[go: up one dir, main page]

WO1998038132A1 - Zeolitic molecular sieve, process for its preparation and its use - Google Patents

Zeolitic molecular sieve, process for its preparation and its use Download PDF

Info

Publication number
WO1998038132A1
WO1998038132A1 PCT/EP1998/001098 EP9801098W WO9838132A1 WO 1998038132 A1 WO1998038132 A1 WO 1998038132A1 EP 9801098 W EP9801098 W EP 9801098W WO 9838132 A1 WO9838132 A1 WO 9838132A1
Authority
WO
WIPO (PCT)
Prior art keywords
molecular sieve
zeolite
sieve according
alkaline
alkali metal
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.)
Ceased
Application number
PCT/EP1998/001098
Other languages
French (fr)
Inventor
Horst Thamm
Christian Buhl
Wolfgang Lutz
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Grace GmbH
Original Assignee
Grace GmbH
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Grace GmbH filed Critical Grace GmbH
Priority to AU67259/98A priority Critical patent/AU6725998A/en
Publication of WO1998038132A1 publication Critical patent/WO1998038132A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
    • C10L3/00—Gaseous fuels; Natural gas; Synthetic natural gas obtained by processes not covered by subclass C10G, C10K; Liquefied petroleum gas
    • C10L3/06—Natural gas; Synthetic natural gas obtained by processes not covered by C10G, C10K3/02 or C10K3/04
    • C10L3/10—Working-up natural gas or synthetic natural gas
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/02—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B39/00—Compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites; Their preparation; After-treatment, e.g. ion-exchange or dealumination
    • C01B39/50—Zeolites wherein inorganic bases or salts occlude channels in the lattice framework, e.g. sodalite, cancrinite, nosean, hauynite
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
    • C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
    • C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2253/00—Adsorbents used in seperation treatment of gases and vapours
    • B01D2253/10—Inorganic adsorbents
    • B01D2253/106—Silica or silicates
    • B01D2253/108—Zeolites
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2257/00—Components to be removed
    • B01D2257/30—Sulfur compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2258/00—Sources of waste gases
    • B01D2258/06—Polluted air

