Note: Descriptions are shown in the official language in which they were submitted.
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PALLADIUM-GOLD CATALYST FOR VINYL AC1JTATE PRODUCTION
BACKGROUND OF THE INVENTION
This invention relates to a novel process for the preparation of a palladium-
gold catalyst
with improved selectivity in vinyl acetate production.
A well-known commercial process for the production of vinyl acetate is by the
gas phase
reaction of ethylene, acetic acid and oxygen in the presence of a supported
catalyst which
contains palladium.
A preferred type of vinyl acetate catalyst is one having a content of
palladium metal and
1~0 gold metal distributed on the surface of a support substrate such as
silica or alumina.
Prior art references which describe supported palladium-gold catalysts for
vinyl acetate
production include United States Patent Numbers 3,761,513; 3,775,342;,
3,822,308; 3,939,199;
4,048,096; 4,087,622; 4,133,962; 4,902,8?3; 5,179,056; 5,179,057; $.194,417;
5,314,858;
5,332,710..
A standard process for preparing a vinyl acetate catalyst containing palladium
and gold
deposited on a catalyst support medium comprises
(1) impregnating the support with an aqueous solution of water-soluble
palladium and gold
compounds, (2) precipitating and fixing water-insoluble palladium and gold
compounds on the
catalyst support by contacting the impregnated catalyst support with an
aqueous alkaline solution
capable of reacting with the water-soluble palladium and gold compounds to
form the water-
insoluble precious metal compounds, (3) washing the treated catalyst with
water to remove
anions which are freed from the initially impregnated palladium and gold
compounds during
precipitation, and (4) converting the water-insoluble palladium and gold
compounds to the free
metal state by treatment with a reducing agent. An optional final procedure
usually involves (5)
impregnating the reduced catalyst with an aqueous alkali metal alkanoate
solution, and drying
the final catalyst product.
The activity and selectivity properties of a supported palladium-gold catalyst
are affected
by the physicochemical form of the palladium and gold metal content on the
catalyst support
substrate.
U.S. 4,048,096 describes a catalyst which consists of a palladium-gold alloy
distributed
as a shell coating on the exterior surface area of a catalyst support such as
porous silica. The
shell distribution of palladium-gold alloy provides an improved space-time-
yield activity in a
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vapor phase reaction of ethylene, acetic acid and oxygen for vinyl acetate
production.
The selectivity of a palladium-gold catalyst in vinyl acetate synthesis also
is influenced
by the extent and uniformity of the palladium metal and gold metal
distribution on the exterior
and/or interior surfaces of a porous catalyst support substrate, such as
carbon dioxide selectivity
S and oxygen conversion in an ethylene, acetic acid and oxygen vapor phase
reaction.
Attempts to provide a uniform distribution of the palladium and gold metals on
the
catalyst support has involved manipulation of the catalyst preparation steps
and/or by using
support substrates having various specified pore dimensions. Particularly
useful improvements
in preparing highly active catalysts for vinyl acetate production are
disclosed in U.S. 5,314,858
and U.S. 5,332,710. These references describe process embodiments for
improving palladium
and gold distribution on a support by manipulating the precipitation step in
which the water-
soluble precious metal compounds are fixed to the support surface as water-
insoluble
compounds. In U.S. 5,314,858, fixing precious metals on the support is
achieved utilizing two
separate precipitation stages to avoid using large excesses of fixing agent.
U.S. 5,332,710
describes flxtIlg the precious metals by physically rotating an impregnated
catalyst support while
the impregnated support is immersed in a reaction solution at least during the
initial precipitation
period. The novel rotation immersion procedure yields catalysts in which the
precipitated carrier
metals are more evenly distributed in a thin shell on the support surface.
The prior art has addressed other physicochemical aspects that affect the
properties of
palladium gold catalysts which are adapted for vinyl acetate production.
U.S. 5,179,056 and U.S. 5,179,057 are related references which are directed to
the
improvement palladium-gold catalysts for vinyl acetate production from
ethylene, acetic acid
and oxygen. The described invention catalysts have increased activity because
of a reduced
sodium content.
In a preferred catalyst preparation embodiment of the two references, the
sodium content
of a supported palladium-gold is reduced during catalyst preparation by
washing the palladium
and gold metal-containing support medium with an ion-exchange aqueous solution
of a
potassium compound. In the catalyst preparation processes of the two
references, the use of
precious metal sodium salt compounds is permitted, such as sodium palladium
tetrachlorate
(Na~PdCla). The added sodium content in the precious metal-treated catalyst
support substrate
subsequently is removed by washing with an aqueous ion-exchange solution.
