Molecular sieve abstract
The present invention relates to new crystalline molecular sieve
SSZ-47B prepared using a N-cyclopentyl-14-diazabicyclo[2.2.2]octane
cation as a structure-directing agent and an amine too large to
fit in the pores of the molecular sieve nonasil, methods for synthesizing
SSZ-47B and processes employing SSZ-47B in a catalyst.
Molecular sieve claims
What is claimed is:
1. A molecular sieve having a composition, as synthesized and in
the anhydrous state, in terms of mole ratios as follows: TABLE-US-00009
YO.sub.2/W.sub.cO.sub.d >15 M.sub.2/n/YO.sub.2 0.01 0.03 Q/YO.sub.2
0.02 0.05 Amine/YO.sub.2 0.01 0.05
wherein Y is silicon, germanium or a mixture thereof; W is aluminum,
gallium, iron, boron, titanium, indium, vanadium or mixtures thereof,
c is 1 or 2; d is 2 when c is 1 or d is 3 or 5 when c is 2; M is
an alkali metal cation, alkaline earth metal cation or mixtures
thereof; n is the valence of M; Q is a N-cyclopentyl-14-diazabicyclo[2.2.2]octane
cation and Amine is an amine too large to fit in the pores of nonasil.
2. A molecular sieve according to claim 1 wherein the amine is
also small enough to fit in the pores of the molecular sieve.
3. A molecular sieve according to claim 1 wherein W is aluminum
and Y is silicon.
4. A molecular sieve according to claim 3 wherein the amine is
also small enough to fit in the pores of the molecular sieve.
5. A molecular sieve according to claim 1 wherein W is boron and
Y is silicon.
6. A molecular sieve according to claim 5 wherein the amine is
also small enough to fit in the pores of the molecular sieve.
7. A molecular sieve according to claim 1 2 3 4 5 or 6 wherein
the amine is 44'-trimethylene dipiperidine.
8. A method of preparing a crystalline material having, after calcination,
the X-ray diffraction lines of Table II comprising (1) an oxide
of a first tetravalent element and (2) an oxide of a trivalent element,
pentavalent element, second tetravalent element which is different
from said first tetravalent element or mixture thereof and having
a mole ratio of the first oxide to the second oxide greater than
15 said method comprising contacting under crystallization conditions
sources of said oxides, an N-cyclopentyl-14-diazabicyclo[2.2.2]octane
cation and an amine too large to fit in the pores of the molecular
sieve nonasil.
9. The method of claim 8 wherein the crystalline material has,
after calcination, a micropore volume of at least 0.10 cc/g.
10. The method of claim 8 wherein the crystalline material has,
after calcination, a Constraint Index of less than or equal to 2.0.
11. The method according to claim 8 wherein the first tetravalent
element is selected from the group consisting of silicon, germanium
and combinations thereof.
12. The method according to claim 11 wherein the first tetravalent
element is silicon.
13. The method according to claim 8 wherein the trivalent element,
pentavalent element or second tetravalent element is selected from
the group consisting of aluminum, gallium, iron, boron, titanium,
indium, vanadium and combinations thereof.
14. The method according to claim 13 wherein the trivalent element,
pentavalent element or second tetravalent element is selected from
the group consisting of aluminum, boron, titanium and combinations
thereof.
15. A method according to claim 8 wherein the amine is also small
enough to fit in the pores of the crystalline material.
16. The method according to claim 15 wherein the first tetravalent
element is selected from the group consisting of silicon, germanium
and combinations thereof.
17. The method according to claim 16 wherein the first tetravalent
element is silicon.
18. The method according to claim 15 wherein the trivalent element,
pentavalent element or second tetravalent element is selected from
the group consisting of aluminum, gallium, iron, boron, titanium,
indium, vanadium and combinations thereof.
19. The method according to claim 18 wherein the trivalent element,
pentavalent element or second tetravalent element is selected from
the group consisting of aluminum, boron, titanium and combinations
thereof.
20. The method of claim 15 wherein the crystalline material has,
after calcination, a micropore volume of at least 0.10 cc/g.
