ASTM D4222-20

Standard Test Method for Determination of Nitrogen Adsorption and Desorption Isotherms of Catalysts and Catalyst Carriers by Static Volumetric Measurements

SIGNIFICANCE AND USE
5.1 The test method has two main functions: first, it provides data useful for establishing the pore size distribution of catalyst materials, which in turn may influence their performance; and second, it serves as a laboratory test which may be used to study porosity changes that may occur during the manufacture and evaluation of catalysts.
SCOPE
1.1 This test method covers the determination of nitrogen adsorption and desorption isotherms of catalysts and catalyst carriers at the boiling point of liquid nitrogen.2 A static volumetric measuring system is used to obtain sufficient equilibrium adsorption points on each branch of the isotherm to adequately define the adsorption and desorption branches of the isotherm. Thirty points evenly spread over the isotherm is considered to be the minimum number of points that will adequately define the isotherm.  
1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Sep-2020
• ICS: 17.060 - Measurement of volume, mass, density, viscosity
• ICS: 71.040.30 - Chemical reagents
• Technical Committee: D32 - Catalysts
• Drafting Committee: D32.01 - Physical-Chemical Properties

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D4222 − 20
Standard Test Method for
Determination of Nitrogen Adsorption and Desorption
Isotherms of Catalysts and Catalyst Carriers by Static
1
Volumetric Measurements
This standard is issued under the fixed designation D4222; 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 D3766Terminology Relating to Catalysts and Catalysis
E177Practice for Use of the Terms Precision and Bias in
1.1 This test method covers the determination of nitrogen
ASTM Test Methods
adsorption and desorption isotherms of catalysts and catalyst
2 E456Terminology Relating to Quality and Statistics
carriers at the boiling point of liquid nitrogen. A static
E691Practice for Conducting an Interlaboratory Study to
volumetric measuring system is used to obtain sufficient
Determine the Precision of a Test Method
equilibriumadsorptionpointsoneachbranchoftheisothermto
adequately define the adsorption and desorption branches of
3. Terminology
the isotherm. Thirty points evenly spread over the isotherm is
3.1 Definitions—See Terminology D3766.
considered to be the minimum number of points that will
adequately define the isotherm. 3.2 Symbols:
1.2 Units—The values stated in SI units are to be regarded
as standard. The values given in parentheses after SI units are
PH = initial helium pressure, torr.
1
providedforinformationonlyandarenotconsideredstandard.
PH = helium pressure after equilibration, torr.
2
TH = temperature of manifold at initial helium pressure,
1.3 This standard does not purport to address all of the
1
°C.
safety concerns, if any, associated with its use. It is the
TH = temperature of manifold after equilibration, °C.
responsibility of the user of this standard to establish appro-
2
P = initial N pressure, torr.
1 2
priate safety, health, and environmental practices and deter-
T = manifold temperature at initial N pressure, K.
1 2
mine the applicability of regulatory limitations prior to use.
T' = manifold temperature at initial N pressure, °C.
1 2
1.4 This international standard was developed in accor-
P = pressure after equilibration, torr.
2
dance with internationally recognized principles on standard-
T = manifold temperature after equilibrrium, K.
2
ization established in the Decision on Principles for the
T' = manifold temperature after equilibrium, °C.
2
Development of International Standards, Guides and Recom-
P = initial N pressure during desorption, torr.
3 2
mendations issued by the World Trade Organization Technical
T = manifold temperature at initial N pressure, K.
3 2
Barriers to Trade (TBT) Committee.
T' = manifold temperature at initial N pressure, °C.
3 2
P = pressure after equilibration during desorption, torr.
4
2. Referenced Documents
T = manifold temperature after equilibration, K.
4
3
T' = manifold temperature after equilibration, °C.
2.1 ASTM Standards:
4
P = liquid nitrogen vapor pressure, torr.
D3663Test Method for Surface Area of Catalysts and 0
T = liquid nitrogen temperature, K.
Catalyst Carriers s
X = relative pressure, P /P .
2(4) 0
3
V = volume of manifold, cm .
d
3
1 V = the dead-space volume factor, cm (STP)/torr.
This test method is under the jurisdiction of ASTM Committee D32 on s
W = mass of sample, g.
Catalysts and is the direct responsibility of Subcommittee D32.01 on Physical-
s
Chemical Properties.
W = tare of sample tube, g.
1
Current edition approved Oct. 1, 2020. Published November 2020. Originally
W' = sample mass + tare of tube after degassing, g.
2
ε1
approved in 1983. Last previous edition approved in 2015 as D4222–03(2015) .
W = sample mass + tare of tube after adsorption, g.
2
DOI: 10.1520/D4222-20.
3
V = volume of nitrogen in the dead-space, cm (STP).
2
Adamson,A. W., Physical Chemistry of Surfaces, 3rd ed., John Wiley & Sons, ds
V = see 12.4.3.
New York, NY, 1976, p. 532.
1
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
V = see 12.4.4.
2
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
V = see 12.4.5.
t
Standards volume information, refer to the standard’s Document Summary page on
V = see 12.4.7.
ad
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D4222 − 20
6.1.1 Distribution Manifold, having a (V ), known to the
d
3
nearest 0.05 cm . This volume is defined as the volume
between the stopcocks or valves and i
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation: D4222 − 03 (Reapproved 2015) D4222 − 20
Standard Test Method for
Determination of Nitrogen Adsorption and Desorption
Isotherms of Catalysts and Catalyst Carriers by Static
1
Volumetric Measurements
This standard is issued under the fixed designation D4222; 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
ε NOTE—Eq 10 in subsection 12.4.7 was corrected editorially in August 2015.
1. Scope
1.1 This test method covers the determination of nitrogen adsorption and desorption isotherms of catalysts and catalyst carriers
2
at the boiling point of liquid nitrogen. A static volumetric measuring system is used to obtain sufficient equilibrium adsorption
points on each branch of the isotherm to adequately define the adsorption and desorption branches of the isotherm. Thirty points
evenly spread over the isotherm is considered to be the minimum number of points that will adequately define the isotherm.
1.2 Units—The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information
only.after SI units are provided for information only and are not considered standard.
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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
3
2.1 ASTM Standards:
D3663 Test Method for Surface Area of Catalysts and Catalyst Carriers
D3766 Terminology Relating to Catalysts and Catalysis
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E456 Terminology Relating to Quality and Statistics
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions—See Terminology D3766.
1
This test method is under the jurisdiction of ASTM Committee D32 on Catalysts and is the direct responsibility of Subcommittee D32.01 on Physical-Chemical
Properties.
Current edition approved April 1, 2015Oct. 1, 2020. Published August 2015November 2020. Originally approved in 1983. Last previous edition approved in 20082015
ε1
as D4222 – 03 (2008).(2015) . DOI: 10.1520/D4222-03R15.10.1520/D4222-20.
2
Adamson, A. W., Physical Chemistry of Surfaces, 3rd ed., John Wiley & Sons, New York, NY, 1976, p. 532.
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. 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
1

