ASTM D4365-95(2008)

Standard Test Method for Determining Micropore Volume and Zeolite Area of a Catalyst

SIGNIFICANCE AND USE
This gas adsorption method complements the X-ray procedure of Test Method D 3906. This test method will be useful to laboratories that do not have X-ray diffractometers. Each test method can be calibrated by use of an appropriate series of mechanical mixtures to provide what may be termed percent zeolite. If there is disorder in the zeolite, the adsorption method will yield higher values than the X-ray method. The reverse will be true if some zeolite pores (micropores) are blocked or filled.
SCOPE
1.1 This test method covers the determination of total surface area and mesopore area. From these results are calculated the zeolite area and micropore volume of a zeolite containing catalyst. The micropore volume is related to the percent zeolite in the catalyst. The zeolite area, a number related to the surface area within the zeolite pores, may also be calculated. Zeolite area, however, is difficult to intepret in physical terms because of the manner in which nitrogen molecules pack within the zeolite.
1.2 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. For a specific precautionary statement, see Note 3.

General Information

• Status: Historical
• Publication Date: 31-Mar-2008
• ICS: 71.040.30 - Chemical reagents
• Technical Committee: D32 - Catalysts
• Drafting Committee: D32.01 - Physical-Chemical Properties

Relations

• Replaces: ASTM D4365-95(2007)e1 - Standard Test Method for Determining Micropore Volume and Zeolite Area of a Catalyst
• Effective Date: 01-Apr-2008
• Referred By: ASTM D4463/D4463M-19 - Standard Guide for Metals Free Steam Deactivation of Fresh Fluid Cracking Catalysts
• Effective Date: 01-Apr-2008

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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
Designation: D4365 − 95(Reapproved 2008)
Standard Test Method for
Determining Micropore Volume and Zeolite Area of a
1
Catalyst
This standard is issued under the fixed designation D4365; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.1 mesopore area of a catalyst—the area determined
from the slope of the t-plot.
1.1 This test method covers the determination of total
surface area and mesopore area. From these results are calcu-
3.1.2 micropore volume of the catalyst—the pore volume in
lated the zeolite area and micropore volume of a zeolite
pores having radii less than 1 nm, usually associated with the
containing catalyst. The micropore volume is related to the
zeolite portion of the catalyst, and determined from the
percent zeolite in the catalyst. The zeolite area, a number
intercept of the t-plot.
relatedtothesurfaceareawithinthezeolitepores,mayalsobe
3.1.3 surface area of a catalyst—the total surface of the
calculated. Zeolite area, however, is difficult to intepret in
catalyst pores. It is expressed in square metres per gram.
physical terms because of the manner in which nitrogen
3.1.4 zeoliteareaofacatalyst—thedifferencebetweentotal
molecules pack within the zeolite.
surface area and mesopore area.
1.2 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the 3.2 Symbols:
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
P = initial helium pressure, torr
H
bility of regulatory limitations prior to use. For a specific 1
P = helium pressure after equilibration, torr
H
precautionary statement, see Note 3. 2
S = slope of BET plot, 11.7
B
I = intercept of BET plot, 11.7
B
2. Referenced Documents
S = slope of t-plot, 11.13
t
2
2.1 ASTM Standards:
I = intercept of t-plot, 11.13
t
D3663Test Method for Surface Area of Catalysts and
T = temperatureofmanifoldatinitialheliumpressure,
H1
Catalyst Carriers
°C
D3906Test Method for Determination of Relative X-ray
T = temperature of manifold after equilibration, °C
H2
Diffraction Intensities of Faujasite-Type Zeolite- T `(i) = extra volume bulb temperature, °C
x
T (i) = extra volume bulb temperature, K
Containing Materials
x
P (i) = initial N pressure, torr
E177Practice for Use of the Terms Precision and Bias in 1 2
T (i) = manifold temperature at initial N pressure, K
ASTM Test Methods 1 2
T `(i) = manifold temperature at initial N pressure, °C
1 2
E456Terminology Relating to Quality and Statistics
P (i) = pressure after equilibration, torr
2
E691Practice for Conducting an Interlaboratory Study to
T (i) = manifold temperature after equilibration, K
2
Determine the Precision of a Test Method
T `(i) = manifold temperature after equilibration, °C
2
P (i) = liquid nitrogen vapor pressure, torr
0
3. Terminology
T (i) = liquid nitrogen temperature, K
s
3.1 Definitions of Terms Specific to This Standard:
X = relative pressure, P /P
2 0
3
V = volume of manifold, cm
d
3
V = extra volume bulb, cm
x
3
1
This test method is under the jurisdiction of ASTM Committee D32 on
V = effective void volume, cm
s
Catalysts and is the direct responsibility of Subcommittee D32.01 on Physical-
W = weight of sample, g
s
Chemical Properties.
W = tare weight of sample tube, g
1
Current edition approved April 1, 2008. Published May 2008. Originally
ϵ1 W = weight of sample+tare weight of tube, g
2
approved in 1984. Last previous edition approved in 2007 as D4365–95(2007) .
3
V = volume of nitrogen in the dead-space, cm
DOI: 10.1520/D4365-95R08.
ds
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
V = see 11.4.3
1
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
V = see 11.4.4
2
Standards volume information, refer to the standard’s Document Summary page on
V = see 11.4.5
t
the ASTM website.
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1

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D4365 − 95 (2008)
FIG. 1 Schematic Diagram of Surface Area Apparatus
NOTE 1—See, for example, the article by Joy for a description of a
V = see 11.4.7
a
3
constant-volume manometer.
V = see 11.8
m
6.1.4 Valve (H), from the helium supply to the distribution
BET(i) = see 11.4.8
t(i) = see 11.10
manifold.
6.1.5 Value (N), from the nitrogen supply to the distribution
4. Summary of Test Method manifold.
6.1.6 The connection between the sample tube and the S
4.1 The volume of nitrogen gas adsorbed by the catalyst at
valve can be a standard-taper glass
...