21. The method of claim 15 wherein the crystalline material has,
after calcination, a Constraint Index of less than or equal to 2.0.
22. The method of claim 8 15 11 13 14 12 16 18 19 or 17
wherein the amine is 44'-trimethylene dipiperidine.
Molecular sieve description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to crystalline molecular sieve SSZ-47B
having high micropore volume and high catalytic activity, and a
method for preparing such high micropore volume, highly active SSZ-47B
using N-cyclopentyl-14-diazabicyclo[2.2.2]octane cation (referred
to herein as "N-cyclopentyl DABCO cation") structure directing
agent (SDA) in the presence of an amine too large to fit in the
pores of the molecular sieve nonasil, a clathrasil material.
2. State of the Art
Because of their unique sieving characteristics, as well as their
catalytic properties, crystalline molecular sieves and zeolites
are especially useful in applications such as hydrocarbon conversion,
gas drying and separation. Although many different crystalline molecular
sieves have been disclosed, there is a continuing need for new zeolites
with desirable properties for gas separation and drying, hydrocarbon
and chemical conversions, and other applications. New zeolites may
contain novel internal pore architectures, providing enhanced selectivities
in these processes.
SUMMARY OF THE INVENTION
The present invention is directed to a family of crystalline molecular
sieves with unique properties, referred to herein as "molecular
sieve SSZ-47B" or simply "SSZ-47B". Preferably, SSZ-47B
is obtained in its silicate, aluminosilicate, titanosilicate, germanosilicate,
vanadosilicate or borosilicate form. The term "silicate"
refers to a molecular sieve having a high mole ratio of silicon
oxide relative to aluminum oxide (or other metal oxide), preferably
a mole ratio greater than 100 including molecular sieves comprised
entirely of silicon oxide. As used herein, the term "aluminosilicate"
refers to a molecular sieve containing both aluminum oxide and silicon
oxide and the term "borosilicate" refers to a molecular
sieve containing oxides of both boron and silicon.
Molecular sieves, including zeolites, are typically synthesized
by using a structure directing agent ("SDA", sometimes
called a templating agent) in the reaction mixture used to make
the molecular sieve. The SDA is believed to "direct" the
formation of the molecular sieve's crystal structure as the pores
of the molecular sieve form. As such, the SDA must be small enough
to fit within the pores of the desired molecular sieve.
U.S. Pat. No. 6156290 issued Dec. 5 2000 to Lee et al., discloses
zeolite SSZ-47 and a method of making it using a 3(trimethylammonium)-bicyclo[3.2.1]octane
ammonium cation or N,N-dimethyl-3-azoniabicyclo[4.2.1]nonane cation
as an SDA. However, when each of these cations alone is used as
the SDA, significant amounts of nonasil can form as an intergrowth
in the crystal structure of the SSZ-47.
U.S. Pat. No. 5785947 issued Jul. 28 1998 to Zones et al.,
discloses the preparation of zeolites using a small quantity of
an SDA and a larger quantity of an amine component containing at
least one amine having from one to eight carbon atoms, ammonium
hydroxide or mixtures thereof. It is believed that the amines disclosed
in U.S. Pat. No. 5785947 are all small enough to fit in the pores
of nonasil and, therefore, would not prevent the intergrowth of
nonasil during the preparation of SSZ-47B.
It has now been found that SSZ-47B can be synthesized while preventing
the formation of nonasil intergrowth. This is accomplished by including
in the reaction mixture, along with the SDA, a neutral amine that
is too large to fit in the pores of nonasil. Preferably, the amine
is also small enough to fit in the pores of SSZ-47B. In addition
to preventing the formation of nonasil intergrowth, it has been
discovered that the SSZ-47B made in accordance with this invention
has a micropore volume and catalytic activity approximately double
that of the SSZ-47 disclosed in Lee et al.
