ASTM D7084-04(2009)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D7084 − 04 (Reapproved 2009)
Standard Test Method for
Determination of Bulk Crush Strength of Catalysts and
Catalyst Carriers
This standard is issued under the fixed designation D7084; 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 3.1.3 generated fines—particle size after crushing that
passes through a sieve one-half of the diameter of the catalyst
1.1 This test method covers the determination of bulk crush
pellet.
1 3
strength of a bed of formed catalyst particles ⁄32 to ⁄16 in. (0.8
to 4.8 mm) in diameter and is intended to provide information
4. Summary of Test Method
concerning the ability of the catalyst material to maintain
4.1 Arepresentativesampleisplacedinacylindricalsample
physical integrity.
holder, which is fitted with a piston. The piston is allowed to
1.2 The values stated in inch-pound units are to be regarded
compress the catalyst at a known pressure. The percent of
as standard. The values given in parentheses are mathematical
generated fines is determined by sieving.
conversions to SI units that are provided for information only
and are not considered standard.
5. Significance and Use
1.3 This standard does not purport to address all of the
5.1 This test method is a means of determining the crushing
safety concerns, if any, associated with its use. It is the
strength of a catalyst in a bed. Techniques to measure the
responsibility of the user of this standard to establish appro-
crushing strength of formed catalyst particles is limited to
priate safety and health practices and determine the applica-
crushing of individual particles, which may not be related to
bility of regulatory limitations prior to use.
how the catalyst will crush in a reactor or bed. For some
catalysts, such as granules, this technique may be the only
2. Referenced Documents
viable method for obtaining crushing strength. The production
2.1 ASTM Standards:
of fines in a reactor is not desired because of the potential of
D3766 Terminology Relating to Catalysts and Catalysis
bed compaction and the pressure buildup in the reactor.
D4180 Test Method for Vibratory Packing Density of
Formed Catalyst Particles and Catalyst Carriers
6. Apparatus
E177 Practice for Use of the Terms Precision and Bias in
6.1 Hydraulic Press, capable of 3200 lb (1450 kg) loading,
ASTM Test Methods
including a force gage. Maximum load capacity of the press
E456 Terminology Relating to Quality and Statistics
should match with the accuracy measuring the applied force.
E691 Practice for Conducting an Interlaboratory Study to
NOTE 1—Lower maximum load may be acceptable for testing less
Determine the Precision of a Test Method
strong materials.
3. Terminology
6.2 U.S. Standard Sieves, set (Tyler Equivalent).
3.1 Definitions:
6.3 Test Cell, (Fig. 1).
3.1.1 See also Terminology D3766.
NOTE 2—Atop loading cell can be used, but reproducibility of this test
3.1.2 bulk crush strength—pressure that generates 1 % fines is a function of the volume being crushed and therefore the constant
volume cell, as shown in Fig. 1, is recommended. A smaller l/d ratio for
for a sample contained in a cylindrical sample holder and
the cell will alter the results, and for certain applications, it may be more
crushed with a piston.
3,4
desirable.
6.4 Drying Oven.
This test method is under the jurisdiction of ASTM Committee D32 on
Catalysts and is the direct responsibility of Subcommittee D32.02 on Physical-
6.5 Balance, having a sensitivity of 0.1 g.
Mechanical Properties.
Current edition approved March 1, 2009. Published March 2009. Originally
approved in 2004. Last previous edition approved in 2004 as D7084–04. DOI:
10.1520/D7084-04R09. Bradley, S.A., Pitzer, E., and Koves, W. J., “Bulk Crush Testing of Catalysts,”
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Characterization and Catalyst Development,ACS Symposium Series 411, Bradley,
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM S. A., Gattuso, M. J., and Bertolacini, R. J., Eds., 1989, pp. 398-406.
Standards volume information, refer to the standard’s Document Summary page on Adams, A. R., Sartor, A. F., and Welsh, J. G., “Problems in Standardizing
the ASTM website. Catalyst Tests,” Chemical Engineering Progress, Vol 71, 1975, pp. 35-37.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7084 − 04 (2009)
FIG. 1 Test Cell
6.6 Glass Cylinders,with 250-mLfeed capacity. Measure in 7.5 Weigh sufficient sample for nine crushing operations.
accordance with Test Method D4180. Sieve the sample using a sieve that is one-half the diameter of
the catalyst pellet. If 10 % of the material passes through the
6.7 Vibrator, conventional, handheld, with hard rubber or
screen, use a smaller sieve size. Dry the sample at 673 K for 3
metal impactor, in accordance with Test Method D4180.
h; do not exceed a bed height of 1 in. Cool the sample in a
6.8 Feed Funnel.
desiccator.
6.9 Desiccator, with grade molecular sieve, such as 4A.
7.6 Weigh a sample required to fill a volume of 49 cm,as
determined in 7.4. Keep the remaining sample in the desicca-
7. Procedure
tor.
7.1 Determine the bulk density in accordance with Test
Method D4180. 7.7 Fill the cell with the 49-cm dried sample. Tap the cell
while filling it. Place the entire catalyst sample into the cell.
7.2 Weigh 100
...