Definitions

  • the invention relates to a zeolitic molecular sieve, a process for its preparation and its use for separating components from gases .
  • zeolitic molecular sieves are used in so-called dry processes for purifying gases, such as e.g. for desulphurizing natural gas. These molecular sieves separate the gaseous components according to the molecule size, adsorptive interaction energy or diffusion rate of the molecules in the micropore system. Because the capacity is markedly lower compared with absorption processes, molecular sieves are used in particular for the treatment of gases with low impurity levels, so-called lean gases.
  • zeolitic molecular sieve which is characterized in that its cavities are partially blocked.
  • the subject of the invention is furthermore a process for the preparation of a zeolitic molecular sieve with partially blocked cavities, which is characterized in that sodium silicate is reacted with sodium aluminate in aqueous medium in a Si:Al ratio in the range from 0.5 to 2.0 in the presence of from 5 to 10 wt.% of alkali metal and/or alkaline-earth metal salts which have mono- or bivalent anions, and is converted at 60 to 90°C in a manner known per se into a polycrystalline , partially blocked zeolite .
  • the subject of the invention is moreover the use of the zeolitic molecular sieve according to the invention for separating components from gases, in particular for purifying gases (in particular lean gases).
  • the formation of COS can be suppressed by the incorporation of blocking substances into the cavities of the zeolite, without this impairing the sorption process.
  • the partial blocking according to the invention of the cavities of the zeolite essentially concerns the small cavities of the zeolite, the so-called sodalite or ⁇ cages.
  • the reactants involved in the formation of COS only the water molecules can diffuse into the ⁇ cages of the zeolite.
  • there is room for two to four water molecules in one ⁇ cage for the water molecule, the stay in the ⁇ cage is greatly favoured in terms of energy, which is why it is no longer available for the reverse reaction.
  • the zeolites suitable for the partial blocking according to the invention are synthetic zeolites .
  • those of type A are preferred, in particular zeolite 4A and zeolite 5A.
  • These zeolites are preferably ion- exchanged.
  • a zeolite 5A prepared by ion exchange of zeolite 4A with Ca ions has proved to be particularly suitable.
  • All materials, except for water, which are capable of becoming deposited in the ⁇ cages of the zeolite and which do not, or only slightly, impair the sorption process are suitable for the partial blocking of the zeolitic molecular sieve.
  • Particularly suitable are alkali metal and/or alkaline-earth metal salts with mono- or bivalent anions.
  • the anions for the alkali metal and/or alkaline-earth metal salts are preferably selected from the group consisting of nitrate, nitrite, chloride, bromide, iodide, chlorate, bromate, iodate, rhodanide, cyanide, carbonate, sulphate and aluminate.
  • nitrate nitrite
  • chloride bromide, iodide, chlorate, bromate, iodate, rhodanide, cyanide, carbonate, sulphate and aluminate.
  • Nitrite, rhodanite and aluminate are particularly preferred.
  • the salts must be alkali-resistant to the extent that the salts do not decompose on synthesis of the zeolites.
  • the temperature resistance should more advantageously be at least 250 C, preferably 400 C and in particular 500°C, i.e. no substantial decomposition of the salts must take place- at these temperatures.
  • the alkali metal and/or alkaline-earth metal salt content which has become deposited for the partial blocking should be at least 1 wt . % , at most 10 wt . % and preferably 1 to 8 wt . % , relative to the total weight of the loaded molecular sieve in the dry state. Quantities of deposited salts of 1.5 to 4.0 wt . % are particularly preferred. These quantities are generally sufficient to achieve the 50 to 100% blocking of the ⁇ cages which is sought according to the invention.
  • the preparation of the zeolitic molecular sieve according to the invention can take place in various ways.
  • An effective partial blocking of the cavities of the molecular sieve takes place with the incorporation of salts during or after the synthesis of the zeolite.
  • a preferred process according to the invention for preparing zeolitic molecular sieves with partially blocked cavities consists of reacting sodium silicate with sodium aluminate in aqueous medium in a Si:Al ratio in the range from 0.5 to 2.0 in the presence of from 5 to 10 wt . % of alkali metal and/or alkaline-earth metal salts which have mono- or bivalent anions, and converting it at 60 to 90 C in a manner known per se into a polycrystalline, partially blocked zeolite.
  • the quantity of the alkali metal and/or alkaline-earth metal salts to be used relates to the weight of the synthesis mixture.
  • a zeolitic molecular sieve which is partially blocked with aluminate can be obtained directly when the aluminium component is used in excess .
  • the zeolitic molecular sieves according to the invention are in most cases used together with a binder. To that end, they are mixed in a known manner with suitable quantities of binder and processed to form suitable moulded bodies (for example granular material). Suitable inert binders are part of the state of the art and are for example montmorillonite, attapulgite and kaolinite.
  • the zeolitic molecular sieves according to the invention with partially blocked cavities are suitable for purifying gases, in particular for desulphurizing natural gas, since their use minimizes COS formation.
  • a further preferred use is the separation of methanol from gases, e.g. from the C0 2 occurring in the Rectisol process (to prevent the formation of dimethyl ether) .
  • a zeolite NaA (4A) customary in the trade was loaded with a mixture of 80% carbon dioxide and 20% hydrogen sulphide after being activated for ten hours at 400°C in a vacuum of less than 0.133 Pa (10 " torr) .
  • the loading was 5 mol of mixture per 1 kg of zeolite.
  • 78% of the hydrogen sulphide were converted into carbon oxide sulphide (COS) . Since the same quantity was found after 100 hours, the 78% correspond to the equilibrium value of the COS formation under these specific test conditions.
  • a cylindrical vessel made of polytetrafluoroethylene was half filled with a mixture consisting of 7 parts by weight of a 0.5 molar sodium silicate solution. The same quantity of a solution which was made up of 7 parts by weight of a 1.4 molar sodium aluminate solution and 0.07 mol of sodium nitrite was added to this .
  • the mixture was converted into polycrystalline zeolite NaA (4A) in the closed vessel at 80°C.
  • the material loaded with nitrite was washed with water and calcined at 400°C. It contained 3 wt . % of sodium nitrite.
  • the COS formation was 2% after five hours' contact time with the mixture of carbon dioxide/hydrogen sulphide described in Comparative Example 1, and 4.5% after 100 hours.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Materials Engineering (AREA)
  • Inorganic Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)
  • Silicates, Zeolites, And Molecular Sieves (AREA)

