FI69823B - SODIUM ALUMOSILICATEEZOLE AND FAR OIL DESSION FRAMSTAELLNING OCH DESS ANVAENDNING - Google Patents

Description

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(51) Kv.4l.4 / lnt.CI.4 C 01 B 33/28 SUOMI_FINLAND (21) Patent application - Patenunsökning 79397 ** (22) Application date - Ansöknlngsdag 18.12.79 (23) Starting date - Giltlghetsdag 1 8.1 2.79 (41) ) Made public - Blivit offentlig 21 06 80

National Board of Patents and Registration Date of publication and publication. - ,, ,, ο,

Patent Application for Public Employment and Public Use of Publications L * 0 ^ (32) (33) (31) Privilege claimed - Begärd priority 20.12.78, 25.10.79, 21.11.79 USA (US) 971584, 088243, 0933 ^ 5 (71) JM Huber Corporation, Navesink ε River Road, Locust, New Jersey, USA (72) John Andrew Kostinko, Bel Air, Maryland, USA (7 * 0 Oy Kolster Ab (5 * 0 Sodium aluminosilicate zeolite A, process for its preparation and its use - Sodium aluminosilicate zeolite A, for use in the preparation and use of sodium

The present invention relates to zeolite A having a small and uniform particle size and a high magnesium exchange capacity, produced by the reaction of sodium licalate and sodium ion, to its preparation and use.

Naturally occurring hydrated metal-aluminum alumicates are called zeolites and are well known in the art of synthetic absorbents. The most common of these zeolites are sodium alumoseolites. The alloys basically comprise a three-dimensional backbone of SiO 2 and A 10 () tetrahedra. The tetrahedra are cross-linked with common oxygen atoms so that the ratio of oxygen atoms to the total number of aluminum and silicon atoms is two, i.e. ϋ / (Al + Si) = 2. The electric valence of each aluminum-containing tetrahedron is balanced by incorporating a cation, e.g. sodium ion.

This equilibrium can be expressed by the formula Al ^ / Na, ^ = 1. Water molecules in the germinating tetrahedra state of happiness dehydrate. Lice o fc products are known in the art as ueol i i 't i A, seol j.i tti X and zeolite Y.

The alloy Λ, X and Y can be distinguished and identified from other alloys based on the physical properties of the compounds and their properties. Kcostu- π ·. and density are among the properties found to be important in the identification of these alloy pathways.

The basic formula of all crystalline Natasi urnseolites can be represented as follows:

Ka ^ O: A1,; 03: xSiO2yH2C

where the values of x ia v in rr are in a given range. Tract'/)'! the x-ar-vo of the alloy connector is as much as the hip, because the aluminum tower L and the pi latinini t occupy o fly big s ti equival light stations in the crystal lattice. It matters i set. The large number of exchanged atoms does not significantly alter the crystal structure or lysical properties of the zeolite. For the Seo connector Δ, the average x value no i n is 1.85 and the value falls in the range 1.8b + f, b. Seo] iiti11a X hits the x value in the range 2.5 + 0, b.

The formula for the alloy A can be written as follows: 1.0 + 02 Na-O: AL ,, 0.,: 1.8b. + 0, b d L 0: yiir, 0

The formula for the alloy X can be written as follows: 0.9 + 0.2 Na „0: Al ,, G ,,: 2.5 + 0, b SiO ,: yH ,, 0

The formula of Seo] Iit can be chirped as follows: 1: 0.9 + 0.2 N a0: A1 2 0 3: 4.5 + 1.5 S.in,;: yHo0 where y can be any value up to 6 zeolite A , j ok in value up to 8 seolnt i lia X and some value a.ina \) up to seol iitilla Y.

Aeolite A is fully described in U.S. Patent No. 2,882,243, Zeolite X in U.S. Patent No. H8,224 u, and Zeolite Y in U.S. Patent No. 3,135,007. Their manufacture is also described in k 5-pa rent11s>. dirty in. Other publications on zeolite A include U.S. Patent Nos. 2,98,261 2, 3,058,855, 3,101,251, 3,115 6 5 9, and 40, which describe various methods for zeolite A. to make. Other publications on Sole X include Ud Patent Publications 2,079,381, 3,341,284, 3,602,475, 3,594,121, 3,690,323 and 4 Olb 24b.

It is an object of the present invention to provide zeolites which have a very high exchange capacity for both calcium and magnesium ions and fast consumption rates of calcium ions which are better than similar previously known zeolites.