There is a continuing interest in the development of catalyst compositions
which exhibit
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an improved combination of properties for the production of
vinyl acetate.
SUMMARY OF THE INVENTION
This invention provides a supported palladium-gold
catalyst composition with improved carbon dioxide
selectivity in vinyl acetate production from ethylene,
acetic acid and oxygen. This invention also provides a
supported vinyl acetate catalyst which is essentially
sodium-free, and is characterized by a thin palladium-gold
metal shell coating on the support surface. Further, this
invention provides a process for preparation of a supported
palladium-gold catalyst for vinyl acetate production from
ethylene, acetic acid and oxygen, in which process all of
the catalyst support-impregnating reactants are essentially
sodium-free potassium salt compounds.
In one aspect, the invention provides a process
for the preparation of a catalyst for production of vinyl
acetate from ethylene, acetic acid and oxygen, which process
comprises (1) impregnating a porous catalyst support medium
with an aqueous solution consisting of a water-soluble
potassium-palladium compound and a water-soluble potassium-
gold compound; (2) precipitating water-insoluble palladium
and gold compounds onto the catalyst support surfaces with
an aqueous solution of a basic potassium salt fixing agent;
and (3) reducing the water-insoluble palladium and gold
compounds to palladium metal and gold metal to form a
catalyst with improved carbon dioxide selectivity, wherein
the catalyst product has a palladium metal content between
about 0.4-2.5 weight percent, and a gold metal content
between about 0.1-1.0 weight percent, based on the catalyst
weight, and wherein the catalyst product has a
palladium: gold weight ratio between about 1-10:1.
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Other aspects and advantages of the present
invention shall become apparent from the accompanying
description and examples.
DESCRIPTION OF THE INVENTION
One or more aspects of the present invention are
accomplished by the provision of a process for the
preparation of a catalyst for production of vinyl acetate
from ethylene, acetic acid and oxygen, which process
comprises (1) impregnating a porous catalyst support medium
with an aqueous solution of water-soluble potassium-
palladium compound and water-soluble potassium-gold
compound; (2) precipitating water-insoluble palladium and
gold compounds onto the catalyst support surface with an
aqueous solution of basic potassium salt fixing agent; and
(3) reducing the water-insoluble palladium and gold
compounds to palladium metal and gold metal to form a
catalyst with improved carbon dioxide selectivity.
The catalyst support medium is selected from
porous substrates such as silica, alumina, silica/alumina,
or titania, in the form of spheres, tablets, Raschig rings,
and the like. For purposes of the present invention, it is
preferred that the support medium has little or no content
of sodium, i.e., a sodium content less than about 0.1 weight
percent of the support medium.
A typical catalyst support medium is illustrated
by porous silica spheres which have a radius of 1-8 mm, a
pore volume of 0.1-2 cc/g, and an internal surface area of
10-350 m2/g. Commercial catalyst support media are widely
available, such as porous 5 mm silica spheres sold under the
tradename KA-160 by Sud-Chemie.
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In one method of preparing the improved vinyl acetate catalyst of the present
invention,
the catalyst support first is impregnated with an aqueous solution of water-
soluble potassium-
palladium compound and potassium-gold compound. Suitable water-soluble
palladium and gold
compounds are illustrated by potassium palladium tetrachlorate (K,PdCI,) and
potassium
tetrachloroaurate (KAuCI,).
The volume of the aqueous impregnating solution preferably is between about 95-
100%
of the absorptive capacity of the catalyst support, which is characterized as
an "incipient
wetness" technique. As an alternative procedure, the water-soluble potassium-
palladium
compound and the potassium gold compound respectively can be impregnated on
the support
,10, successively in separate aqueous solutions.
In step (2) of the invention process, in accordance with a standard method the
impregnated catalyst support is treated with an aqueous solution of a basic
potassium salt, such
as potassium silicate, potassium carbonate or potassium hydroxide. The
treatment with basic
potassium salt solution fixes the palladium and gold compounds on the catalyst
support, i.e.,
palladium hydroxide and gold hydroxide are precipitated and are incorporated
onto the catalyst
support surface.
The amount of basic potassium salt fixing agent employed in step (2) of the
invention
process is such that the ratio of potassium metal to anions from the water-
soluble precious metal
compounds is from about I :1 to about 2:1, preferably from about 1.2:1 to
about 1.8:1. By
treatment with the basic potassium salt solution, the precious metal water-
soluble compounds are
converted_to water-insoluble compounds which mainly appear to be hydroxides
and/or oxides.
