ASTM D4463-96
(Guide)Standard Guide for Metals Free Steam Deactivation of Fresh Fluid Cracking Catalysts
Standard Guide for Metals Free Steam Deactivation of Fresh Fluid Cracking Catalysts
SCOPE
1.1 This guide covers the deactivation of fresh fluid catalytic cracking (FCC) catalyst by hydrothermal treatment prior to the determination of the catalytic cracking activity in the microactivity test (MAT).
1.2 The hydrothermal treatment of fresh FCC catalyst, prior to the MAT, is important because the catalytic activity of the catalyst in its fresh state is an inadequate measure of its true commercial performance. During operation in a commercial cracking unit, the catalyst is deactivated by thermal, hydrothermal and chemical degradation. Therefore, to maintain catalytic activity, fresh catalyst is added (semi) continuously to the cracking unit, to replace catalyst lost through the stack or by withdrawal, or both. Under steady state conditions, the catalyst inventory of the unit is called" equilibrium catalyst;" this catalyst has an activity level substantially below that of fresh catalyst. Therefore, artificially deactivating a fresh catalyst prior to determination of its cracking activity should provide more meaningful catalyst performance data.
1.3 Due to the large variations in properties among fresh FCC catalyst types as well as between commercial cracking unit designs and/or operating conditions, no single set of steam deactivation conditions is adequate to artificially simulate the equilibrium catalyst for all purposes.
1.3.1 In addition, there are many other factors that will influence the properties and performance of the equilibrium catalyst. These include, but are not limited to: deposition of heavy metals such as Ni, V, Cu; deposition of light metals such as Na; contamination from attrited refractory linings of vessel walls. Furthermore, commercially derived equilibrium catalyst represents a distribution of catalysts of different ages (from fresh to > 300 days). Despite these apparent problems, it is possible to obtain reasonably close agreement between the performance of steam deactivated and equilibrium catalysts. It is also recognized that it is possible to steam deactivate a catalyst so that its properties and performance poorly represent the equilibrium. It is therefore recommended that when assessing the performance of different catalyst types, a common steaming condition be used. Catalyst deactivation by metals deposition is not addressed in this guide.
1.4 This guide offers two approaches to steam deactivate fresh catalysts. The first part provides specific sets of conditions (time, temperature and steam pressure) that can be used as general pre-treatments prior to comparison of fresh FCC catalyst MAT activities (Test Method D 3907) and selectivities.
1.4.1 The second part provides guidance on how to pretreat catalysts to simulate their deactivation in a specific FCCU and suggests catalyst properties which can be used to judge adequacy of the simulation. This technique is especially useful when examining how different types of catalyst may perform in a specific FCCU, provided no other changes (catalyst addition rate, regenerator temperature, contaminant metals levels, etc.) occur. This approach covers catalyst physical properties that can be used as monitors to indicate the closeness to equilibrium catalyst properties.
1.5 The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information only.
1.6 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./p>
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Designation: D 4463 – 96
Standard Guide for
Metals Free Steam Deactivation of Fresh Fluid Cracking
Catalysts
This standard is issued under the fixed designation D 4463; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope steaming condition be used. Catalyst deactivation by metals
deposition is not addressed in this guide.
1.1 This guide covers the deactivation of fresh fluid cata-
1.4 This guide offers two approaches to steam deactivate
lytic cracking (FCC) catalyst by hydrothermal treatment prior
fresh catalysts. The first part provides specific sets of condi-
to the determination of the catalytic cracking activity in the
tions (time, temperature and steam pressure) that can be used
microactivity test (MAT).
as general pre-treatments prior to comparison of fresh FCC
1.2 The hydrothermal treatment of fresh FCC catalyst, prior
catalyst MAT activities (Test Method D 3907) and selectivities.
to the MAT, is important because the catalytic activity of the
1.4.1 The second part provides guidance on how to pretreat
catalyst in its fresh state is an inadequate measure of its true
catalysts to simulate their deactivation in a specific FCCU and
commercial performance. During operation in a commercial
suggests catalyst properties which can be used to judge
cracking unit, the catalyst is deactivated by thermal, hydrother-
adequacy of the simulation. This technique is especially useful
mal and chemical degradation. Therefore, to maintain catalytic
when examining how different types of catalyst may perform in
activity, fresh catalyst is added (semi) continuously to the
a specific FCCU, provided no other changes (catalyst addition
cracking unit, to replace catalyst lost through the stack or by
rate, regenerator temperature, contaminant metals levels, etc.)
withdrawal, or both. Under steady state conditions, the catalyst
occur. This approach covers catalyst physical properties that
inventory of the unit is called“ equilibrium catalyst;” this
can be used as monitors to indicate the closeness to equilibrium
catalyst has an activity level substantially below that of fresh
catalyst properties.
catalyst. Therefore, artificially deactivating a fresh catalyst
1.5 The values stated in SI units are to be regarded as
prior to determination of its cracking activity should provide
standard. The values given in parentheses are provided for
more meaningful catalyst performance data.
information only.