Abstract

A zeolitic molecular sieve is described, the cavities of which are partially blocked. This partial blocking essentially concerns the β cages which are preferably 50 to 100 % blocked. Preferred blocking agents are alkali metal and/or alkaline-earth metal salts with mono- or bivalent anions. The incorporation of these salts for partially blocking the cavities of the molecular sieve takes place during or after the synthesis of the zeolite. The zeolitic molecular sieve according to the invention is suitable for separating components from gases, in particular for purifying gases such as for example for desulphurizing natural gas.

Description

Zeolitic Molecular Sieve, Process for Its Preparation and Its Use
The invention relates to a zeolitic molecular sieve, a process for its preparation and its use for separating components from gases .
It is known that zeolitic molecular sieves are used in so-called dry processes for purifying gases, such as e.g. for desulphurizing natural gas. These molecular sieves separate the gaseous components according to the molecule size, adsorptive interaction energy or diffusion rate of the molecules in the micropore system. Because the capacity is markedly lower compared with absorption processes, molecular sieves are used in particular for the treatment of gases with low impurity levels, so-called lean gases.
When lean gases which also contain substantial quantities of carbon dioxide in addition to hydrogen sulphide are desulphurized, hydrogen sulphide is converted in the presence of carbon dioxide into carbon oxide sulphide (COS) and water in accordance with the reaction H2S + C02 "■* COS + H20. The driving force of the reaction, which as a pure gas-phase reaction with an equilibrium constant of K = 6.7 x 10" at 298° K lies on the side of the educts, is the high affinity of the reaction water to the molecular sieve. While the water is selectively adsorbed, the formed carbon oxide sulphide leaves the treatment plant with the clean gas. Unlike hydrogen sulphide, carbon oxide sulphide does not cause any stress-cracking corrosion in the absence of water, but has a toxic effect in the same manner as hydrogen sulphide and is therefore to be separated from clean gases generally.
The formation of COS is greatly accelerated by alkali ions, e.g. sodium ions. It follows that sodium-poor zeolites, e.g. highly exchanged calcium (CaNa) zeolites A, were recommended for the desulphurization of C02-containing natural gases . A completely exchanged Ca zeolite A should accordingly be COS-inert (D.M. Ruthen: Principles of Adsorption and Adsorption Processes. John Wiley & Sons, New York, 1984, p. 360). It has however been shown that when the adsorption plants are operated economically, i.e. when long sorption phases are realized, COS is also formed to a great extent with Ca zeolites A. Even though the catalytic effect can be ignored in the CaNa molecular sieve A, the equilibrium position of the reaction is always shifted to the side of the products via the selective adsorption of the reaction water. The effect increases as the C02/H2S gradient becomes steeper.
The use of zeolites loaded with heavy metal ions in accordance with DD-A-241196 and 241202 actually initially reduces the formation of COS. However, on account of the irreversible formation of heavy metal sulphides, the molecular sieves quickly suffer a loss of selectivity and even chemical stability. Moreover, ecologically damaging products occur with the spent zeolites .
In order to shift the equilibrium position of the reaction to the side of the educts, it was proposed to preload the molecular sieve with water (M.R. Cines, D.M. Haskell and C.G. Houser: Chemical Engineering Progress 72 (1972), 8, 89). This variant of COS minimization greatly shortens the break-through times of the hydrogen sulphide since the selectivity of the molecular sieve vis-a-vis H2S is considerably reduced because of the competing adsorption of the H20. Moreover, it is doubtful whether the water is homogeneously distributed over the entire molecular sieve bed.
It is the object of the invention to prepare new zeolitic molecular sieves which are suitable for purification processes and which prevent the formation of undesired components, in particular the formation of COS during gas desulphurizations , such as natural gas desulphurization.
In order to achieve this object, a zeolitic molecular sieve is proposed which is characterized in that its cavities are partially blocked.
