appro-
XRD pattern of NaAcan result from changes in distribution of
priate safety and health practices and determine the applica-
electron density within the unit cell of the NaA zeolite. The
bility of regulatory limitations prior to use.
electron density distribution is dependent upon the extent of
filling of pores in the zeolite with guest molecules, and on the
2. Referenced Documents
nature of the guest molecules. In this XRD method, the guest
2.1 ASTM Standards:
molecule H O completely fills the pores. Intensity changes
D3906 Test Method for Determination of Relative X-ray
may also result if some or all of the sodium cations in NaAare
Diffraction Intensities of Faujasite-Type Zeolite-
exchanged by other cations.
Containing Materials
4.4 Drastic changes in overall intensity can result from
E177 Practice for Use of the Terms Precision and Bias in
changes in X-ray absorption attributed to non-crystalline
ASTM Test Methods
phases, if present, in a NaA sample. If non-zeolite crystalline
E456 Terminology Relating to Quality and Statistics
phases are present, their diffraction peaks may overlap with
E691 Practice for Conducting an Interlaboratory Study to
someoftheNaAdiffractionpeaksselectedforthistestmethod.
Determine the Precision of a Test Method
If there is reason to suspect the presence of such components,
then NaA peaks free of interference should be chosen for
1 analysis.
This test method is under the jurisdiction of ASTM Committee D32 on
Catalysts and is the direct responsibility of Subcommittee D32.05 on Zeolites.
Current edition approved Dec. 1, 2013. Published December 2013. Originally 5. Apparatus
ε1
approved in 1993. Last previous edition approved in 2008 as D5357 – 03 (2008) .
5.1 X–ray Diffractometer, equipped with computerized data
DOI: 10.1520/D5357-03R13.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or acquisition and reduction capability or with a strip chart
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
recorder, and using copper K-alpha radiation.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. 5.2 Drying Oven, set at 100°C.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D5357 − 03 (2013)
FIG. 1 X-Ray Diffraction Pattern of Zeolite NaA—ASTM Sample Z-02
5.3 Hydrator (Laboratory Desiccator), maintained at about content samples. This scan range includes the six strong
58 % relative humidity by a saturated solution of sodium diffraction peaks that are to be used in the calculation for “%
bromide, NaBr. crystallinity”:
hkl index d (Angstrom) °2θ (Cu K-α radiation)
5.4 Planimeter or Appropriate Peak Profile Analysis or
222 7.104 12.46
Digital Integration Software, if diffractometer is not equipped
420 5.503 16.11
with appropriate software data analysis capability.
442 4.102 21.67
620 3.710 23.99
642 3.289 27.12
6. Reagents and Materials
644 2.984 29.94
6.1 NaA Powder , as reference standard, preferably with a
Fig. 1 shows a pattern for the reference zeolite NaA used in
mean particle diameter of 3 to 5 microns (mean crystal size 1
testing of this method.
to 2 microns).
NOTE 3—1 nanometer (nm) = 10 Angstroms.
7. Procedure
7.1.3.1 If a strip chart recorder is used, set the chart drive at
20 mm/min. Select the scale factor (amplification) for the NaA
7.1 Carry out the steps (described in 7.1.1 – 7.1.3)inan
reference pattern so that the strong (644) peak at 29.94° is
identical manner for both the sample and the NaA reference.
between 50 and 100 % of full scale. The same scale factor
7.1.1 Place abo
...
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