GB2226307A - "Crystalline, porous borosilicate isostructural with levynite" - Google Patents
"Crystalline, porous borosilicate isostructural with levynite" Download PDFInfo
- Publication number
- GB2226307A GB2226307A GB8927013A GB8927013A GB2226307A GB 2226307 A GB2226307 A GB 2226307A GB 8927013 A GB8927013 A GB 8927013A GB 8927013 A GB8927013 A GB 8927013A GB 2226307 A GB2226307 A GB 2226307A
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- GB
- United Kingdom
- Prior art keywords
- crystalline
- levynite
- boron
- calcined
- isostructural
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B35/00—Boron; Compounds thereof
- C01B35/08—Compounds containing boron and nitrogen, phosphorus, oxygen, sulfur, selenium or tellurium
- C01B35/10—Compounds containing boron and oxygen
- C01B35/1009—Compounds containing boron and oxygen having molecular-sieve properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/86—Borosilicates; Aluminoborosilicates
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Silicates, Zeolites, And Molecular Sieves (AREA)
Abstract
The borosilicate in its calcined and anhydrous state has the formula: M2/nO, (1-x) B2O3, x M'2O3, y SiO2 wherein: M is metal cation with a valency of n, or H<+>; M' is Al, Fe, Ga, Cr, V or Mn; x is 0 to 0,3; and y is 5 to 40. Silicon can be partially substituted by Ge, Ti or Zr.
Description
"CRYSTALLINE, POROUS BOROSILICATE ISOSTRUCTURAL WITH
LEVYNITE"
The present invention relates to the syntesis of a novel crystalline, porous borosilicate isostructural with a natural zeolite known as levynite.
In nature, a Large number of borosilicates exist, in most of which boron has a trigonal, planar coordination with oxygen. Borosilicates in which boron is in tetrahedral coordination with oxygen (such as, e.g., reedmergnerite mineral, NaBSiJOs, described by Appleman and Clark, Amer. Mineral. (1965), 5, 1327 are Less numerous, and, anyway, no examples of crystalline, porous borosilicates with zeolitic structure are known. This is indicative of the greater difficulty to assume tetrahedral coordination boron has, as compared to aluminum.
However, the preparations have been described recently of some crystalline, porous borosilicates isostructural with well-known synthetic zeolites. These materials were given the name of "boralites" by some
Authors EM. Taramasso, G. Perego, B. Notari, Proc. 5th
Int.Conf.on Zeolites, Naples, L.W. Rees Ed., Heyden, London (1980), 407. Boralites denominated AMS-1B and USI-lOB, isostructural with ZSM-5 have been respectively claimed in Dutch patent application No. 77-11239 and in United
Kingdom patent No. 2,062,603.
In United Kingdom patent N.2024790
the processes are disclosed for the preparations of four boralites, respectively named BOR-A, BOR-B, BOR- C and BOR-D, respectively isostructural with zeolites NU-1, Beta, ZSM-5 and ZSM-11.
In United Kingdom patent No. 2,120,226 the synthesis is claimed of a family of boralites, denominated BOR-E, having an intermediate structure between BOR-C and BOR-D.
The possibility has been claimed recently of synthetizing crystalline, porous borosilicates isostructural with zeolites of natural origin, such as in
European patent application No. 234,755 relevant to the synthesis of a boralite isostructural with ferrierite, and in German patent application No. 3,537,998 relevant to the synthesis of a borosilicate isostructiral with sodalite.
The present Applicant has found now that a crystalline, porous borosilicate isostructural with levynite, a well-known natural zeolite, can be synthet i zed.
Levynite was also obtained by means of a hydrothermal synthesis, using the following as template agents: - 1-methyl-1-azonium-4-azobicyclo-2,2,2-octane ion (a
material denominated ZK-20, U.S. patent No. 3,459,676); - ions derived from quinuclidine (a material denominated
NU-3. EP patent No. 40,016); - N-methyl-quinuclidinium ions (a material denominated LZ
132, EP 91,048); - 2-(hydroxyalkyl)-trialkyl-ammonium salts (a material
denominated ZSM-45, EP 107,370).
All of the hereinabove reported patents relate to the synthesis of crystaLline, porous alumino-silicates.