The subject of the invention is furthermore a process for the preparation of a zeolitic molecular sieve with partially blocked cavities, which is characterized in that sodium silicate is reacted with sodium aluminate in aqueous medium in a Si:Al ratio in the range from 0.5 to 2.0 in the presence of from 5 to 10 wt.% of alkali metal and/or alkaline-earth metal salts which have mono- or bivalent anions, and is converted at 60 to 90°C in a manner known per se into a polycrystalline , partially blocked zeolite .
The subject of the invention is moreover the use of the zeolitic molecular sieve according to the invention for separating components from gases, in particular for purifying gases (in particular lean gases).
Surprisingly, the formation of COS can be suppressed by the incorporation of blocking substances into the cavities of the zeolite, without this impairing the sorption process. The partial blocking according to the invention of the cavities of the zeolite essentially concerns the small cavities of the zeolite, the so-called sodalite or β cages. For steric reasons, of the reactants involved in the formation of COS, only the water molecules can diffuse into the β cages of the zeolite. Depending on the type of cations present in the zeolite, there is room for two to four water molecules in one β cage. For the water molecule, the stay in the β cage is greatly favoured in terms of energy, which is why it is no longer available for the reverse reaction. Since, however, the β cages are blocked according to the invention, both COS and H20 are to be found in the cages, where, on account of the equilibrium constant of K = 6.7 x 10" (298° K) , they are converted again into the educts H2S and C02 immediately after their formation.
The zeolites suitable for the partial blocking according to the invention are synthetic zeolites . In addition to zeolites of type X and Y, those of type A are preferred, in particular zeolite 4A and zeolite 5A. These zeolites are preferably ion- exchanged. A zeolite 5A prepared by ion exchange of zeolite 4A with Ca ions has proved to be particularly suitable.
All materials, except for water, which are capable of becoming deposited in the β cages of the zeolite and which do not, or only slightly, impair the sorption process are suitable for the partial blocking of the zeolitic molecular sieve. Particularly suitable are alkali metal and/or alkaline-earth metal salts with mono- or bivalent anions. Alkali metal salts, in particular sodium salts, are preferred. The anions for the alkali metal and/or alkaline-earth metal salts are preferably selected from the group consisting of nitrate, nitrite, chloride, bromide, iodide, chlorate, bromate, iodate, rhodanide, cyanide, carbonate, sulphate and aluminate. However, mixtures of these anions can of course also be present. Nitrite, rhodanite and aluminate are particularly preferred.
When selecting these salts, account should be taken of their alkali resistance and temperature resistance owing to the conditions of the synthesis and calcination. The salts must be alkali-resistant to the extent that the salts do not decompose on synthesis of the zeolites. The temperature resistance should more advantageously be at least 250 C, preferably 400 C and in particular 500°C, i.e. no substantial decomposition of the salts must take place- at these temperatures.
In order to achieve an adequate partial blocking of the cavities of the zeolitic molecular sieve, the alkali metal and/or alkaline-earth metal salt content which has become deposited for the partial blocking should be at least 1 wt . % , at most 10 wt . % and preferably 1 to 8 wt . % , relative to the total weight of the loaded molecular sieve in the dry state. Quantities of deposited salts of 1.5 to 4.0 wt . % are particularly preferred. These quantities are generally sufficient to achieve the 50 to 100% blocking of the β cages which is sought according to the invention.
The preparation of the zeolitic molecular sieve according to the invention can take place in various ways. An effective partial blocking of the cavities of the molecular sieve takes place with the incorporation of salts during or after the synthesis of the zeolite. A preferred process according to the invention for preparing zeolitic molecular sieves with partially blocked cavities consists of reacting sodium silicate with sodium aluminate in aqueous medium in a Si:Al ratio in the range from 0.5 to 2.0 in the presence of from 5 to 10 wt . % of alkali metal and/or alkaline-earth metal salts which have mono- or bivalent anions, and converting it at 60 to 90 C in a manner known per se into a polycrystalline, partially blocked zeolite. The quantity of the alkali metal and/or alkaline-earth metal salts to be used relates to the weight of the synthesis mixture.