Another method of palladium and gold fixing agents as insoluble compounds on
the
impregnated support in step (2) of the invention process is disclosed in U.S.
5;332,710
and is described as a "rotation immersion" process.
In this alternative fixing procedure, the impregnated support from step ( 1 )
is immersed in
the basic potassium salt solution and rotated or tumbled therein during the
initial stages of the
precipitation of the water-insoluble precious metal compounds.. The rotation
or tumbling of the
support in the alkaline fixing solution preferably proceeds for at least about
0.5 hour upon the
initial treatment and most preferably for at least about 2.5 hours. The
rotation immersion
treatment can be conducted up to about 4 hours before the treated support
medium is allowed to
stand in the fixing solution to insure that precipitation of the precious
metal compounds is
complete.
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Any type of rotation or tumbling equipment can be utilized which provides a
rotation
action that is effective for contacting all of the support surfaces evenly
with the basic potassium
salt solution. The rotation action preferably is sufficiently gentle to
prevent permanent loss of
water-insoluble palladium and gold compounds from the catalyst support surface
by abrasion.
The rotation immersion method is effective for achieving a thin shell coating
of
palladium and gold metals on the catalyst support surface with a controlled
degree of thickness,
e.g., a shell thickness between about 0.1-0.5 millimeters. For purposes of the
present invention,
a thin shell coating of palladium-gold metals on a catalyst support surface
contributes to the
improvement of carbon dioxide selectivity in vinyl acetate production from
ethylene, acetic acid
and oxygen.
Another fixing procedure in step (2) of the invention process is by an
"incipient wetness"
method. In this technique, a specific volume of aqueous basic potassium salt
solution, equal to
the absorptivity of the air-dried catalyst support medium from step ( 1 ) is
applied to the support
medium. The reactive admixture is allowed to stand until precipitation of the
insoluble
palladium and gold compounds is complete.
Another fixing procedure for step (2) of the invention process is described in
U.S. 5,314,858. In this method, the step (2) fixing procedure is
divided into at least two separate stages of support treatment with aqueous
basic potassium salt
solution.
Subsequent to the invention process step(2), the fixing stage by any of the
methods
described above, step (3) is performed. In step (3) the fixed support medium
is washed
repeatedly with deionized water.to remove anions (e.g., chloride ions) which
have been
introduced by the impregnating solution in step ( 1 ) of the invention
process. After the catalyst
support medium is washed completely free of the anions, the catalyst is dried
at a temperature up
to about 150°C under an inert atmosphere.
After the step (3) treatment is completed, in step (4) the catalyst support is
contacted with
a reducing agent to convert the fixed palladium and gold compounds into a
shell coating of
palladium and gold metal particles on the catalyst support surface.
Illustrative of reducing
agents are hydrazine, formaldehyde, ethylene, hydrogen, and the like.
If the reduction is performed with a solution of hydrazine hydrate, the
reaction normally
is conducted at.ambient temperature. Vi~hen the reduction is conducted in the
gas phase with
ethylene or hydrogen, it is advantageous to perform the reaction at an
elevated temperature
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between about 100°-200°C. The reducing agent preferably is
employed in excess to assure the
complete conversion of the water-insoluble palladium and gold compounds into
the free metal
form. When hydrazine is employed, the weight ratio of hydrazine to precious
metals ranges
from about 10:1 to about 15:1. After the water-insoluble palladium and gold
compounds have
S been reduced, the catalyst support is dried in an inert atmosphere at about
150°C.
Optionally, the present invention process for catalyst preparation can include
an
additional procedure (step (5)) to enhance the selectivity of the catalyst in
vinyl acetate
production. The palladium-gold catalyst obtained by the above-described
process is treated with
an aqueous solution of potassium alkanoate, and then dried. The potassium
alkanoate content
can be in the range between about 2-10 weight percent, based on the weight of
the finished
catalyst. Suitable potassium alkanoates include the potassium salt of formic
acid, acetic acid,
propionic acid, butyric acid, and the like.
Typically a present invention catalyst is employed in a vinyl acetate process
by
contacting ethylene, acetic acid and oxygen or air with a catalyst at
temperatures between about
100°-200°C and a pressure between about 1-10 atmospheres. The
reaction usually is conducted
with an excess of ethylene.