In European patent application No. !"5,031 the possi hi Ii ty of obtaining a crystalline, porous ferrosilicata isostructural with levynite is furthermore claimed.
To date, the possibility of the isomorphous substitution of aluminum by boron was not known for this zeolitic structure.
The phase isostructural with levynite, to which reference is made in the following by the term '1boron- levynite", is characterized by a framework constituted by boron, silicon and oxygen and, owing to the smaLler covalent radius of boron than of aluminum, the volume of the elementary cell is significantly smalter than of levynite. The two materials are therefore different from each other in composition, in the reduced sizes of the elementary crystalline cell and hence of the pores, and in the strength of the acidic sites. In fact, it is known that boron generates much weaker acidic sites than as generated by aluminum tC. Chu, G.H. Kuehl, R.M. Lago, C.D.Chang, J. of Catal. 23, 451 (1985)] and such a property generates several applications, as disclosed in
United Kingdom patent N. 2025454 and in European patent applications No. 184,307; No. 180,308; and No.
186,395.
Boron-levynite can be also synthetized in presence of other trivalent metal cations capable of partially replacing boron in the crystal lattice, with B-metallevynites being consequently obtained.
The crystalline, porous borosilicate isostructurat with levynite according to the present invention, denominated by the present Applicant as "boron-levynite'r has, in its calcined and anhydrous state, the following empirical formula: M2 /neo, Cl - x ) 82 03 / x M ' 2 03 o y Si 02 (I Y wherein:
M is either a metal cation with a valency of n, or H+;
M' is a metal which can be selected from the group
consisting of Al, Fe, Ga, Cr, V or Mn, either alone or
in mixture with one another; x is a numeral comprised within the range of from 0 to
0.3; and y is a numeral comprised within the range of from 5 to
40, wherein silicon can be partially substituted by Ge, Ti or
Zr.
The X-ray diffraction spectrum of calcined boronlevynite in its acidic form is characterized by the hereinunder reported interplanar distances and intensities of the main reflections:
Table 1
Boron-Levynite calcined at 550 C, H+ form daa I/Io
9.94 + 0.10 10 - 20
7.87 + 0.10 100
7.44 + 0.10 5 - 15
6.40 + 0.10 75 - 85
4.97 + 0.07 20 - 30
4.14 + 0.07 20 - 30
3.93 + 0.07 40 - 50
3.70 + 0.05 10 - 20
3.20 i 0.03 5 - 15
3.06 ' 0.03 10 - 20
2.69 + 0.02 10 - vr The diffraction spectrum of boron-levynite can be interpreted on the basis of the same elementary cell typical of natural levynite, with - a = 12.90 + 0.05 , and - c = 22.25 + 0.05 , and a consequent volume of the elementary cell of 3206 + 35 A3.
The corresponding volume as measured on a synthetic levynite having a molar ratio of SiO2/Al203 = 45 is of 3370 t 5 A3 (value computed from the RX spectrum reported for zeolite Nu-3 in the acidic form in EP patent No.
40,016), and the one reported for natural levynite (SiO2/Al203 = 4) is of 3546 + 30 R3 (S. Merlino, E.
Galli, A. Albert, Tschermaks Min. Petr. Mitt., 1975, 22, 117-129). Boron-levynite can be advantageously used for its properties of ionic exchange, as a molecular sieve and as a catalyst.
The different sizes of the channels relatively to levynite endow the herein disclosed crystalline borosilicate with novel characteristics as a molecular sieve.
Boron-levynite can be obtained by hydrothermal synthesis in an autoclave under the autogenous pressure of the reaction mass and at a temperature comprised within the range of from 150 to 2200C and within a reaction time of less than 10 days, by starting from a silica source, such as silica gel, colloidal silica, and so forth, a boron source, such ad H3B03 , its alkali-metal and ammonium salts, trialkylborates, and so forth, a cyclic amine, such as quinuclidine as the template asen; and, optionaLly, alcaline hydroxides.
The crystalline, porous material å;scharged from th - autoclave is collected by filtration, is washed on the filter with demineralized water and is then dried in an oven at 1200C for some hours.