A zeolitic molecular sieve which is partially blocked with aluminate can be obtained directly when the aluminium component is used in excess .
A possible subsequent partial blocking can take place by loading with the corresponding salts from the salt melt. In practice, the zeolitic molecular sieves according to the invention are in most cases used together with a binder. To that end, they are mixed in a known manner with suitable quantities of binder and processed to form suitable moulded bodies (for example granular material). Suitable inert binders are part of the state of the art and are for example montmorillonite, attapulgite and kaolinite.
The zeolitic molecular sieves according to the invention with partially blocked cavities are suitable for purifying gases, in particular for desulphurizing natural gas, since their use minimizes COS formation. A further preferred use is the separation of methanol from gases, e.g. from the C02 occurring in the Rectisol process (to prevent the formation of dimethyl ether) .
Comparative Example 1
A zeolite NaA (4A) customary in the trade was loaded with a mixture of 80% carbon dioxide and 20% hydrogen sulphide after being activated for ten hours at 400°C in a vacuum of less than 0.133 Pa (10" torr) . The loading was 5 mol of mixture per 1 kg of zeolite. After five hours' contact time of the mixture on the zeolite, 78% of the hydrogen sulphide were converted into carbon oxide sulphide (COS) . Since the same quantity was found after 100 hours, the 78% correspond to the equilibrium value of the COS formation under these specific test conditions.
After complete exchange of the sodium ions for calcium ions, the COS formation on the now catalytically less active CaA zeolite (5A) after five hours' contact time was still only 16 vol.%. However, after 100 hours, 72% of the hydrogen sulphide had already converted into COS. A commercial NaX zeolite exhibits a COS formation of 65% after 5 hours and 76% after 100 hours.
Example 1
A cylindrical vessel made of polytetrafluoroethylene was half filled with a mixture consisting of 7 parts by weight of a 0.5 molar sodium silicate solution. The same quantity of a solution which was made up of 7 parts by weight of a 1.4 molar sodium aluminate solution and 0.07 mol of sodium nitrite was added to this .
The mixture was converted into polycrystalline zeolite NaA (4A) in the closed vessel at 80°C. The material loaded with nitrite was washed with water and calcined at 400°C. It contained 3 wt . % of sodium nitrite.
After five hours' contact time with the mixture of carbon dioxide/hydrogen sulphide described in Comparative Example 1, a COS formation of 2.5 vol . % was analysed. After 100 hours, the COS formation was 7 vol . % .
Example 2
7 parts by weight of a 0.5 molar sodium silicate solution and 1 part by weight of triethanolamine were mixed with a mixture of 7 parts by weight of a 1.4 molar sodium aluminate solution, 1 part by weight of triethanolamine and 0.07 mol of sodium rhodanide and stirred for a short time. The gel obtained was converted into polycrystalline zeolite NaA (4A) at 80°C . The subsequent procedure was as in Example 1. The quantity of deposited sodium rhodanide was 1 wt . % .
After five hours' contact time with the mixture of carbon dioxide/hydrogen sulphide described in Comparative Example 1, the COS formation was 1.5 vol.%, and after 100 hours 5.5 vol.%. Example 3
7 parts by weight of a 0.5 molar sodium silicate solution were intimately mixed_ with 7 parts by weight of a 0.7 molar sodium aluminate solution with addition of 0.07 mol of sodium nitrite and converted into polycrystalline zeolite NaX at 80 °C. The subsequent procedure was as in Example 1. The loading with sodium nitrite was 6 wt . % .
The COS formation was 2% after five hours' contact time with the mixture of carbon dioxide/hydrogen sulphide described in Comparative Example 1, and 4.5% after 100 hours.
Comparison of the above examples with Comparative Example 1 shows that a markedly reduced, minimized COS formation is to be observed after partial blocking of the cavities of the zeolite with salts.

