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 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.
2. 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.
3. A molecular sieve according to claim 1 or 2 wherein the oxides
comprise silicon oxide and aluminum oxide.
4. A molecular sieve according to claim 1 or 2 wherein the oxides
comprise silicon oxide and boron oxide.
5. A molecular sieve according to claim 1 or 2 wherein the oxide
comprises silicon oxide.
6. A molecular sieve according to claim 1 or 2 wherein said molecular
sieve is predominantly in the hydrogen form.
7. A molecular sieve according to claim 1 or 2 wherein said molecular
sieve is substantially free of acidity.
8. A molecular sieve according to claim 1 or 2 wherein said molecular
sieve has a micropore volume of at least 0.10 cc/g.
9. A molecular sieve according to claim 1 or 2 wherein said molecular
sieve has a Constraint Index of less than or equal to 2.0.
10. A molecular sieve having a composition, as synthesized and
in the anhydrous state, in terms of mole ratios as follows:
9 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 the
molecular sieve nonasil.
11. A molecular sieve according to claim 10 wherein the amine is
also small enough to fit in the pores of the molecular sieve.
12. A molecular sieve according to claim 10 wherein W is aluminum
and Y is silicon.
13. A molecular sieve according to claim 10 wherein W is boron
and Y is silicon.
14. A molecular sieve according to claim 12 wherein the amine is
also small enough to fit in the pores of the molecular sieve.
15. A molecular sieve according to claim 13 wherein the amine is
also small enough to fit in the pores of the molecular sieve.
16. A molecular sieve according to claim 10 11 12 13 14 or
15 wherein the amine is 44'-trimethylene dipiperidine.
17. 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.
18. A method according to claim 17 wherein the amine is also small
enough to fit in the pores of the molecular sieve.
19. The method according to claim 17 wherein the first tetravalent
element is selected from the group consisting of silicon, germanium
and combinations thereof.
20. The method according to claim 17 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.
21. The method according to claim 20 wherein the trivalent element,
pentavalent element or second tetravalent element is selected from
the group consisting of aluminum, boron, titanium and combinations
thereof.
22. The method according to claim 19 wherein the first tetravalent
element is silicon.
23. The method of claim 17 wherein the crystalline material has,
after calcination, a micropore volume of at least 0.10 cc/g.
24. The method of claim 17 wherein the crystalline material has,
after calcination, a Constraint Index of less than or equal to 2.0.
25. The method according to claim 18 wherein the first tetravalent
element is selected from the group consisting of silicon, germanium
and combinations thereof.
26. The method according to claim 18 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.
27. The method according to claim 26 wherein the trivalent element,
pentavalent element or second tetravalent element is selected from
the group consisting of aluminum, boron, titanium and combinations
thereof.
28. The method according to claim 25 wherein the first tetravalent
element is silicon.
29. The method of claim 18 wherein the crystalline material has,
after calcination, a micropore volume of at least 0.10 cc/g.
30. The method of claim 18 wherein the crystalline material has,
after calcination, a Constraint Index of less than or equal to 2.0.
31. The method of claim 17 18 19 20 21 22 25 26 27 or
28 wherein the amine is 44'-trimethylene dipiperidine.
Molecular sieve description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] 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.
[0003] 2. State of the Art
[0004] 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
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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.
[0009] 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.
[0010] 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.
[0011] 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.
[0012] 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."
[0013] 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.
[0014] 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.
[0015] 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.
[0016] 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:
1 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
[0017] 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]oc-
tane 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
[0018] 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
[0019] FIG. 1 is an X-ray diffraction pattern of SSZ-47B after
it has been calcined.
[0020] 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.
[0021] 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
[0022] 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.
[0023] 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: 1
[0024] 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.
[0025] 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.
[0026] 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 2
[0027] 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.
[0028] SSZ-47B is prepared from a reaction mixture having the composition
shown in Table A below.
2TABLE 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
[0029] 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).
[0030] In practice, SSZ-47B is prepared by a process comprising:
[0031] (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;
[0032] (b) maintaining the aqueous solution under conditions sufficient
to form crystals of SSZ-47B; and
[0033] (c) recovering the crystals of SSZ-47B.
[0034] 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.
[0035] 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.
[0036] 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.
[0037] 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.
[0038] 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.
[0039] Preferably, the molecular sieve is prepared using mild stirring
or agitation.
[0040] 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.
[0041] 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.
[0042] 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.
3TABLE 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
[0043] where Y, W, c, d, M, n, Q and Amine are as defined above.
[0044] .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.
[0045] 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.
[0046] 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.
[0047] 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.
4TABLE 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.
[0048] Table IA below shows the X-ray powder diffraction lines
for as-synthesized SSZ-47B including actual relative intensities.
5TABLE 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
[0049] 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:
6TABLE 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
[0050] Table IIA below shows the X-ray powder diffraction lines
for calcined SSZ-47B including actual relative intensities.
7TABLE 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
[0051] 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.
[0052] 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.
[0053] 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.
[0054] 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.
[0055] 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.
[0056] 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.
[0057] 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.
[0058] 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.
[0059] 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.
[0060] 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.
[0061] 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.