The so-obtained product complies in its dried form with the following general formula, with its components being expressed as oxides:
p M2/nO, q R, (1-x)B203, x M1203, y Six2, z H20 (2) wherein: M- is either a metal cation with a valency of n, or H+.
or NH4+; (2)
R is quinuclidine,
M' is a metal selected from the group consisting of Al,
Fe, Ga, Cr, V or Mn, either alone, or in mixture with
each other; p is a numeral comprised within the range of from 0 to
0.2; q is a numeral comprised within the range of from 1.5 to
5.0; x is a numeral comprised within the range of from 0 to
0.3; y is a numeral comprised within the range of from 5 to
40, and z is a numeral comprised within the range of from 1 to
20, with silicon being possibly partially substituted by Ge,
Ti or Zr.
The X-ray powder diffraction spectrum of boronlevynite in its desiccated form, recorded by means of a
Philips goniometer equipped with an electronic system for impulse countinc, using Cu K > radiation, is characterizea the hereinunder reported interplanar distances and intensities of the main reflections::
Table 2
Boron-Levynite dried at 120 C
d, I/Io
9.99 + 0.15 10 - 20
7.84 + 0.10 40 - 50
7.31 + 0.10 2 - 10
6.47 + 0.10 20 - 30
5.43 + 0.10 5 - 15
4.99 + 0.07 70 - 85
4.93 + 0.07 10 - 20
4.85 + 0.07 10 - 20
4.16 + 0.07 5 - 15
4.08 + 0.05 50 - 65
3.95 + 0.05 100
3.74 + 0.05 10 - 25
3.65 + 0.05 5 - 15
3.24 + 0.03 15 - 25
3.05 + 0.03 20 - 30
3.02 + 0.03 20 - 30
2.99 + 0.03 5 - 10
2.72 t 0.02 35 - 50
2.52 + 0.02 5 - 15
The I.R. sprectrum of boron-levynite in the region from 1600 to 400 cm-1 is reported in Figure 1. The desiccated sample can be calcined and exchanged according to the processes known from the prior art in order to yield other cationic forms.
After calcination at 550 C in air for 5 hours, the exchanged sample in ammonium form is in its acidic form.
In order to better illustrate the meaning of the instant invention, some examples of preparation are reported in the following. However, in no way such examples should be regarded as being limitative of the same invention.
Example 1
15 g of quinuclidine, previousLy dissolved in 10 g of demineralized water, is added to 39 g of Ludox HS at 40%.
- The so obtained solution is kept with stirring for about 30 minutes.
In the mean time, a second solution is prepared by adding, in the order: 61 g of demineralized water, 15 g of quinuclidine and 11 g of boric acid.
The second solution is added to the first one, and the whole mixture is kept stirred for about 1 hour.
A clear solution with a pH value of 11.3 is obtained. This solution is charged to an autoclave, fastened onto a swinging support basket inside an oven, and is kept 6 days at 1700 C, with the pressure inside the autoclave being autogenous pressure.
The sample is then cooled down to room temperature, and the crystalline product is recovered by filtration, is washed and dried at 1200C for 2 hours.
The X-ray diffraction spectrum of the sample obtained after drying and after the exchange into the acidic form shows the reflections reported in Tab I-es 1 and 2, and is hence identified as a boron-levynite.
The chemical analysis of the dried sample, expressed as weight % values, is as follows: C=12.7; N=2.4s; Si02=72.3%; Na20=50 ppm; B2O3 =@.9%.
Example 2
14 g of quinuclidine, previously dissolved in 10 g of demineralized water, is added to 39 9 of Ludox HS at 40%.
The so obtained solution is kept with stirring for about 30 minutes.
In the mean time, a second solution is prepared by adding, in the order: 60 g of demineralized water, 2 g of sodium hydroxide and 11 g of boric acid.
The second solution is added to the first one, and the whole mixture is kept stirred for about 1 hour.
An opalescent suspension with a pH value of 11.2 is obtained. This solution is charged to an autoclave, fastened onto a swinging support basket inside an oven, and is kept 6 days at 1700 C, with the pressure inside the autoclave being autogenous pressures
The sample is then cooled down to room temperature, and the crystalline product is recovered by filtration, is washed and dried at 1200C for 2 hours.
The chemical analysis of the dried sample, expressed as weight X values, is as follows:
C=17.0%; N=3.0%; Na20=0.10%; Si02=68.8%; B2O3=3.8%.
The X-ray diffraction spectrum of the dried sample is the same as reported in Table 2.