Claims

Patent claims
1. Zeolitic molecular sieve, characterized in that its cavities are partially blocked.
2. Molecular sieve according to Claim 1 wherein the cavities are partially blocked by a material, except for water, which is capable of becoming deposited in the β cages of the zeolite.
3. Molecular sieve according to Claim 1 or 2 wherein 50 to 100% of the β cages are blocked.
4. Molecular sieve according to one of Claims 1 to 3 wherein the cavities are partially blocked by alkali metal and/or alkaline-earth metal salts with mono- or bivalent anions .
5. Molecular sieve according to Claim 4 wherein the alkali metal and/or alkaline-earth metal salts are alkali- resistant and temperature-resistant up to 250°C, preferably up to 500°C.
6. Molecular sieve according to Claim 4 or 5 wherein the alkali metal salts are sodium salts.
7. Molecular sieve according to one of Claims 4 to 6 wherein the anions of the alkali metal and/or alkaline-earth metal salts are selected from the group consisting of nitrate, nitrite, chloride, bromide, iodide, chlorate, bromate, iodate, rhodanide, cyanide, carbonate, sulphate, aluminate and mixtures of two or more of these anions.
8. Molecular sieve according to one of Claims 4 to 7 which contains at least 1 wt . % of alkali metal and/or alkaline- earth metal salts, relative to the total weight in the dry state .
9. Molecular sieve according to Claim 8 which contains 1 to 8 wt . % of alkali metal and/or alkaline- earth metal salts.
10. Molecular sieve according to Claim 9 which contains 1.5 to 4 wt . % of alkali metal and/or alkaline-earth metal salts.
11. Molecular sieve according to one of Claims 1 to 10 which is a zeolite X or a zeolite A, in particular a zeolite 4A or a zeolite 5A.
12. Molecular sieve according to Claim 11 which is an ion- exchanged zeolite A, in particular an ion-exchanged zeolite 4A or zeolite 5A.
13. Molecular sieve according to Claim 12 which is a zeolite 5A prepared by ion exchange of zeolite 4A with Ca ions .
14. Molecular sieve according to one of Claims 1 to 13 which is mixed with a binder.
15. Process for the preparation of a zeolitic molecular sieve with partially blocked cavities according to one of Claims 1 to 13, characterized in that sodium silicate is reacted with sodium aluminate in aqueous medium in a Si:Al ratio in the range from 0.5 to 2.0 in the presence of from 5 to 10 wt . % of alkali metal and/or alkaline-earth metal salts which have mono- or bivalent anions, and is converted at 60 to 90 °C in a manner known per se into a polycrystalline, partially blocked zeolite.
16. Use of the zeolitic molecular sieve according to one of Claims 1 to 14 or prepared in accordance with the process according to Claim 15 for separating components from gases, in particular for purifying gases.
17. Use according to Claim 16 for desulphurizing gas, in particular for desulphurizing natural gas, or for separating jnethanol from gases, in particular from C02.
PCT/EP1998/001098 1997-02-28 1998-02-27 Zeolitic molecular sieve, process for its preparation and its use Ceased WO1998038132A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU67259/98A AU6725998A (en) 1997-02-28 1998-02-27 Zeolitic molecular sieve, process for its preparation and its use

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19708085.5 1997-02-28
DE1997108085 DE19708085A1 (en) 1997-02-28 1997-02-28 Zeolitic molecular sieve, process for its production and its use

Publications (1)

Publication Number Publication Date
WO1998038132A1 true WO1998038132A1 (en) 1998-09-03

Family

ID=7821789

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP1998/001098 Ceased WO1998038132A1 (en) 1997-02-28 1998-02-27 Zeolitic molecular sieve, process for its preparation and its use

Country Status (3)

Country Link
AU (1) AU6725998A (en)
DE (1) DE19708085A1 (en)
WO (1) WO1998038132A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3816341A (en) * 1972-04-17 1974-06-11 Union Carbide Corp Crystalline metal aluminosilicates having halide and certain other salts irreversibly occluded therein
US4333859A (en) * 1980-10-27 1982-06-08 W. R. Grace & Co. High silica faujasite polymorph - CSZ-3 and method of synthesizing
DE4042002A1 (en) * 1990-12-22 1991-05-23 Buhl Josef Christian Dr Carbon di:oxide removal from waste gas - by chemical reaction with porous solid basic nitrite-sodalite

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3816341A (en) * 1972-04-17 1974-06-11 Union Carbide Corp Crystalline metal aluminosilicates having halide and certain other salts irreversibly occluded therein
US4333859A (en) * 1980-10-27 1982-06-08 W. R. Grace & Co. High silica faujasite polymorph - CSZ-3 and method of synthesizing
DE4042002A1 (en) * 1990-12-22 1991-05-23 Buhl Josef Christian Dr Carbon di:oxide removal from waste gas - by chemical reaction with porous solid basic nitrite-sodalite