The diffraction patterns of SSZ-47 and SSZ-47B share similar features
with those of the NON/EUO/NES family of zeolites. The powder diffraction
patterns of SSZ-47 possess a combination of sharp and broad peaks
that are often observed in the powder XRD patterns of disordered
or intergrown materials. The diffraction patterns of SSZ-47 exhibit
a peak at about 9.5.degree. 2.theta. which is very close to the
111 peak of nonasil (NON), a clathrasil material with no accessible
micropore volume. The intensity and position of this peak vary among
different preparations of SSZ-47. However, in contrast with nonasil-type
materials, these samples of SSZ-47 possess micropore volumes of
0.06 0.08. This measured micropore volume is lower than those typically
measured for medium or large pore zeolites. As the relative intensity
of the peak near 9.5.degree. 2.theta. increases, the measured micropore
volume (among different preparations) of the SSZ-47 material decreases.
These data are consistent with an increase in the fraction of nonasil
or other clathrasil-like domains within the zeolite. These data
suggest SSZ-47 may contain clathrasil-like domains intergrown with
EUO- and/or NES-type domains or with domains of other 10-ring and/or
12-ring pore zeolites.
The samples of SSZ-47 are prepared using a combination of a quaternary
ammonium compound and isobutylamine as structure directing agents.
When these samples are calcined in the presence of oxygen, the resulting
materials are often discolored. This result indicates there may
be organic molecules occluded within cage structures that do not
allow access to small molecules such as oxygen. The largest dimensions
of the nonasil cage parallel to the orthorhombic axes of the crystal
structure are 8.9 (y-axis).times.8.4 (x-axis).times.6.5 .ANG. (z-axis).
These dimensions are determined by subtracting the ionic radii of
the oxygen atoms (1.35 .ANG.) from the distances between the centers
of opposing oxygen atoms. Since the dimensions of the quaternary
ammonium compounds are too large to allow their occlusion within
nonasil-type cages, it is likely that the smaller isobutylamine
molecules are occluded within these small cages. This suggests that
amines too large to fit within a nonasil cage may prevent the creation
of these cage structures if they are used in place of isobutylamine
in the zeolite syntheses. Since the nonasil cages are not accessible
to adsorbing molecules, elimination of the nonasil domains might
improve the adsorption or catalytic properties of the material.
It has been found that molecular sieves can be synthesized using
a combination of quaternary ammonium compounds with a large, neutral
amine. Although the diffraction patterns of these materials are
similar to those of SSZ-47 they do not possess the 111 peak of
nonasil and the measured micropore volumes of these materials are
appreciably greater than those of SSZ-47. These improved materials
collectively are referred to herein as "SSZ-47B."
In accordance with the present invention, there is provided a molecular
sieve having a mole ratio greater than about 15 of (1) an oxide
of a first tetravalent element to (2) an oxide of a trivalent element,
pentavalent element, second tetravalent element different from said
first tetravalent element or mixture thereof having, after calcination,
the X-ray diffraction lines of Table II.
The present invention further provides a molecular sieve having
a mole ratio greater than about 15 of (1) an oxide of silicon, germanium
or mixtures thereof to (2) an oxide of aluminum, gallium, iron,
boron, titanium, indium, vanadium or mixtures thereof having, after
calcination, the X-ray diffraction lines of Table II. The present
invention also provides such a molecule sieve having a micropore
volume of at least 0.10. Further provided is such a molecular sieve
having a Constraint Index of less than or equal to 2.0.
For high catalytic activity, the SSZ-47B molecular sieve should
be predominantly in its hydrogen ion form. It is preferred that,
after calcination, at least 80% of the cation sites are occupied
by hydrogen ions and/or rare earth ions. As used herein, "predominantly
in the hydrogen form" means that, after calcination, at least
80% of the cation sites are occupied by hydrogen ions and/or rare
earth ions.