Example~3
15 g of quinuclidine, previously dissolved in 10 g of demineralized water, is added to 39 g of Ludox HS at 40%.
The so obt3ined solution i s kept w t h shirring for about 30 minutes.
In the mean time, a second solution is prepared by adding, in the order: 60 g of demineralized water, 2 g of sodium hydroxide, 0.2 g of sodium aluminate and 11 g of boric acid.
This second solution is added to the first one, and the whole mixture is kept stirred for about 1 hour.
An opalescent suspension with a pH value of 11.3 is obtained. This solution is charged to an autoclave, fastened onto a swinging support basket inside an oven, and is kept 6 days at 1700C, with the pressure inside the autoclave being the autogenous pressure.
The sample is then recovered by filtration, washing and drying at 1200C for 2 hours.
The chemical analysis of the dried sample, expressed as weight % values, is as follows: C=14.7%; N=2.4'; Na20=0.3%; SiO2=65.12; B203=3.8%;
A 1203=0.6% The X-ray diffraction spectrum of the dried sample is the same as reported in Table 2.
Example 4
15 g of quinuclidine, previously dissolved in 10 g of demineralized water, is added to 39 9 of Ludox HS at 40%.
The so obtained solution is kept with stirring for about 30 minutes.
In the mean time, a second solution is prepared by adding, in the order: 60 g of demineralized water, 2 g of sodium hydroxide, 0.9 g of iron nitrate hydrate and 11 g of boric acid.
This second solution is added to the first one, and the whole mixture is kept stirred for about 1 hour.
An opalescent suspension with a pH value of 11.0 is obtained. This solution is charged to an autoclave, fastened onto a swinging support basket inside an oven, and is kept 6 days at 1700C, with the pressure inside the autoclave being the autogenous pressure.
The sample is then recovered by filtration, washing ad drying at 1200C for 2 hours.
The chemical analysis of the dried sample, expressed as weight % values, is as follows: C=15.1X.; N=2.5%; Na2O=0.2%; SiO2=70.1%; B203=4.O%; Fe 03=0.7% The X-ray diffraction spectrum of the dried sample is the same as reported in Table 2.
Claims (1)
1. Crystalline porous borosilicate, isostructural with levynite containing silicon and boron oxides, having in its calcined and anhydrous state the following empirical formula: M2/nO. (1-x)B2030xM'2030ySi02 (I) wherein M is either a metal cation with a valency of n br H+, M' is one or more metals selected from Al, Fe,
Ga, Cr, V and Mn, x is from 0 to 0.3, and y is from 5 to 40; and wherein the silicon can be partially replaced by Ge, Ti and/or Zr; and having in its calcined state and in its acidic form an X-ray diffraction spectrum in which the most significant lines are: d i I/Io
9.94 + 0.10 10 - 20
7.87 + 0.10 100
7.44 + 0.10 5 - 15
6.40 + 0.10 75 - 85
4.97 + 0.07 20 - 30
4.14 + 0.07 20 - 30
3.93 + 0.07 40 - 50
3.70 + 0.05 10 - 20
3.20 + 0.03 5 - 15
3.06 + 0.03 10 - 20
2.69 + 0.02 10 - 20 wherein d are the interplanar distances expressed as and I/Io are the relative intensities.
2. A process for preparing borosilicate as claimed in claim 1, which comprises subjecting a reaction mixture comprising a silica source, a boron source, a cyclic amine and, optionally, an alkali metal or alkaline earth metal hydroxide, to hydrothermal synthesis in an autoclave under autogenous pressure and at a temperature of from 150 to 2200C and for a time of less than 10 days, the resulting crystalline material being dried and calcined.
3. A process according to claim 2, wherein the silica source is silica gel or colloidal silica.
4. A process according to claim 2 or 3, wherein boron source is H3BO3, a trialkylborate, or an alkali metal or ammonium salt thereof.