Another object of the present invention is to provide zeolites having a controlled particle size and useful as ion exchangers in water softening compositions and detergents; as fillers in paper, rubber and plastics and as non-settable dimming pigments.

The zeolite A according to the invention is characterized in that the zeolite germ particles have a narrow differential weight-to-weight Gaussian distribution with an average particle size of at most 2.1 microns and at least 90% by weight of the particles have a size between 1.1 and 4 .0 microns, where in a cumulative percentage population at least 35% of the particles are less than one micron and not more than 5% of the particles are larger than 5 microns, calcium carbonate exchange is greater than 230 mg calcium carbonate per gram of zeolite and magnesium carbonate exchange is greater than 90 mg magnesium zeolite per gram.

For an improved process according to the invention for preparing sodium aluminosilicate zeolite A according to claim 1 by reacting sodium aluminate and sodium silicate by mixing together an aqueous sodium aluminate solution and an aqueous sodium silicate solution and reacting it at a temperature of 40-120 ° C to form an amorphous sodium , which is slightly higher than said stirring temperature to form crystalline sodium aluminosilicate alloys, it is characterized in that aqueous solutions of sodium aluminate and sodium aluminate are mixed into a reaction mixture having the following molar ratios of reaction components: (1) ratio of water to sodium oxide: : 1 (2) ratio of sodium to silica 1: 1 to 2.5: 1 (3) ratio of silica to alumina 3: 1 to 8: 1 and further that when the molar ratio of silica to alumina is 2.0: 1 or below, the maximum reaction temperature is at most 69823 The molar ratios selected for the reaction in the given limits are such that the particle size of the zeolite product increases as the molar ratio of oxide to alumina decreases and decreases as the molar ratio of silica to alumina increases and the particle size of the zeolite product isuht eeseen and directly verranno] lirien a 1 umi in i oks id ikor.sent raat ion; and that the final product is finely divided zeolite A with an average particle diameter of less than 2 microns.

In the reaction mixture of the process of the invention, the molar ratio of water: sodium oxide is between 10: 1 and 35: 1, preferably between 15: 1/0: 1, most preferably about 20: 1, the molar ratio of sodium oxide: silica is between 1: 1-2.5: 1, preferably between 1.2: 1 and 3: 1 and most preferably about 1.5: 1 and the molar ratio of silica: alumina to between 3: 1 and 8: 1, preferably between 2: 1 and 7.3: 1 and most preferably about 7.3: 1. In a separate embodiment, when the molar ratio of sodium to silica is less than ^: 3, the molar ratio of silica to alumina is at least 3: 1. When the molar ratio of sodium oxide to silica is at least 4: 3, the molar ratio of sodium oxide to alumina is at least 4: 1. Furthermore, when the molar ratio of 510: Al 0 ° is 2.0: 1 or less, the maximum

i- / O

The reaction temperature is about 80 C. Even as this ratio decreases, the number of combinations of variables decreases.

The particle size of the alloy A can be controlled by changing the molar ratio of silica to alumina, whereby the particle size decreases as the molar ratio of silica to alumina is increased, and the particle size increases as the molar ratio of silica is reduced. The particle size can also be controlled by changing either the arrow ratio of sodium oxide and alumina or the alumina concentration, whereby the particle size decreases as the molar ratio of sodium oxide and alumina is increased or the alumina concentration is reduced, and the particle size increases as the sodium oxide and alumina alumina and alumina are reduced.

Zeolite A preferably has a calcium carbonate exchange rate greater than 251 mg of calcium carbonate per gram of zeolite and a magnesium exchange capacity of greater than 140 mg of carbonate per gram of zeolite. 90% of its particles are less than 2 microns. The resulting mixture of germ particle particles preferably has a narrow Gaussian weight percentage distribution with an average particle size of up to 1.6 microns and at least 90% by weight of the particles are between 0.1 and 4.0 microns, with at least 64% in the cumulative percentage population being less than one. micron and not more than 1% above 2 micron. It is useful as an ion exchanger in water pointer compositions and detergents, as a filler in paper, rubber and plastics, and as a non-settable dimming pigment.

