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GB2038301A - Process for the production of zeolite A - Google Patents

Process for the production of zeolite A Download PDF

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Publication number
GB2038301A
GB2038301A GB7940829A GB7940829A GB2038301A GB 2038301 A GB2038301 A GB 2038301A GB 7940829 A GB7940829 A GB 7940829A GB 7940829 A GB7940829 A GB 7940829A GB 2038301 A GB2038301 A GB 2038301A
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Prior art keywords
solution
zeolite
process according
na2o
sodium silicate
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GB2038301B (en
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Produits Chimiques Ugine Kuhlmann
Ugine Kuhlmann SA
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Produits Chimiques Ugine Kuhlmann
Ugine Kuhlmann SA
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    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B33/00Silicon; Compounds thereof
    • C01B33/20Silicates
    • C01B33/26Aluminium-containing silicates, i.e. silico-aluminates
    • C01B33/28Base exchange silicates, e.g. zeolites
    • C01B33/2807Zeolitic silicoaluminates with a tridimensional crystalline structure possessing molecular sieve properties; Isomorphous compounds wherein a part of the aluminium ore of the silicon present may be replaced by other elements such as gallium, germanium, phosphorus; Preparation of zeolitic molecular sieves from molecular sieves of another type or from preformed reacting mixtures
    • C01B33/2815Zeolitic silicoaluminates with a tridimensional crystalline structure possessing molecular sieve properties; Isomorphous compounds wherein a part of the aluminium ore of the silicon present may be replaced by other elements such as gallium, germanium, phosphorus; Preparation of zeolitic molecular sieves from molecular sieves of another type or from preformed reacting mixtures of type A (UNION CARBIDE trade name; corresponds to GRACE's types Z-12 or Z-12L)
    • C01B33/2823Zeolitic silicoaluminates with a tridimensional crystalline structure possessing molecular sieve properties; Isomorphous compounds wherein a part of the aluminium ore of the silicon present may be replaced by other elements such as gallium, germanium, phosphorus; Preparation of zeolitic molecular sieves from molecular sieves of another type or from preformed reacting mixtures of type A (UNION CARBIDE trade name; corresponds to GRACE's types Z-12 or Z-12L) from aqueous solutions of an alkali metal aluminate and an alkali metal silicate excluding any other source of alumina or silica

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Inorganic Chemistry (AREA)
  • Silicates, Zeolites, And Molecular Sieves (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Abstract

A process for the semicontinuous production of zeolite A of constant and homogeneous quality, which process comprises mixing a solution of sodium aluminate and a solution of sodium silicate instantaneously and continuously in a container and in such a manner that the average retention time in the container is from 30 seconds to 20 minutes thereby to form a gel which is subsequently crystallised in discontinuous fashion. Zeolite A prepared by the process has narrow particle size distribution with range 1-10 microns and ion exchange capacity greater than 110 mg Ca<2+>/g dry product.