5. A process according to claim 2, 3 or 4, wherein the cyclic amine is quinuclidine.
6. A process according to claim 2, substantially as described in any of the foregoing Examples.
Process for preparing the crystalline, porous borositicate isostructural with levynite according to cLaim 1, characterized in that said process is carried out by hydrothermal synthesis in an autoclave under the autogenous pressure of the reaction mixture and at a temperature comprised within the range of from 150 to 2200C and within a reaction time of less than 10 days, by starting from a silica source, a boron source, a cyclic amine as the template agent and, optionally, alcaline hydroxides, with a crystalline, porous material being obtained which is collected by filtration, is washed on the filter with demineralized water and is dried in an oven at a temperature of about 1200C for some hours, and is then calcined at a temperature of round 5500C in air, for about 5 hours.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT8822899A IT1227887B (en) | 1988-12-09 | 1988-12-09 | ISOSTRUCTURAL POROUS CRYSTALLINE BOROSILICATE WITH LEVYNITE |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8927013D0 GB8927013D0 (en) | 1990-01-17 |
| GB2226307A true GB2226307A (en) | 1990-06-27 |
| GB2226307B GB2226307B (en) | 1992-06-10 |
Family
ID=11201683
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8927013A Expired - Lifetime GB2226307B (en) | 1988-12-09 | 1989-11-29 | Crystalline,porous borosilicate isostructural with levynite |
Country Status (3)
| Country | Link |
|---|---|
| FR (1) | FR2640256B1 (en) |
| GB (1) | GB2226307B (en) |
| IT (1) | IT1227887B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106395850A (en) * | 2015-07-29 | 2017-02-15 | 住友化学株式会社 | A manufacturing method of zeolite, and a manufacturing method of epsilon-caprolactam |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1587921A (en) * | 1976-10-18 | 1981-04-15 | Standard Oil Co | Crystalline borosilicate and process for using same |
| GB2062603A (en) * | 1979-11-07 | 1981-05-28 | Nat Distillers Chem Corp | Crystalline borosilicate compositions |
| EP0131390A2 (en) * | 1983-07-06 | 1985-01-16 | Imperial Chemical Industries Plc | Zeolites |
| EP0234755A2 (en) * | 1986-01-31 | 1987-09-02 | Amoco Corporation | Borosilicate molecular sieve |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4285919A (en) * | 1978-12-26 | 1981-08-25 | Standard Oil Company (Indiana) | Method of preparing a metal-cation-deficient crystalline borosilicate |
| DE3165950D1 (en) * | 1980-05-13 | 1984-10-18 | Ici Plc | ZEOLITE NU-3 |
| EP0054364B1 (en) * | 1980-12-11 | 1985-04-24 | Imperial Chemical Industries Plc | Zeolites |
| US4514516A (en) * | 1981-08-28 | 1985-04-30 | Standard Oil Company (Indiana) | Method for manufacture of AMS-1B crystalline borosilicate molecular sieve with low sodium content |
| EP0115031A1 (en) * | 1982-12-23 | 1984-08-08 | Union Carbide Corporation | Ferrosilicate molecular sieve composition |
-
1988
- 1988-12-09 IT IT8822899A patent/IT1227887B/en active
-
1989
- 1989-11-29 GB GB8927013A patent/GB2226307B/en not_active Expired - Lifetime
- 1989-12-07 FR FR8916205A patent/FR2640256B1/en not_active Expired - Lifetime
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1587921A (en) * | 1976-10-18 | 1981-04-15 | Standard Oil Co | Crystalline borosilicate and process for using same |
| GB2062603A (en) * | 1979-11-07 | 1981-05-28 | Nat Distillers Chem Corp | Crystalline borosilicate compositions |
| EP0131390A2 (en) * | 1983-07-06 | 1985-01-16 | Imperial Chemical Industries Plc | Zeolites |
| EP0234755A2 (en) * | 1986-01-31 | 1987-09-02 | Amoco Corporation | Borosilicate molecular sieve |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106395850A (en) * | 2015-07-29 | 2017-02-15 | 住友化学株式会社 | A manufacturing method of zeolite, and a manufacturing method of epsilon-caprolactam |
| CN106395850B (en) * | 2015-07-29 | 2021-05-25 | 住友化学株式会社 | Method for producing zeolite and method for producing epsilon-caprolactam |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2226307B (en) | 1992-06-10 |
| FR2640256B1 (en) | 1992-11-06 |
| IT8822899A0 (en) | 1988-12-09 |
| FR2640256A1 (en) | 1990-06-15 |
| GB8927013D0 (en) | 1990-01-17 |
| IT1227887B (en) | 1991-05-14 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20011129 |