Further provided by the present invention is a molecular sieve
having a composition, as synthesized and in the anhydrous state,
in terms of mole ratios as follows:
TABLE-US-00001 YO.sub.2/W.sub.cO.sub.d >15 M.sub.2/n/YO.sub.2
0.01 0.03 Q/YO.sub.2 0.02 0.05 Amine/YO.sub.2 0.01 0.05
wherein Y is silicon, germanium or a mixture thereof; W is aluminum,
gallium, iron, boron, titanium, indium, vanadium or mixtures thereof;
c is 1 or 2; d is 2 when c is 1 or d is 3 or 5 when c is 2; M is
an alkali metal cation, alkaline earth metal cation or mixtures
thereof; n is the valence of M; and Q is a N-cyclopentyl-14-diazabicyclo[2.2.2]octane
cation, and Amine is an amine too large to fit in the pores of the
molecular sieve nonasil. Preferably, Amine is also small enough
to fit in the pores of the molecular sieve
Further provided by the present invention is a method of preparing
a crystalline material having, after calcination, the X-ray diffraction
lines of Table II comprising (1) an oxide of a first tetravalent
element and (2) an oxide of a trivalent element, pentavalent element,
second tetravalent element which is different from said first tetravalent
element or mixture thereof and having a mole ratio of the first
oxide to the second oxide greater than 15 said method comprising
contacting under crystallization conditions sources of said oxides
and a N-cyclopentyl- 14-diazabicyclo[2.2.2]octane cation and an
amine too large to fit in the pores of the molecular sieve nonasil.
Preferably, the amine is also small enough to fit in the pores of
the crystalline material.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an X-ray diffraction pattern of SSZ-47B after it has
been calcined.
FIG. 2 is an X-ray diffraction pattern of SSZ-47B in the as-made
form, i.e., prior to removal of the SDA from SSZ-47B.
FIG. 3 shows two X-ray diffraction patterns, the top one being
SSZ-47 and the bottom one being SSZ-47B.
DETAILED DESCRIPTION OF THE INVENTION
The present invention comprises a family of crystalline, large
pore molecular sieves designated herein "molecular sieve SSZ-47B"
or simply "SSZ-47B". As used herein, the term "large
pore" means having an average pore size diameter greater than
about 6.0 Angstroms, preferably from about 6.5 Angstroms to about
7.5 Angstroms.
In preparing SSZ-47B, a N-cyclopentyl DABCO cation is used as a
structure directing agent ("SDA"), also known as a crystallization
template. The N-cyclopentyl DABCO cation has the following structure:
##STR00001## N-cyclopentyl DABCO cation can be prepared as described
in U.S. Pat. No. 6033643 issued Mar. 7 2000 to Yuen et al.,
which is incorporated by reference in its entirety.
The SDA cation is associated with an anion (X.sup.-) which may
be any anion that is not detrimental to the formation of the zeolite.
Representative anions include halogen, e.g., fluoride, chloride,
bromide and iodide, hydroxide, acetate, sulfate, tetrafluoroborate,
carboxylate, and the like. Hydroxide is the most preferred anion.
The amine used in combination with the N-cyclopentyl DABCO SDA
is large enough that it will not fit in the pores of the molecular
sieve nonasil. Preferably, it is also small enough that it does
fit in the pores of SSZ-47B. An example of such an amine is 44'-trimethylene
dipiperidine which has the structure
##STR00002##
In general, SSZ-47B is prepared by contacting an active source
of one or more oxides selected from the group consisting of monovalent
element oxides, divalent element oxides, trivalent element oxides,
tetravalent element oxides and/or pentavalent elements with the
SDA and amine.
SSZ-47B is prepared from a reaction mixture having the composition
shown in Table A below.
TABLE-US-00002 TABLE A Reaction Mixture Typical Preferred YO.sub.2/W.sub.aO.sub.b
>15 30 70 OH--/YO.sub.2 0.10 0.50 0.20 0.30 Q/YO.sub.2 0.05 0.50
0.10 0.20 M.sub.2/n/YO.sub.2 0.02 0.40 0.10 0.25 H.sub.2O/YO.sub.2
30 80 35 45 Amine/YO.sub.2 0.05 0.50 0.10 0.20
where Y, W, Q, M, n and Amine are as defined above, and a is 1
or 2 and b is 2 when a is 1 (i.e., W is tetravalent) and b is 3
when a is 2 (i.e., W is trivalent).