Description

SPECIFICATION Process for the production of zeolite A This invention relates to the preparation of zeolite A by a semi-continuous process.
The applications of zeolites are based on their well known properties as cation exchangers, which are described for example in the "Comprehensive Treatise on Inorganic and Theoretical Chemistry" by J.W.
Mellor, vol. VI, Part 2, Longman Editors 1925, p. 575-579, and particularly on the possibility of exchanging the sodium atoms they container for calcium ions.
The most frequently used zeolite is zeolite A, of the formula Na2O, Awl203,2 SiO2, x H2O, wherein x may vary from 1 to 8 depending on the drying conditions of the product, the most commonly used products corresponding to x = 4 to 5.
To promote the Ca++ exchanging properties and selectivity of the zeolite, the zeolite should be as pure as possible and hence should be thoroughly crystallised, with any impurity being either inactive or less selective.
Also, when this zeolite is incorporated in a washing powder, it is essential that the particle size distribution should be such that the particle sizes fall close to a median diameter of 2 to 3 microns, which is small enough to prevent the product from being retained in the fibres of the textile, but large enough to permit easy solid/liquid separation during production.
The synthesis and the ion exchange properties of synthetic zeolites, and particularly zeolite A, have been well known for many years (see "lon exchange" by Friedrich Helfferich, 1962, McGraw-Hill Book Company, Chapter 2, pages 10-16).
The synthesis processes are all carried out discontinuously by mixing the elements Si, Al and Na, added in various forms, to obtain a silicoaluminate gel which is precipitated. This gel is then crystallised into zeolite A by being matured in the mother liquor containing a quantity of free soda and soluble alumina which is compatible with the type of zeolite obtained. Such processes are described, for example, in U.S. Patents Nos.
2,841,471 and 2,847,280, French Patent No. 1,404,467, B.E. 813,581 and German Auslegeschrift No. 2,517,218.
These discontinuous precipitations lead to substantial variations in the Na2O, Al203 and SiO2 contents of the liquor obtained from the mixture. This results in considerable lack of uniformity of the resultant product particularly as regards its particle size, crystallinity and exchange selectivity (pore size).
An entirely continuous method of production described in British Patent Application No.31453/78 (Serial No. 2001614) enables sodium silicoaluminate gel to be prepared from a mixture having a constant composition, but the disadvantage of this process is that a relatively large number of maturing vats, arranged in cascade, are required in order to avoid short-circuiting of a certain proportion of freshly precipitated gel and thereby to obtain the desired particle size.
We have now discovered and perfected a process for producing zeolite which remedies the various problems encountered earlier.
Accordingly, the present invention provides a process for the semicontinuous production of zeolite A of constant and homogeneous quality, which process comprises mixing a solution of sodium aluminate and a solution of sodium silicate instantaneously and continuously in a container and in such a manner that the average retention time in the container is from 30 seconds to 20 minutes thereby to form a gel which is subsequently crystallised in discontinuous fashion.
Thus the present process involves preparing, by instantaneous precipitation, a sodium silicoaluminate gel from solutions of sodium silicate and sodium aluminate which are mixed simultaneously and continuously by rnQâns of suitable apparatus. The quality of the product obtained depends on the quality of continuous production of this mixture.
The mixing of the solutions has to be carried out rapidly and must be effective enough to ensure that at no time is there a localised excess of silica in relation to the alumina (the number of moles of Al203 should be 2 moles of SiO2). An excess of silica, even a momentary one, would to a deterioration in the quality of the product, by initiating precipitation and crystallisation of a silicoaluminate other than zeolite A.
Mixing is carried out continuously in a reactor fitted with a stirrer system which permits instantaneous homogenisation, such as a turbine or any other suitable means. The capacity of this reactor is designed to give an average retention time of from 30 seconds to 20 minutes, which is essential to ensure complete formation of the gel.