1.3 Due to the large variations in properties among fresh
1.6 This standard does not purport to address all of the
FCC catalyst types as well as between commercial cracking
safety concerns, if any, associated with its use. It is the
unit designs and/or operating conditions, no single set of steam
responsibility of the user of this standard to establish appro-
deactivation conditions is adequate to artificially simulate the
priate safety and health practices and determine the applica-
equilibrium catalyst for all purposes.
bility of regulatory limitations prior to use.
1.3.1 In addition, there are many other factors that will
influence the properties and performance of the equilibrium
2. Referenced Documents
catalyst. These include, but are not limited to: deposition of
2.1 ASTM Standards:
heavy metals such as Ni, V, Cu; deposition of light metals such
D 3663 Test Method for Surface Area of Catalysts
as Na; contamination from attrited refractory linings of vessel
D 3907 Test Method for Testing Fluid Catalytic Cracking
walls. Furthermore, commercially derived equilibrium catalyst
(FCC) Catalysts by Microactivity Test
represents a distribution of catalysts of different ages (from
D 3942 Test Method for Determination of the Unit Cell
fresh to > 300 days). Despite these apparent problems, it is
Dimension of a Faujasite-Type Zeolite
possible to obtain reasonably close agreement between the
D 4365 Test Method for Determining Micropore Volume
performance of steam deactivated and equilibrium catalysts. It
and Zeolite Area of a Catalyst
is also recognized that it is possible to steam deactivate a
D 5154 Test Method for Determining the Activity and
catalyst so that its properties and performance poorly represent
Selectivity of Fluid Catalytic Cracking (FCC) Catalysts by
the equilibrium. It is therefore recommended that when assess-
Microactivity Test
ing the performance of different catalyst types, a common
E 105 Practice for Probability Sampling of Materials
E 177 Practice for Use of the Terms Precision and Bias in
This guide is under the jurisdiction of ASTM Committee D-32 on Catalysts and
is the direct responsibility of Subcommittee D32.04 on Catalytic Properties.
Current edition approved March 10, 1996. Published May 1996. Originally Annual Book of ASTM Standards, Vol 05.03.
published as D 4463 – 85. Last previous edition D 4463 – 91. Annual Book of ASTM Standards, Vol 14.02.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 4463
ASTM Test Methods 8. Procedure
E 456 Terminology Relating to Quality and Statistics
8.1 Procedure for fluid bed and fixed bed steam treatment
E 691 Practice for Conducting an Interlaboratory Study to
(non-shock steaming):
Determine the Precision of a Test Method
8.1.1 With the reactor heated to 300°C (572°F) or lower,
load the reactor with catalyst.
3. Summary of Guide
8.1.2 Start nitrogen flow to the reactor at a flow velocity of
3.1 A sample of fresh fluid cracking catalyst is placed in a
3 cm/s (0.1 ft/s).
reactor, either fixed bed or preferably in a fluid bed, and is
8.1.3 Heat the reactor at the maximum rate until a tempera-
contacted with steam at elevated temperature. This treatment
ture of 600°C (1112°F) is reached.
causes partial deactivation of the catalyst.
8.1.4 Keep the temperature constant at 600°C (1112°F) for
30 min in order to remove volatile material from the catalyst.
NOTE 1—In a fixed bed reactor, material containing sulfates, chlorides,
etc. can result in significant additional chemical deactivation. 8.1.5 Heat the reactor at the maximum rate until the desired
steaming temperature is reached; for example, at 760, 788 or
3.2 The catalyst is withdrawn from the reactor and may be
800°C (1400, 1450 or 1472°F) 6 2°C (6 3.6°F).
subjected to an activity or selectivity determination, or both, by
8.1.6 Stop the nitrogen flow and start a flow of undiluted
using the microactivity test. (Methods D 3907 or D 5154, or
steam at atmospheric pressure and at constant temperature
both.)
(760, 788 or 800°C). Continue this steam flow for 5 hours. For
4. Significance and Use fixed bed operation, keep the steam flow velocity at 5 6 1 cm/s
(0.16 6 0.03 ft/s) at the desired deactivation temperature. For
4.1 In general, steam treatment of FCC catalyst can be used
fluid bed operation, keep the steam velocity at 3 6 1 cm/s (0.10
either to compare a series of cracking catalysts at a simulated
6 0.03 ft/s).
equilibrium condition or conditions, or to simulate the equilib-
8.1.7 After 5 h, stop the steam flow and start nitrogen
rium condition of a specific cracking unit and a specific
flowing at 3 cm/s (0.10 ft/s) through the reactor.
catalyst. This guide gives an example for the first purpose and
8.1.8 Cool down the reactor to less than 300°C (572°F). The
an approach for the latter purpose.
rate of cooling is not critical.
5. Apparatus
8.1.9 Remove the catalyst from the reactor and store in a
sealed bottle.
5.1 Fixed bed or fluid bed steaming reactors can be used for
8.2 Variations in this procedure in which predried catalyst is
the hydrothermal treatment of FCC catalyst.
added to a steaming reactor preheated to the desired steaming
5.2 In the steaming reactor, temperatures of the catalyst can
temperature (shock steaming) are also permissible provided a
be maintained at
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