A present invention catalyst is characterized by a high level of palladium
metal and gold
metal retention, and exhibits improved selectivity in vinyl acetate production
from ethylene,
acetic acid and oxygen.
A present invention catalyst can provide efficient production of vinyl
acetate, with a
lower yield of carbon dioxide than conventional commercial-type vinyl acetate
catalysts. The
beneficial selectivity properties of the invention catalyst are attributable
to the unique features of
the present invention process for catalyst preparation, i.e., the exclusive
use of sodium-free
potassium salt derivatives in all the catalyst support impregnation steps.
The following examples are further illustrative of the present invention. The
components
and specific ingredients are presented as being typical, and various modif
canons can be derived
in view of the foregoing disclosure within the scope of the invention.
The Vinyl Acetate Stirred Tank (VAST) Reactor in the Examples is a Berty
reactor, or a
continuous stirred tank reactor of the recirculating type that is run at
constant oxygen conversion
(about 45%). The catalyst (62 cc) is loaded in a basket in the reactor, a
measured amount of
acetic acid, ethylene, and oxygen is added in a nitrogen diluent, and the
reactor is brought up to
temperature by means of a heating mantle, and the temperature is measured
above and below the
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catalyst. The reaction is terminated after approximately 18 hours at a
temperature at which 45%
oxygen conversion is maintained. Products are measured by gas-phase
chromatography.
EXAMPLE I
This Example illustrates the preparation of a present invention Pd-Au catalyst
by a
standard method using potassium Pd-Au salts and potassium hydroxide as the
fixing agent, and
demonstrates the properties of the catalyst in the production of vinyl acetate
from ethylene,
acetic acid and oxygen in a VAST reactor system.
A 250 cc quantity of 5 mm silica spheres (KA-160, Sud Chemie) was impregnated
with
87.29 mL of aqueous solution (5.13 g K~PdCl4 and 1.46 g KAuCl4) to incipient
wetness. The
impregnated support was dried, and then treated with 87.29111L of aqueous
potassium hydroxide
solution (2.62 g KOH), and the treated silica support was allowed to stand for
about 16 hours.
The silica support was washed with water until a negative AgN03 text was
obtained.
The silica support was dried at 150°C for about 16 hours under a
nitrogen purge. The
dried support was reduced with 5% ethylene in nitrogen at 150°C for 5
hours. The reduced
support was impregnated with 10 g of KOAc in 87.29 mL of water, and the
resultant catalyst
was dried in a fluid bed drier at 100°C for one hour.
The Pd-Au catalyst as prepared had a weight content of 0.9% Pd, 0.32% Au, 8.2%
KOAc, and 945 ppm Cl.
The properties of the invention Pd-Au catalyst for vinyl acetate production
were
determined in a VAST reactor, as summarized in Table A (Catalyst I).
EXAMPLE II
This Example illustrates the preparation of a present invention Pd-Au catalyst
by a
standard method using potassium Pd-Au salts and potassium hydroxide fixing
agent, and
demonstrates the properties of the catalyst in the production of vinyl acetate
from ethylene,
acetic acid and oxygen in a VAST reactor system.
Following the standard procedure of Example I, K~PdCl4 (5.13 g), KAuCIa ( 1.45
g),
KOH (2.86 g) and KOAc (10 g) were employed.
After reduction with ethylene, the Pd-Au catalyst as prepared had a weight
content of
1.0% Pd, 0.41 % Au, 7.5% KOAc, and 1000 ppm Cl.
The properties of the invention Pd-Au catalyst for vinyl acetate production
were
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determined in a VAST reactor, as summarized in Table A (Catalyst II).
A long term ageing test (23 months) indicated that a present invention type of
all-
potassium catalyst maintained a high activity level, and exhibited a low long
term carbon
dioxide selectivity in vinyl acetate production in comparison with commercial
Pd-Au catalysts.
EXAMPLE III
This Example illustrates the preparation of a Pd-Au catalyst by a standard
method using
potassium Pd-Au salts and sodium hydroxide fixing agent, and demonstrates tile
properties of
the catalyst in the production of vinyl acetate from ethylene, acetic acid and
oxygen in a VAST
reactor system.
Following the standard procedure of Example I, K~PdCI~(5.13 g), KAuCIa ( 1.45
g),
NaOH (2.04 g) and KOAc ( 10 g) were employed.
After reduction with ethylene, the Pd-Au catalyst as prepared had a weight
content of
1.1% Pd, 0.46% Au, 7.7% KOAc, and 725 ppm C1.