The addition of the two reaction solutions, whose flow rates are regulated, takes place in the zone of strong suction created by the turbine. The action of this turbine is further increased if it is placed in an enclosure which is fixed or rotates at the same time as the turbine.
This enclosure consists of two saucer-like plates the concavity of which is directed towards the turbine.
These two plates enclose a volume into which the two reaction solutions are injected or sucked.
The resultant sodium silicoaluminate gel is decanted by overflowing into a second reactor fitted with a stirrer and maintained at a constant temperature within a range of from 75 to 1 00'C to enable crystallisation of the desired zeolite A. This crystallisation thus occurs discontinuously, the advantage of this being that the level of crystallinity required and the particle size of the end product can be adjusted at will by varying the period of the end product can be adjusted at will by varying the period of maturing and the stirring conditions.
The continuous preparation of the sodium silicoaluminate gel may be effected using, for example, sodium aluminate solutions characterised by a molar ratio of Al2O3/Na2O of from 0.3 to 0.8, and of H2O/Na2O of from 5 to 150, these solutions being obtained either by attacking hydrated alumina with a sodium hydroxide solution or by taking them from a Bayer cycle for the production of alumina, and sodium silicate solutions characterised by a molar ratio of S iO2/Na2O of from 2 to 3.5 and of H2O/Na2O of from 25 to 100. These solutions may be prepared from raw silicon materials and soda materials which may vary depending upon availability and cost.Examples of such materials are industrial sodium silicate in powder form, industrial sodium silicate Iyes, silica contained in sand and soda, soda or silica gel recovered from the fluosilicic acid residue from a plant for the production of aluminium fluoride or hydrofluoric acid, or recovered from a treatment plant for the gases released during the treatment of natural phosphates, sodium silicate obtained from a plant for the desilication of bauxites before treatment in alumina-producing factories, residual silica obtained in the manufacture of aluminium salts by a wet attack on natural silicoaluminates such as kaolin or clays, and silica obtained thermally, e.g. in the production of magnesium, silicon-metal or silicon alloys.
The mixture obtained by the addition of these sodium aluminate and silicate solutions should have a molar ratio of Al203/SiO2 of from 0.5 to 1.2 and the Na2O content should be adjusted so that the soda concentration of the liquor in which crystallisation is carried out after precipitation is not more than 135 of NaOH per litre, so as to avoid the crystallisation of silicoaluminates of the inactive feldspar type, and is not less than 26 of NaOH per litre to ensure that the rate of crystallisation of the zeolite A is compatible with industrial production. After the sodium silicoaluminate gel prepared as described above has been matured, a suspension of crystallised zeolite A is obtained which is separated from its mother liquors by any suitable method of solid/liquid separation (decanting, filtering, etc), then washed and dried.
The zeolite A produced by the process described above has the following characteristics: (a) a narrow distribution of particle size, 90% of the particles having a particle size with a 4u range for a median diameter of from 1 to 1 lOu, the median diameter being varied according to the intended use of the zeolite.
(b) an ion exchange capacity greaterthan 110 mg ofCa++/g of dry product.
The zeolite A thus obtained is particularly suitable for use in washing powders in order to soften hard water.
The following Examples illustrate the invention.
Example 1 By attacking hydrated alumina with a soda solution at 100 , a solution A of sodium aluminate is obtained, containing 54.3 g of Al203 and 81.1 g of Na2O per litre (i.e. ratios of Al203/Na2O and H20/Na2O of 0.40 and 42, respectively).
By dissolving powdered industrial-grande sodium silicate in water, a solution B of sodium silicate is obtained, containing 137.4 g SlO2 and 47.2 g of Na2O per litre (i.e. ratios of SiO2/Na2O and H2O/Na2O of 3 and 69, respectively).
A sodium silicoaluminate gel is prepared, with a ratio of Al203/SiO2 of 0.6, by simultaneously passing 0.86 1 of solution A of 0.344 1 of solution B into a reactor of the type described above, at a temperature of 90 C, the volume of which is designed to give an average retention time of 45 seconds. The gel thus obtained is decanted by overflowing into the maturing reactor. This operation is continued for 10 minutes. Then the maturing of the gel thus obtained is carried out in this latter reactor, which is maintained at a temperature of 90"C and fitted with a stirrer enabling the zeolite to be kept effectively in suspension during the crystallisation process.