In practice, SSZ-47B is prepared by a process comprising: (a) preparing
an aqueous solution containing sources of at least one oxide capable
of forming a crystalline molecular sieve, a N-cyclopentyl DABCO
cation having an anionic counterion which is not detrimental to
the formation of SSZ-47B, and an amine too large to fit in the pores
of the molecular sieve nonasil; (b) maintaining the aqueous solution
under conditions sufficient to form crystals of SSZ-47B; and (c)
recovering the crystals of SSZ-47B.
Accordingly, SSZ-47B may comprise the crystalline material, the
SDA and the amine in combination with metallic and non-metallic
oxides bonded in tetrahedral coordination through shared oxygen
atoms to form a cross-linked three dimensional crystal structure.
The metallic and non-metallic oxides comprise one or a combination
of oxides of a first tetravalent element(s), and one or a combination
of a trivalent element(s), pentavalent element(s), second tetravalent
element(s) different from the first tetravalent element(s) or mixture
thereof. The first tetravalent element(s) is preferably selected
from the group consisting of silicon, germanium and combinations
thereof. More preferably, the first tetravalent element is silicon.
The trivalent element, pentavalent element and second tetravalent
element (which is different from the first tetravalent element)
is preferably selected from the group consisting of aluminum, gallium,
iron, boron, titanium, indium, vanadium and combinations thereof.
More preferably, the second trivalent or tetravalent element is
aluminum or boron.
Typical sources of aluminum oxide for the reaction mixture include
aluminates, alumina, aluminum colloids, aluminum oxide coated on
silica sol, hydrated alumina gels such as Al(OH).sub.3 and aluminum
compounds such as AlCl.sub.3 and Al.sub.2(SO.sub.4).sub.3. Typical
sources of silicon oxide include silicates, silica hydrogel, silicic
acid, fumed silica, colloidal silica, tetra-alkyl orthosilicates,
and silica hydroxides. Boron, as well as gallium, germanium, titanium,
indium, vanadium and iron, can be added in forms corresponding to
their aluminum and silicon counterparts.
A source zeolite reagent may provide a source of aluminum or boron.
In most cases, the source zeolite also provides a source of silica.
The source zeolite in its dealuminated or deboronated form may also
be used as a source of silica, with additional silicon added using,
for example, the conventional sources listed above. Use of a source
zeolite reagent as a source of alumina for the present process is
more completely described in U.S. Pat. No. 5225179 issued Jul.
6 1993 to Nakagawa entitled "Method of Making Molecular Sieves",
the disclosure of which is incorporated herein by reference.
Typically, an alkali metal hydroxide and/or an alkaline earth metal
hydroxide, such as the hydroxide of sodium, potassium, lithium,
cesium, rubidium, calcium, and magnesium, is used in the reaction
mixture; however, this component can be omitted so long as the equivalent
basicity is maintained. The SDA may be used to provide hydroxide
ion. Thus, it may be beneficial to ion exchange, for example, the
halide to hydroxide ion, thereby reducing or eliminating the alkali
metal hydroxide quantity required. The alkali metal cation or alkaline
earth cation may be part of the as-synthesized crystalline oxide
material, in order to balance valence electron charges therein.
The reaction mixture is maintained at an elevated temperature until
the crystals of the SSZ-47B are formed. The hydrothermal crystallization
is usually conducted under autogenous pressure, at a temperature
between 100.degree. C. and 200.degree. C., preferably between 135.degree.
C. and 160.degree. C. The crystallization period is typically greater
than 1 day and preferably from about 3 days to about 20 days.
Preferably, the molecular sieve is prepared using mild stirring
or agitation.
During the hydrothermal crystallization step, the SSZ-47B crystals
can be allowed to nucleate spontaneously from the reaction mixture.
The use of SSZ-47B crystals as seed material can be advantageous
in decreasing the time necessary for complete crystallization to
occur. In addition, seeding can lead to an increased purity of the
product obtained by promoting the nucleation and/or formation of
SSZ-47B over any undesired phases. When used as seeds, SSZ-47B crystals
are added in an amount between 0.1 and 10% of the weight of first
tetravalent element oxide, e.g. silica, used in the reaction mixture.