---------------------- Page: 1 ----------------------
D4222 − 20
3.2 Symbols:
PH = initial helium pressure, torr.
1
PH = helium pressure after equilibration, torr.
2
TH = temperature of manifold at initial helium pressure, °C.
1
TH = temperature of manifold after equilibration, °C.
2
P = initial N pressure, torr.
1 2
T = manifold temperature at initial N pressure, K.
1 2
T' = manifold temperature at initial N pressure, °C.
1 2
P = pressure after equilibration, torr.
2
T = manifold temperature after equilibrrium, K.
2
T' = manifold temperature after equilibrium, °C.
2
P = initial N pressure during desorption, torr.
3 2
T = manifold temperature at initial N pressure, K.
3 2
T' = manifold temperature at initial N pressure, °C.
3 2
P = pressure after equilibration during desorption, torr.
4
T = manifold temperature after equilibration, K.
4
T' = manifold temperature after equilibration, °C.
4
P = liquid nitrogen vapor pressure, torr.
0
T = liquid nitrogen temperature, K.
s
X = relative pressure, P /P .
2(4) 0
3
V = volume of manifold, cm .
d
3
V = the dead-space volume factor, cm (STP)/torr.
s
W = mass of sample, g.
s
W = tare of sample tube, g.
1
W' = sample mass + tare of tube after degas
...