After 6 hours of maturing, the zeolite is separated from the mother liquors by filtration, then washed and dried in an oven at 900C. 140 g of product are obtained, the X-ray diffraction diagram of which is that of crystalline zeolite A. The particle size ranges from 1.5 to 10 with an average diameter of 2.9.
The Ca++ ion sequestering power is 115 mg of Ca per gram of anhydrous product and the zeolite A obtained has the following particle size distribution curve: Proportion (% by weight) Diameter (in microns) 2 1.5 10 1.9 25 2.35 50 2.9 75 3.7 90 4.6 98 6 Example 2 The solution A of sodium aluminate is prepared as before by attacking hydrated alumina with a sodium hydroxide solution and contains 53 g of Awl203 and 79 g of Na2O per litre (i.e. ratios of Al203/Na2O and H2O/Na2O of 0.40 and 44, respectively).
The solution B of sodium silicate is prepared from a silica known as ex H2SiF6 which has the advantage of being very cheap as it is a residue from an aluminium fluoride producing plant. This highly reactive silica can easily be attacked by a NaOH solution at 100"C and yields a sodium silicate solution containing 127.9 g of SiO2 and 37.8 g of Na2O per litre (i.e. ratios to SiO2/Na2O and H20/Na2O of 3.5 and 88, respectively).
0.781 of solution A and 0.313 1 of solution B are treated by the method described in Example 1. The final zeolite A obtained has a sequestering power of 111 mg of Ca++/gram of anhydrous product and a particle size of from 3 to 15 u with an average diameter of 6 u; the particle size distribution thereof being: Proportion (% by weight) Diameter (in microns) 2 4 10 5 25 6 50 7.2 75 8.8 90 10.5 98 15 Example 3 A solution of sodium aluminate consisting of a solution known as "clear from 1 st washer", taken from an alumina production unit working on the Bayer principle. This solution contains 59 g of A1203 and 62.1 g of Na2O per litre (i.e. ratios of Al203/Na2O and H20/Na2O of 0.58 and 56, respectively).
1.2701 of solution A and 0.4101 of solution B (corresponding to a ratio of Al203/SiO2 of 0.8 in the final reaction mixture) are treated by the method described in Example 1. The final zeolite A obtained has a sequestering power of 120 mg of Cat+ per gram of anhydrous product and a particle size of from 2 to 8 u with an average diameter of 4.8 Ft, the particle size distribution thereof being: Proportion (% by weight) Diameter (in microns) 2 2.6 10 3.3 25 4 50 4.7 75 6 90 7 98 9 Example 4 A solution A of sodium aluminate is prepared from a solution known as the "decomposed liquor" taken from a Bayer alumina producing unit. This solution contains 98.3 g of Al203 and 165.5 g of Na2O per litre (i.e.
ratios of Al203/Na2O and H20/Na2O of 0.36 and 21, respectively.
The solution B of sodium silicate is identical to that described in Example 3.
1.220 1 of solution A and 0.430 1 of solution B (corresponding to a ratio of Al203/SiO2 of 0.8 in the final reaction mixture) are treated according to the method described in Example 1. The final zeolite A obtained has a sequestering power of 120 mg of Ca++ per gram of anhydrous product and a particle size of from 2 to 10 with an average diameter of 4.7; the particle size distribution thereof being: Proportion (% by weight) Diameter (in microns) 2 2.6 10 3.3 25 4 50 4.7 75 6 90 7 98 9 Example 5 A solution A was prepared as described in Example 1 from hydrated alumina and sodium hydroxide solution and contains 55 g/l of Awl203 and 77 g/l of Na2O (i.e. ratios of Al203/Na2O and H20/Na2O of 0.43 and 63 respectively).
Solution B was prepared by dissolving industrial grade sodium silicate in water and contains 138 g/l of SlO2 and 42 g/l of Na2O (i.e. ratios of SiO2INa2O and H2O/Na2O of 3.4 and 78 respectively).
A sodium silicoaluminate gel is prepared, having a ratio of Al203/SiO2 of 1.1, by simultaneously passing 127 1 of solution A and 27 1 of solution B at a temperature of 90"C into a reactor of the type described above, the volume of which is designed to give an average retention time of 4 minutes. The gel thus obtained is decanted by overflowing into the maturing reactor. This operation is continued for 90 minutes.
The gel thus obtained is then matured, and after 6 hours' maturing at 90"C, with stirring, the zeolite is filtered, washed and dried.
11 kg of zeolite A are obtained, with a sequestering power of 120 mg of Ca++ per g of anhydrous product and a particle size of from 1.5 to 15 with an average diameter of 3; and a particle size distribution as follows: Proportion (% by weight) Diameter (in microns) 2 1 10 1.5 25 2 50 2.8 75 3.8 90 5 98 7