The properties of the Pd-Au catalyst for vinyl acetate production were
determined in a
VAST reactor as summarized in Table A (Catalyst III).
EXAMPLE IV
This Example illustrates the preparation of a Pd-Au catalyst by a standard
method using
sodium Pd-Au salts and sodium hydroxide fixing agent, and demonstrates the
properties of the
catalyst in the production of vinyl acetate from ethylene, acetic acid and
oxygen in a VAST
reactor system.
Following the standard procedure of Example I, Na2PdCla (I .65 g Pd), NaAuCl4
(0.75 g
Au), NaOH (1.766 g), and KOAc (10 g) were employed.
After reduction with ethylene, the Pd-Au catalyst as prepared had a weight
content of
0.92% Pd, 0.38% Au, 7.98% ICOAc, and 750 ppm Cl.
The properties of the Pd-Au catalyst for vinyl acetate production were
determined in a
VAST reactor, as summarized in Table A (Catalyst IV).
EXAMPLE V
This Example illustrates the preparation of a Pd-Au catalyst by a standard
method using
sodium Pd-Au salts and sodium hydroxide fixing agent, and demonstrates the
properties of the
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catalyst in the production of vinyl acetate from ethylene, acetic acid and
oxygen in a VAST
reactor system.
Following the standard procedure of Example I, Na~PdCl4 (1.65 g Pd), NaAuCl4
(0.75 g
Au), NaOH (2.04 g), and KOAc ( 10 g) were employed.
After reduction with ethylene, the Pd-Au catalyst as prepared had a weight
content of
0.89% Pd, 0.46% Au, 7.5% KOAc, and 770 ppm Cl.
The properties of the Pd-Au catalyst for vinyl acetate production were
determined in a
VAST reactor, as summarized in Table A (Catalyst V).
EXAMPLE VI
This Example illustrates the preparation of a present invention Pd-Au catalyst
by a
standard method using potassium Pd-Au salts and potassium silicate fixing
agent, and
demonstrates the properties of the catalyst in the production of vinyl acetate
from ethylene,
acetic acid and oxygen in a VAST reactor system.
1 S Following the standard procedure of Example I, K,PdCl4 ( 1.65 g Pd),
KAuCl4 (0.75 g
Au), K~Si03 (2.0 g of K), and ICOAc ( 10 g) were employed.
After reduction with ethylene, the invention Pd-Au catalyst as prepared had a
weight
content of 1.0% Pd, 0.44% Au, 7.6% KOAc, and 66:5 ppm Cl.
The properties of the invention Pd-Au catalyst for vinyl acetate production
were
determined in a VAST reactor, as summarized in Table A (Catalyst VI}.
EXAMPLE VII
This Example illustrates the preparation of a Pd-Au catalyst by a standard
method using
sodium Pd-Au salts and potassium silicate fixing agent, and demonstrates the
properties of the
catalyst in the production of vinyl acetate from ethylene, acetic acid and
oxygen in a VAST
reactor system.
Following the standard procedure of Example I, Na,PdCl4 ( 1.65 g Pd), NaAuCl4
(0.75 g
Au), KZSi03 (2.0 g of IC), and KOAc (10 g) were employed.
After reduction with ethylene, the Pd-Au catalyst as prepared had a weight
content of
0.98% Pd, 0.42% Au, 7.2% KoAc, and 910 ppm Cl.
The properties of the Pd-Au catalyst for vinyl acetate production were
determined in a
VAST reactor, as summarized in Table A (Catalyst VII).
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EXAMPLE VIII
This Example illustrates the preparation of a Pd-Au catalyst by a standard
method using
sodium Pd-Au salts and sodium silicate fixing agent, and demonstrates the
properties of the
catalyst in the production of vinyl acetate from ethylene, acetic acid and
oxygen in a VAST
S reactor system.
Following the standard procedure of Example I, Na~PdCl4 (1.65 g Pd), NaAuCl4
{0.75 g
Au), Na~Si03 {7.23 g), and KOAc (10 g) were employed.
After reduction with ethylene, the Pd-Au catalyst as prepared had a weight
content of
1.0% Pd, 0.44% Au, 7.4% KOAc, and 765 ppm C1.
10 The properties of the Pd-Au catalyst for vinyl acetate production were
determined in a
VAST reactor, as summarized in Table A (Catalyst VIII).