In one embodiment of the present invention, the zeolite is prepared by dissolving the sand in a sodium hydroxide solution at a pressure of at least 690 kN / m (100 psig), preferably 966 kN / m (140 psig), heated to at least 130 ° C, activating the sodium silicate thus formed with alumina, forming aluminate solution, add the sodium aluminate solution to the sodium silicate solution so that the entire amount of sodium aluminate solution is added within 30 seconds to a reaction mixture comprising sodium silicate mother liquor and amorphous sodium aluminosilicate pigment at a temperature of 80 ° C. 80-120 ° C, then the zeolite produced is recovered. The sodium silicate solution has a molar ratio of silica to sodium oxide of between 2.4: 1 and 2.8: 1, preferably about 2.4: 1. The sodium 11 silicate is activated with 50-2000 ppm alumina at 15-100 ° C for at least 10 minutes, preferably 4U0-600 ppm alumina at room temperature, most preferably about 500 ppm alumina. The sodium silicate solution is heated to a temperature of 80-12 ° C, preferably 90 ° C. The sodium aluminate solution is also heated to a temperature of 80 to 20 ° C, preferably 90 ° C.

The present invention is based on four different considerations: (1) note that the type of zeolite formed is determined by how long it takes to form a zeolite at a given reaction temperature: (2) note that the reaction time required to crystallize a zeolite at a given reaction temperature is primarily a function of water to sodium oxide. and the molar ratio of silica and the molar ratio of silica to alumina have a smaller effect on the reaction time; (3) note that the magnesium exchange capacity of zeolite A is a function of the particle size of the zeolite; and (4) taking into account that the particle size of zeolite i is not a function of the molar ratio of silica to alumina, the molar ratio of sodium to alumina. Icesta ja a lumi inioks id ikon s en ti'aa t i o s ta.

The small and uniform particle size zeolite of this invention is prepared utilizing these four considerations in a high molar ratio of silica to alumina in the reaction mixture, the molar ratios of the other oxides being set to produce the desired zeolite. In known processes for forming zeolites, a sodium-aluminum-silicate-water mixture having a certain composition is prepared. This mixture is kept at a certain temperature until crystals form, then the crystals are separated from the reaction mixture. At molar ratios of silica to alumina of more than two, the reaction mixture consists of sodium silicate mother liquor and amorphous sodium aluminosilicate pigment. When this biphasic reaction mixture is reacted at elevated temperatures, nothing visible occurs over a period of time, but after this period, the zeolite rapidly crystallizes and can then be separated from the reaction mixture.

The present invention is based in part on the fact that the type of zeolite formed with a particular silica source is determined by the reaction time required for crystallization to occur at a particular reaction temperature. When the reaction time is short, hydroxy-soda-lite is formed, but when the reaction time is longer, zeolite A is formed.

When the reaction time is even longer, zeolite X is formed. When the reaction time is between the time required to form zeolite A and the time required to form zeolite X, then a combination of zeolite A and zeolite X is formed. The reaction time depends on the silica source and whether the silica is activated or not. The preferred reaction time for a particular silica source can be readily found by experimentation.

The reaction time required for crystallization at a given reaction temperature can be adjusted in a number of different ways, but the main means of adjusting the reaction time is to set the molar ratio of water to sodium oxide in the reaction mixture. The reaction time required to form the zeolite is directly proportional to the molar ratio of water to sodium used, e.g., when the silica source is not activated with alumina, a molar ratio of water to sodium oxide to prepare zeolite A is between 15: 1 and 20: 1. One possible explanation is that a higher ratio of water to sodium oxide means that the solution is more dilute, which means that it takes more time for the reaction sites to come together, resulting in a longer reaction time. Therefore, in order to obtain zeolite A in the reaction mixture in which the molar ratio of sodium oxide and silica and the molar ratio of silica to alumina are such that zeolite X is normally formed, the molar ratio of water to sodium oxide is reduced. Setting the molar ratio of water to sodium oxide is the main means of controlling the type of zeolite formed and is analogous to flow control in a relative feedback controller.

This relationship between the molar ratio of water and sodium oxide and the type of zeolite formed was not previously known. For example, U.S. Patent Nos. 2,882,243 and 2,882,244 disclose a molar ratio of water to sodium oxide of 35 to 200 for the preparation of zeolite A and a molar ratio of water to sodium oxide of 35 to 60 for the preparation of zeolite X, respectively. If nothing, then this would mean that the reaction mixture for the preparation of zeolite A should have a higher molar ratio of water to sodium oxide than the reaction mixture for the preparation of zeolite X, which is not the case. In U.S. Patent No. 3,119,659, the molar ratio of water to sodium oxide to prepare zeolite A is 20 to 100, while the molar ratio of water to sodium oxide to prepare zeolite X is 30 to 60. None of the aforementioned U.S. patent publications discloses that the molar ratio of water to sodium oxide should be higher for the preparation of zeolite X than for the preparation of zeolite A.