[0062] 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.
[0063] 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.
[0064] SSZ-47B is useful in catalysts for a variety of hydrocarbon
conversion reactions such as hydrocracking, dewaxing, isomerization
and the like.
EXAMPLES
[0065] The following examples demonstrate but do not limit the
present invention.
Example 1
[0066] A reaction mixture is prepared in the Teflon cup of a Parr
23 ml reactor by combining the following: 2 millimoles (0.42 gram)
of 44'-trimethylene dipiperidine, 1.0 millimole of N-cyclopentyl
DABCO hydroxide in a total of 9.25 grams of water, 0.088 gram of
Reheis F-2000 alumina (53-56 wt. % Al.sub.2O.sub.3), 3 grams of
1 N KOH and 0.90 gram of Cabosil M-5 fumed silica. The first two
components represent the amine that is too large to form nonasil
and the SDA that forms SSZ-47B, respectively. The reaction mixture
is heated at 170.degree. C. while being tumbled at 43 RPM. The reaction
mixture has a silica/alumina mole ratio (SAR) of 32. The SSZ-47B
product (identified by X-ray diffraction) forms after nine days.
Example 2
[0067] The reaction of Example 1 is repeated, except the alumina
content is reduced to 0.066 gram. The SAR of the reaction mixture
is 40. The reaction produces SSZ-47B (identified by X-ray diffraction).
Example 3
[0068] The reaction of Example 1 is repeated, except the alumina
content is reduced to 0.044 gram. The SAR of the reaction mixture
is 64. The reaction produces SSZ-47B with a little quartz impurity
(identified by X-ray diffraction).
Example 4
[0069] The reaction of Example 1 is repeated, except the N-cyclopentyl
DABCO hydroxide content is reduced to 0.5 millimole. The reaction
produces SSZ-47B (identified by X-ray diffraction).
Example 5
[0070] The reaction of Example 4 is repeated, except that the reaction
mixture is seeded with 2 wt. % (based on the weight of silica) SSZ-47B
crystals from the product of Example 1. The reaction produces SSZ-47B
(identified by X-ray diffraction).
Example 6
Calcination of SSZ-47B
[0071] SSZ-47B as synthesized in Example 3 is calcined to remove
the structure directing agent (SDA) and amine. A thin bed of SSZ-47B
in a calcination dish is heated in a muffle furnace from room temperature
to 120.degree. C. at a rate of 1.degree. C./minute and held for
2 hours. Then, the temperature is ramped up to 540.degree. C. at
a rate of 1.degree. C./minute and held for 5 hours. The temperature
is ramped up again at 1.degree. C./minute to 595.degree. C. and
held there for 5 hours. A 50/50 mixture of air and nitrogen passes
through the muffle furnace at a rate of 20 standard cubic feet (0.57
standard cubic meters) per minute during the calcination process.
Example 7
Ammonium-Ion Exchange of SSZ-47B
[0072] The Na.sup.+ form of SSZ-47B (prepared as in Example 3 or
as in Example 5 and calcined as in Example 6) is converted to NH.sub.4.sup.+-SSZ-47B
form by heating the material in an aqueous solution of NH.sub.4NO.sub.3
(typically 1 gm NH.sub.4NO.sub.3/1 gm SSZ-47B in 20 ml H.sub.2O)
at 90.degree. C. for 2-3 hours. The mixture is then filtered and
the obtained NH.sub.4-exchanged-product is washed with de-ionized
water and dried. The ion exchange procedure is repeated again. The
NH.sub.4.sup.+ form of SSZ-47B can be converted to the H.sup.+ form
by calcination (as described in Example 6) to 540.degree. C.
Example 8
Nitrogen Adsorption Analysis
[0073] The hydrogen form of the products of Example 3 (after a
treatment as in Examples 6 and 7 is subjected to a micropore volume
analysis using nitrogen as adsorbate and via the BET method. The
micropore volume is 0.153 cc/g, thus exhibiting considerable void
volume.
Example 9
Constraint Index
[0074] The hydrogen form of SSZ-47B of Example 3 (after treatment
according to Examples 6 and 7) is pelletized at 3 KPSI, crushed
and granulated to 20-40 mesh. A 0.6 gram sample of the granulated
material is calcined in air at 540.degree. C. for 4 hours and cooled
in a desiccator to ensure dryness. Then, 0.5 gram is packed into
a 3/8 inch stainless steel tube with alundum on both sides of the
molecular sieve bed. A Lindburg furnace is used to heat the reactor
tube. Helium is introduced into the reactor tube at 10 cc/min. and
at atmospheric pressure. The reactor is heated to about 315.degree.
C., and a 50/50 feed of n-hexane and 3-methylpentane is introduced
into the reactor at a rate of 8 .mu.l/min. The feed is delivered
by a Brownlee pump. Direct sampling into a GC begins after 10 minutes
of feed introduction. The Constraint Index (CI) value is calculated
from the GC data using methods known in the art. SSZ-47B has a CI
of 1.5 and a conversion at 600.degree. F (315.degree. C.) of 80.6%
after 20 minutes on stream. The data suggests a large pore molecular
sieve. |