Claims (14)

1. A process for the semicontinuous production of zeolite A of constant and homogeneous quality, which process comprises mixing a solution of sodium aluminate and a solution of sodium silicate instantaneously and continuously in a container and in such a manner that the average retention time in the container is from 30 seconds to 20 minutes thereby to form a gel which is subsequently crystallised in discontinuous fashion.
2. Process according to Claim 1, wherein the aluminate solution is taken from an alumina-producing factory.
3. Process according to Claim 1 or 2, wherein the aluminate solution is saturated with alumina at atmospheric pressure.
4. Process according to Claim 1,2 or 3, wherein the sodium silicate solution is prepared from industrial sodium silicates.
5. Process according to Claim 1, 2 or 3, wherein the sodium silicate solution is prepared from silica recovered from fluosilicic acid.
6. Process according to Claim 1,2 or 3, wherein the sodium silicate solution is prepared from residual silica obtained in the wet acidic treatment of natural silicoaluminates.
7. Process according to Claim 1, 2 or 3, wherein the sodium silicate solution is prepared from silica obtained thermally, such as from the production of magnesium, silicon-metal or silicon alloys.
8. Process according to any one of the preceding claims, wherein the sodium aluminate solution is one having a molar ratio of Al203/Na2O of from 0.3 to 0.8, and of H2O/Na2O of from 5 to 150.
9. Process according to any one of the preceding claims, wherein the sodium silicate solution is one having a molar ratio of SiO2/Na2O of from 2 to 3.5, and of H2O/Na2O of from 25 to 100.
10. Process according to any one of the preceding claims wherein the mixture of sodium aluminate and sodium silicate solutions has a molar ratio of Al203/SiO2 of from 0.5 to 1.2.
11. Process according to any one of the preceding claims, wherein the Na2O content of the mixture of solutions is adjusted so that the soda concentration of the liquor in which crystallisation is performed is from 26 to 135g NaOH per litre.
12. Process according to Claim 1 substantially as hereinbefore described in any one of the Examples.
13. Zeolite A prepared according to the process of Claim 1, and having a narrow particle size distribution, 95% of the particles having a diameter within a range of from 2 to 10, the zeolite having a sequestering power for Ca++ ions which is greater than or equal to 110 mg of Ca per gram of anhydrous zeolite.
14. Zeolite A according to Claim 13 substantially as hereinbefore described.
GB7940829A 1978-12-15 1979-11-26 Process for the production of zeolite a Expired GB2038301B (en)

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FR7835344A FR2444005A1 (en) 1978-12-15 1978-12-15 INDUSTRIAL PROCESS FOR THE SEMI-CONTINUOUS MANUFACTURE OF ZEOLITE A

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DE (1) DE2950086A1 (en)
DK (1) DK532479A (en)
ES (1) ES486941A0 (en)
FI (1) FI793923A (en)
FR (1) FR2444005A1 (en)
GB (1) GB2038301B (en)
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HU (1) HU181898B (en)
IT (1) IT1119601B (en)
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WO2013188431A1 (en) 2012-06-11 2013-12-19 ZS Pharma, Inc. Production of improved microporous zirconium silicate
US8802152B2 (en) 2011-02-11 2014-08-12 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
WO2014011876A3 (en) * 2012-07-11 2015-07-16 ZS Pharma, Inc. Zirconium silicate for treatment of hyperkalemia
WO2016134277A1 (en) * 2015-02-20 2016-08-25 Usalco, Llc Stable concentrated polyaluminum chlorosilicate solutions
US9592253B1 (en) 2015-10-14 2017-03-14 ZS Pharma, Inc. Extended use zirconium silicate compositions and methods of use thereof
US9913860B2 (en) 2012-10-22 2018-03-13 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US10695365B2 (en) 2012-10-22 2020-06-30 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6049130B2 (en) * 1980-12-27 1985-10-31 日本化学工業株式会社 Manufacturing method of A-type zeolite
DK164097C (en) * 1982-09-20 1992-10-05 Tosoh Corp PROCEDURE FOR THE MANUFACTURE OF ZEOLITES
DE3926400A1 (en) * 1988-08-12 1990-02-22 Degussa Sodium A zeolite with small particle size - used as phosphate substitute and in liq. washing compsn.
EP0490011B1 (en) * 1990-12-14 1994-09-07 Foret, S.A. A process to obtain zeolite 4A starting from bauxite

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1280877A (en) * 1961-01-14 1962-01-08 Socony Mobil Oil Co Process for preparing crystalline zeolites
GB1115489A (en) * 1964-07-31 1968-05-29 Deputy Minister A process to manufacture crystalline synthetic zeolites for use as molecular sieves
US3425800A (en) * 1967-10-05 1969-02-04 Aluminum Co Of America Production of crystalline zeolites
AT322511B (en) * 1970-06-15 1975-05-26 Martinswerk G M B H Fuer Chem PROCESS FOR THE DIRECT MANUFACTURING OF A PURE CRYSTALLINE ZEOLITHIC MOLECULAR SCREEN WITH A PORE WIDTH OF 4Å.
DD107428B3 (en) * 1973-11-05 1992-12-10 Chemie Ag Bittrfeld Wolfen METHOD AND DEVICE FOR PRODUCING SYNTHETIC ZEOLITE
DE2447021C3 (en) * 1974-10-02 1984-03-22 Degussa Ag, 6000 Frankfurt Type A crystalline zeolite powder and the process for its preparation
DE2651384C2 (en) * 1976-11-11 1984-03-15 Degussa Ag, 6000 Frankfurt Process for processing waste dusts containing silicon dioxide into crystalline zeolitic molecular sieves of type A.
DE2651445A1 (en) * 1976-11-11 1978-05-18 Degussa TYPE A II CRYSTALLINE ZEOLITE POWDER