EXAMPLE IX
This Example illustrates the preparation of a present invention Pd-Au catalyst
by a
rotation immersion method using potassium Pd-Au salts and potassium silicate
fixing agent, and
demonstrates the properties of the catalyst in the production of vinyl acetate
from ethylene,
acetic acid and oxygen in a VAST reactor system.
The procedure of Example I was followed to impregnate 5 mm silica spheres with
87.29
mL of aqueous solution (5.13 g K~PdCl4 and 1.46 g of KAuCI~) to incipient
wetness.
The impregnated support was treated with 300 mL of aqueous potassium silicate
solution
(2.0 g of K). Following the procedure described in U.S. 5,332,7/0, the treated
silica support was
transferred to a rotation immersion flask, and the flask was rotated for 2.5
hours. The silica
support then was washed until a negative AgN03 test was obtained.
The silica support was dried, and then reduced with 5% ethylene in nitrogen at
150°C for
5 hours. The reduced support was impregnated with 10 g of ICOAc in 87.29 mL of
water, and
the resultant invention catalyst was dried in a fluid-bed drier at
100°C for one hour.
The invention Pd-Au catalyst as prepared had a weight content of 0.83% Pd,
0.34% Au,
7.8% KOAc, and 430 ppm Cl.
The properties of the invention Pd-Au catalyst for vinyl acetate product were
determined
in a VAST reactor, as summarized in Table A (Catalyst IX).
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EXAMPLE X
This Example illustrates the preparation of a Pd-Au catalyst by a rotation
immersion
method using sodium Pd-Au salts and potassium silicate fixing agent, and
demonstrates the
properties of the catalyst in the production of vinyl acetate from ethylene,
acetic acid and oxygen
in a VAST reactor system.
Following the rotation immersion procedure of Example IX, Na2PdCl~ (1.65 g
Pd),
NaAuCl4 (0.75 g Au), K~Si03 (2.09 g of K), and KOAc (10 g) were employed.
After reduction with ethylene, the Pd-Au catalyst as prepared had a weight
content of
0.94% Pd, 0.19% Au, 7.5% KOAc, and 1165 ppm C1.
The properties of the Pd-Au catalyst for vinyl acetate production were
determined in a
VAST reactor, as summarized in Table A (Catalyst X).
The comparative data in Table A demonstrate; that a Pd-Au catalyst prepared
exclusively
with potassium-containing reactants exhibits lower carbon dioxide selectivity
in vinyl acetate
production, in comparison with a corresponding Pd-Au catalyst which is
prepared with one or
I S more sodium-containing reactants.
The comparative data in Table A also demonstrate that a Pd-Au catalyst with
potassium-
containing reactants including potassium silicate fixing agent such as
Catalyst IX, exhibits
exceptional carbon dioxide selectivity improvement in the vinyl acetate
process. The thin Pd-Au
shell coating in Catalyst IX is a contributing factor in the carbon dioxide
selectivity
improvement, as compared to the Pd-Au catalyst with a thicker Pd-Au shell on
the catalyst
surface. The rotation immersion procedure provides a thinner Pd-Au shell which
is beneficial
for improvement of carbon dioxide selectivity.
Other important advantages derive from the use of potassium silicate as a
fixing agent, in
comparison with the use of potassium hydroxide. Potassium silicate is a mildly
basic
compound, and does not attack a silica support medium as does a strongly basic
compound.
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'TABLE A
Pd-Au
ExamplePd-Au Caustic % Fixing Shell Se lectivity Relative
CatalystSalts Pd-Au Au Agent mm CO, tOAc HE ctivitv
Ratio E A
I Potassium0.96:1 0.32 KO 0.377 9.12 H 1.0 6 1.73
0.088
II Potassium1.04:1 0.41 ICOH 0.352 9.40 0.0971.272.00
III Potassium1.2:1 0.46 NaOH 0.409 9.95 0.0961.452.18
IV Sodium 1.04:1 0.38 NaOH N.A. 0.24 0.0731.021.81
V Sodium 1.2:1 0.46 NaOH 0.497 10.210.0841.202.05
VI Potassium1.2:1 0.44 IC,Si03 0.232 9.48 0.0931.432.16
VII Sodium 1.2:1 0.42 K~SiOj 0.216 11.450.0871.221.97
VIII Sodium 1.2:1 0.44 Na~Si03 0.419 10.600.0831.172.11
IX Potassium1.2:1 0.24 K~Si03 O.I29 8.13 0.1061.131.58
X Sodium 1.2:1 0.19 IC~Si03 0.103 9.67 0.0870.941.12