Once the molecular sieve crystals have formed, the solid product
is separated from the reaction mixture by standard mechanical separation
techniques such as filtration. The crystals are water-washed and
then dried, e.g., at 90.degree. C. to 150.degree. C. for from 8
to 24 hours, to obtain the as-synthesized SSZ-47B crystals. The
drying step can be performed at atmospheric pressure or under vacuum.
SSZ-47B as prepared has a mole ratio of an oxide selected from
silicon oxide, germanium oxide and mixtures thereof to an oxide
selected from aluminum oxide, gallium oxide, iron oxide, boron oxide,
titanium oxide, indium oxide, vanadium oxide and mixtures thereof
greater than about 15 and has, after calcination, the X-ray diffraction
lines of Table II below. SSZ-47B further has a composition, as synthesized
(i.e., prior to removal of the SDA from the SSZ-47B) and in the
anhydrous state, in terms of mole ratios, shown in Table B below.
TABLE-US-00003 TABLE B As-Synthesized SSZ-47B YO.sub.2/W.sub.cO.sub.d
>15 M.sub.2/n/YO.sub.2 0.01 0.03 Q/YO.sub.2 0.02 0.05 Amine/YO.sub.2
0.01 0.05
where Y, W, c, d, M, n, Q and Amine are as defined above.
.sup.13C MASNMR analysis of as-synthesized SSZ-47B provides evidence
that the as-synthesized SSZ-47B contains both the N-cyclopentyl
DABCO SDA and the amine inside the molecular sieve. This is also
evidence that the amine is small enough to fit in the pores of SSZ-47B.
SSZ-47B can be made with a mole ratio of YO.sub.2/W.sub.cO.sub.d
of .infin., i.e., there is essentially no W.sub.cO.sub.d present
in the SSZ-47B. In this case, the SSZ-47B would be an all-silica
material or a germanosilicate. Thus, in a typical case where oxides
of silicon and aluminum are used, SSZ-47B can be made essentially
aluminum free, i.e., having a silica to alumina mole ratio of .infin..
A method of increasing the mole ratio of silica to alumina is by
using standard acid leaching or chelating treatments. Essentially
aluminum-free SSZ-47B can be synthesized using essentially aluminum-free
silicon sources as the main tetrahedral metal oxide component in
the presence of boron. The boron can then be removed, if desired,
by treating the borosilicate SSZ-47B with acetic acid at elevated
temperature (as described in Jones et al., Chem. Mater., 2001 13
1041 1050) to produce an all-silica version of SSZ-47B. SSZ-47B
can also be prepared directly as a borosilicate. If desired, the
boron can be removed as described above and replaced with metal
atoms by techniques known in the art to make, e.g., an aluminosilicate
version of SSZ-47B. SSZ-47B can also be prepared directly as an
aluminosilicate.
Lower silica to alumina ratios may also be obtained by using methods
which insert aluminum into the crystalline framework. For example,
aluminum insertion may occur by thermal treatment of the zeolite
in combination with an alumina binder or dissolved source of alumina.
Such procedures are described in U.S. Pat. No. 4559315 issued
on Dec. 17 1985 to Chang et al.
SSZ-47B, as-synthesized, has a crystalline structure whose X-ray
powder diffraction pattern exhibit the characteristic lines shown
in Table I and is thereby distinguished from other molecular sieves.
TABLE-US-00004 TABLE I As-Synthesized SSZ-47B 2 Theta.sup.(a) d-spacing
(Angstroms) Relative Intensity (%).sup.(b) 7.80 11.3 S 8.54 10.4
W M 19.02 4.67 M 20.36 4.36 VS 22.10 4.02 S VS 23.06 3.86 M 23.74
3.75 M 25.92 3.44 W M 26.46 3.37 W 27.10 3.29 S .sup.(a).+-.0.1
.sup.(b)The X-ray patterns provided are based on a relative intensity
scale in which the strongest line in the X-ray pattern is assigned
a value of 100: W(weak) is less than 20; M(medium) is between 20
and 40; S(strong) is between 40 and 60; VS(very strong) is greater
than 60.