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US10398730B2 (en) 2011-02-11 2019-09-03 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US9844567B2 (en) 2011-02-11 2017-12-19 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US8808750B2 (en) 2011-02-11 2014-08-19 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US10335432B2 (en) 2011-02-11 2019-07-02 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US9861658B2 (en) 2011-02-11 2018-01-09 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US10413569B2 (en) 2011-02-11 2019-09-17 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US8802152B2 (en) 2011-02-11 2014-08-12 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US9457050B2 (en) 2011-02-11 2016-10-04 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US11406662B2 (en) 2011-02-11 2022-08-09 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US9662352B2 (en) 2011-02-11 2017-05-30 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
CN104619639B (en) * 2012-06-11 2018-02-09 Zs制药公司 The production of improved micropore zirconium silicate
US9943637B2 (en) 2012-06-11 2018-04-17 ZS Pharma, Inc. Microporous zirconium silicate and its method of production
CN104619639A (en) * 2012-06-11 2015-05-13 Zs制药公司 Production of improved microporous zirconium silicate
WO2013188431A1 (en) 2012-06-11 2013-12-19 ZS Pharma, Inc. Production of improved microporous zirconium silicate
US9707255B2 (en) 2012-07-11 2017-07-18 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia in hypercalcemic patients and improved calcium-containing compositions for the treatment of hyperkalemia
CN104968336A (en) * 2012-07-11 2015-10-07 Zs制药公司 Microporous zirconium silicate for the treatment of hyperkalemia in hypercalcemic patients and improved calcium-containing compositions for the treatment of hyperkalemia
WO2014011876A3 (en) * 2012-07-11 2015-07-16 ZS Pharma, Inc. Zirconium silicate for treatment of hyperkalemia
US9913860B2 (en) 2012-10-22 2018-03-13 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US10695365B2 (en) 2012-10-22 2020-06-30 ZS Pharma, Inc. Microporous zirconium silicate for the treatment of hyperkalemia
US11053143B2 (en) 2015-02-20 2021-07-06 Usalco, Llc Stable concentrated polyaluminum chlorosilicate solutions
WO2016134277A1 (en) * 2015-02-20 2016-08-25 Usalco, Llc Stable concentrated polyaluminum chlorosilicate solutions
US10300087B2 (en) 2015-10-14 2019-05-28 ZS Pharma, Inc. Extended use zirconium silicate compositions and methods of use thereof
US11738044B2 (en) 2015-10-14 2023-08-29 ZS Pharma, Inc. Extended use zirconium silicate compositions and methods of use thereof
US9592253B1 (en) 2015-10-14 2017-03-14 ZS Pharma, Inc. Extended use zirconium silicate compositions and methods of use thereof

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YU296179A (en) 1983-01-21
IT1119601B (en) 1986-03-10
GB2038301B (en) 1983-02-09
FR2444005A1 (en) 1980-07-11
GR66001B (en) 1981-01-13
IT7969413A0 (en) 1979-12-14
SE7910247L (en) 1980-06-16
CH641128A5 (en) 1984-02-15
CA1142501A (en) 1983-03-08
NO794092L (en) 1980-06-17
FR2444005B1 (en) 1984-05-11
ES8101516A1 (en) 1980-12-16
BR7908222A (en) 1980-07-22
PL125174B1 (en) 1983-04-30
HU181898B (en) 1983-11-28
FI793923A (en) 1980-06-16
JPS5585416A (en) 1980-06-27
PT70474A (en) 1979-12-01
RO78900A (en) 1982-12-06
PL220420A1 (en) 1980-10-06
BE880533A (en) 1980-06-11
DK532479A (en) 1980-06-16
LU81989A1 (en) 1981-07-23
DE2950086A1 (en) 1980-06-19
ES486941A0 (en) 1980-12-16

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