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
GURRIS, CH. ET AL: "Synthesis and properties of zeolite A with salt-containing.beta.-cages", STUD. SURF. SCI. CATAL. (1995), 98(ZEOLITE SCIENCE 1994: RECENT PROGRESS AND DISCUSSIONS), 46-7 CODEN: SSCTDM;ISSN: 0167-2991, 1995, XP002069552 *
JOSEF-CHRISTIAN BUHL & AL.: "Synthesis and crystal structure of nitrate enclathrated sodalite Na8(AlSiO4)6(NO3)2", JOURNAL OF ALLOYS AND COMPOUNDS., vol. 235, LAUSANNE CH, pages 41 - 47, XP002068458 *
SACHTLER W M H ET AL: "GENESIS AND CHARACTERIZATION OF TRANSITION METAL CLUSTERS IN Y ZEOLITES", SOLID STATE IONICS FEB-MAR 1988, vol. 26, no. 2, February 1988 (1988-02-01), pages 71 - 76, XP002067799 *
SEIDEL A ET AL: "Na solid state MAS NMR of sodium halides occluded in zeolites", SOLID STATE NUCL MAGN RESON;SOLID STATE NUCLEAR MAGNETIC RESONANCE DEC 1997 ELSEVIER SCI B.V., AMSTERDAM, NETHERLANDS, vol. 9, no. 2-4, December 1997 (1997-12-01), pages 129 - 141, XP002067800 *

Also Published As

Publication number Publication date
AU6725998A (en) 1998-09-18
DE19708085A1 (en) 1998-09-03

Similar Documents

Publication Publication Date Title
US4474896A (en) Adsorbent compositions
US5916836A (en) Method of manufacture of molecular sieves
US6652626B1 (en) Agglomerated adsorbent, process for the production thereof and use thereof for the non-cryogenic separation of industrial gases
EP1148025B1 (en) Method for purifying hydrogen-based gas mixture
EP2368849B2 (en) Chabazite-type zeolite and process for producing the same
CA2085180C (en) Nitrogen adsorption with a ca and/or sr exchanged lithium x-zeolite
US6530975B2 (en) Molecular sieve adsorbent for gas purification and preparation thereof
US4000248A (en) Synthesis of zeolites
US5919287A (en) Process for the purification of a solution of lithium salts contaminated by metallic cations and use of this process in the production of zeolites exchanged with lithium
US5891415A (en) Process for selective oxidation of hydrogen sulfide to elemental sulfur
JPH10212103A (en) Improvement of pressure swing adsorption psa method in purification of hydrogen
GB2109359A (en) Preparation of binderless 3a zeolite adsorbents
ES2232400T3 (en) ZEOLITAS X EXCHANGED SPECIFICALLY WITH LITHIUM, ITS PREPARATION PROCEDURE AND ITS USE WITH NITROGEN ADSORBENTS IN THE SEPARATION OF AIR GASES.
US4976944A (en) Purification of silane gas
US5369070A (en) Zeolite Y-based catalytic composition which can be used in treating oxygenated effluent containing nitrogen oxides, its preparation and process for use
US6583081B2 (en) Method of manufacture of molecular sieves
US6407025B1 (en) Method of manufacture of multicationic molecular sieves
EP0023089A1 (en) Method of preparing zeolite ZSM-48, the zeolite so prepared and its use as catalyst for organic compound conversion
WO1998038132A1 (en) Zeolitic molecular sieve, process for its preparation and its use
US6136069A (en) Zincoaluminosilicates of the FAU structure
US5219545A (en) Catalyst and method for catalytically decomposing nitrogen oxides
JPH07185326A (en) Adsorbent for purification of hydrocarbons in exhaust gas
JP2001347123A (en) Carbon dioxide adsorption separation method
JPH0796175A (en) Adsorbent
US5756064A (en) Siliceous offretite

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE GH GM GW HU ID IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT UA UG US UZ VN YU ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW SD SZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: CA

122 Ep: pct application non-entry in european phase