Table IA below shows the X-ray powder diffraction lines for as-synthesized
SSZ-47B including actual relative intensities.
TABLE-US-00005 TABLE IA 2 Theta.sup.(a) d-spacing (Angstroms) Relative
Intensity (%) 7.80 11.3 49 8.54 10.4 19 12.82 6.91 11 15.74 5.63
8 19.02 4.67 30 20.36 4.36 100 22.10 4.02 59 23.06 3.86 22 23.74
3.75 24 25.92 3.44 20 26.46 3.37 18 27.10 3.29 48 28.10 3.18 7 28.76
3.10 9 30.22 2.96 6 32.98 2.72 6 35.42 2.53 7 36.22 2.48 5 36.99
2.43 2 37.34 2.41 5 38.72 2.33 5 39.08 2.30 4 .sup.(a).+-.0.1
After calcination, the SSZ-47B molecular sieves have a crystalline
structure whose X-ray powder diffraction pattern include the characteristic
lines shown in Table II:
TABLE-US-00006 TABLE II Calcined SSZ-47B 2 Theta.sup.(a) d-spacing
(Angstroms) Relative Intensity (%) 7.91 11.18 S 8.68 10.19 M 19.14
4.64 M S 20.51 4.33 VS 22.23 4.00 S 23.27 3.82 M 23.9 3.72 W 26
3.43 W 26.62 3.35 M 27.26 3.27 S .sup.(a).+-.0.1
Table IIA below shows the X-ray powder diffraction lines for calcined
SSZ-47B including actual relative intensities.
TABLE-US-00007 TABLE IIA 2 Theta.sup.(a) d-spacing (Angstroms)
Relative Intensity (%) 7.91 11.18 57.4 8.68 10.19 34.1 9.025 9.80
6.9 11.42 7.75 5.6 12.91 6.86 9.9 14.2 6..24 3.4 15.22 5.82 4.2
15.77 5.62 5.2 19.14 4.64 40.6 20.51 4.33 100.0 22.23 4.00 47.2
23.27 3.82 22.2 23.9 3.72 18.4 26 3.43 10.8 26.62 3.35 25.9 27.26
3.27 60.8 28.26 3.16 4.7 28.97 3.08 6.2 30.33 2.95 8.8 30.95 2.89
0.8 33.18 2.70 4.2 34.63 2.59 6.4 35.56 2.52 8.3 36.51 2.46 3.4
37.42 2.40 8.8 .sup.(a).+-.0.1
The X-ray powder diffraction patterns were determined by standard
techniques. The radiation was the K-alpha/doublet of copper. The
peak heights and the positions, as a function of 2.theta. where
.theta. is the Bragg angle, were read from the relative intensities
of the peaks, and d, the interplanar spacing in Angstroms corresponding
to the recorded lines, can be calculated.
The variation in the scattering angle (two theta) measurements,
due to instrument error and to differences between individual samples,
is estimated at .+-.0.1 degrees.
The X-ray diffraction pattern of Table I is representative of "as-synthesized"
or "as-made" SSZ-47B molecular sieves. Minor variations
in the diffraction pattern can result from variations in the silica-to-alumina
or silica-to-boron mole ratio of the particular sample due to changes
in lattice constants. In addition, sufficiently small crystals will
affect the shape and intensity of peaks, leading to significant
peak broadening.
Representative peaks from the X-ray diffraction pattern of calcined
SSZ-47B are shown in Table II. Calcination can also result in changes
in the intensities of the peaks as compared to patterns of the "as-made"
material, as well as minor shifts in the diffraction pattern. The
molecular sieve produced by exchanging the metal or other cations
present in the molecular sieve with various other cations (such
as H.sup.+ or NH.sub.4.sup.+) yields essentially the same diffraction
pattern, although again, there may be minor shifts in the interplanar
spacing and variations in the relative intensities of the peaks.
Notwithstanding these minor perturbations, the basic crystal lattice
remains unchanged by these treatments.
Crystalline SSZ-47B can be used as-synthesized, but preferably
will be thermally treated (calcined). Usually, it is desirable to
remove the alkali metal cation by ion exchange and replace it with
hydrogen, ammonium, or any desired metal ion. The molecular sieve
can be leached with chelating agents, e.g., EDTA or dilute acid
solutions, to increase the silica to alumina mole ratio. The molecular
sieve can also be steamed; steaming helps stabilize the crystalline
lattice to attack from acids.
The molecular sieve can be used in intimate combination with hydrogenating
components, such as tungsten, vanadium, molybdenum, rhenium, nickel,
cobalt, chromium, manganese, or a noble metal, such as palladium
or platinum, for those applications in which a hydrogenation-dehydrogenation
function is desired.
Metals may also be introduced into the molecular sieve by replacing
some of the cations in the molecular sieve with metal cations via
standard ion exchange techniques (see, for example, U.S. Pat. No.
3140249 issued Jul. 7 1964 to Plank et al.; U.S. Pat. No. 3140251
issued Jul. 7 1964 to Plank et al.; and U.S. Pat. No. 3140253
issued Jul. 7 1964 to Plank et al.). Typical replacing cations
can include metal cations, e.g., rare earth, Group IA, Group IIA
and Group VIII metals, as well as their mixtures. Of the replacing
metallic cations, cations of metals such as rare earth, Mn, Ca,
Mg, Zn, Cd, Pt, Pd, Ni, Co, Ti, Al, Sn, and Fe are particularly
preferred.
The hydrogen, ammonium, and metal components can be ion-exchanged
into the SSZ-47B. The SSZ-47B can also be impregnated with the metals,
or the metals can be physically and intimately admixed with the
SSZ-47B using standard methods known to the art.
Typical ion-exchange techniques involve contacting the synthetic
molecular sieve with a solution containing a salt of the desired
replacing cation or cations. Although a wide variety of salts can
be employed, chlorides and other halides, acetates, nitrates, and
sulfates are particularly preferred. The molecular sieve is usually
calcined prior to the ion-exchange procedure to remove the organic
matter present in the channels and on the surface, since this results
in a more effective ion exchange. Representative ion exchange techniques
are disclosed in a wide variety of patents including U.S. Pat. No.
3140249 issued on Jul. 7 1964 to Plank et al.; U.S. Pat. No.
3140251 issued on Jul. 7 1964 to Plank et al.; and U.S. Pat.
No. 3140253 issued on Jul. 7 1964 to Plank et al.
Following contact with the salt solution of the desired replacing
cation, the molecular sieve is typically washed with water and dried
at temperatures ranging from 65.degree. C. to about 200.degree.
C. After washing, the molecular sieve can be calcined in air or
inert gas at temperatures ranging from about 200.degree. C. to about
800.degree. C. for periods of time ranging from 1 to 48 hours, or
more, to produce a catalytically active product especially useful
in hydrocarbon conversion processes.
Regardless of the cations present in the synthesized form of SSZ-47B,
the spatial arrangement of the atoms which form the basic crystal
lattice of the molecular sieve remains essentially unchanged.
SSZ-47B can be formed into a wide variety of physical shapes. Generally
speaking, the molecular sieve can be in the form of a powder, a
granule, or a molded product, such as extrudate having a particle
size sufficient to pass through a 2-mesh (Tyler) screen and be retained
on a 400-mesh (Tyler) screen. In cases where the catalyst is molded,
such as by extrusion with an organic binder, the SSZ-47B can be
extruded before drying, or, dried or partially dried and then extruded.
SSZ-47B can be composited with other materials resistant to the
temperatures and other conditions employed in organic conversion
processes. Such matrix materials include active and inactive materials
and synthetic or naturally occurring zeolites as well as inorganic
materials such as clays, silica and metal oxides. Examples of such
materials and the manner in which they can be used are disclosed
in U.S. Pat. No. 4910006 issued May 20 1990 to Zones et al.,
and U.S. Pat. No. 5316753 issued May 31 1994 to Nakagawa, both
of which are incorporated by reference herein in their entirety.
SSZ-47B is useful in catalysts for a variety of hydrocarbon conversion
reactions such as hydrocracking, dewaxing, isomerization and the
like.
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