Another way to adjust the reaction time required for crystallization at a given reaction temperature is to adjust the molar ratio of sodium oxide to silica in the reaction mixture. The reaction time required to form the zeolite is inversely proportional to the molar ratio of sodium oxide to silica used. The effect of the molar ratio of sodium oxide to silica is not as strong as the effect of the molar ratio of water to sodium oxide.

8 69823

One possible theory to explain why increasing the molar ratio of sodium oxide to silica reduces the reaction time required to form a sololite is that increasing the molar ratio of sodium oxide to silica by a certain molar ratio of water to sodium oxide lowers the viscosity of the reaction mixture.

Setting the molar ratio of silica to alumina in the reaction mixture also affects the reaction time required for crystallization at a given reaction temperature, but this effect is much less than the effect of the molar ratio of sodium to silica, which in turn is much less than the effect of the molar ratio of water to sodium oxide. A certain molar ratio of water to sodium oxide and a certain molar ratio of sodium oxide to silica have the reaction time required to form the zeolite, directly proportional to the molar ratio of silica to alumina.

The reaction time at a given temperature can be reduced by adding the sodium aluminate solution to the sodium silicate solution at a high rate, preferably so that the entire sodium aluminate solution is added within 30 seconds and more preferably simultaneously. Thus, the reaction time required for crystallization at a given reaction temperature can be increased by increasing the ratio of water to sodium oxide; lowering the molar ratio of sodium oxide to silica; by increasing the molar ratio of silica to alumina and slowly introducing the two substances in question together.

Using these criteria, it has been found that the preferred reaction time to form zeolite A is about 1/2 to 8 hours.

The present invention is also based on the consideration that the magnesium exchange capacity of zeolite A is a function of the size of the zeolite particles. As the particle size decreases, the exchangeability of magnesium increases. With zeolite A, when the average particle diameter is 2.1 microns, the magnesium exchange is only 62 mg / g, when the average diameter is 1.1 microns, the magnesium exchange is about 121 mg / g, and when the average diameter is 0.8 microns, the magnesium exchange is 1S9 mg / g.

Much more important than the effect on the reaction time is the effect of the molar ratio of silica to alumina on the particle size. The reason for this effect is unknown, but the particle size of the zeolite increases as the molar ratio of silica to alumina in the reaction mixture decreases. The particle size decreases as the molar ratio of silica to alumina in the reaction mixture increases. For example, zeolite A has a molar ratio of silica to alumina of 1.85 + 0.5. Therefore, the zeolite A formed in the reaction mixture having a molar ratio of silica to alumina of 10.1 has a smaller particle size than the zeolite A formed in the reaction mixture having a molar ratio of silica to alumina of 2: 1. This means that the particle size of the zeolite can be adjusted by setting the molar ratio of silica to alumina in the reaction mixture. To increase the particle size, the molar ratio of silica to alumina in the reaction mixture would be set to approach the molar ratio of silica to alumina in the desired product. For alloy A, this ratio is 1.85 + 0.5. To reduce the particle size, the molar ratio of silica to alumina in the reaction mixture would be set to differ from the molar ratio of silica to alumina in the desired product.

For zeolite A, the ratio SiC ^ tA ^ O ^ which is? or more, is greater than the molar ratios of silica to alumina in the desired product. Therefore, to increase the particle size of the zeolite A, the molar ratio of silica to alumina in the reaction mixture is reduced. To reduce the particle size, the molar ratio of silica to alumina in the reaction mixture is increased.

Other means of controlling the particle size of the final product include adjusting either the molar ratio of sodium oxide to alumina or the concentration of alumina in the reaction mixture. The particle size is inversely proportional to the molar ratio of sodium oxide to alumina and directly proportional to the alumina concentration. The effects of the molar ratio of sodium oxide to alumina and the concentration of alumina on the particle size are of the same order of magnitude as the effect of the molar ratio of silica to alumina.

Since the molar ratio of silica to alumina, the molar ratio of sodium to alumina and the alumina concentration are all interdependent, it is currently unclear what is the predominant factor, but any of the three variables mentioned, or a combination of these, can be used to adjust the particle size.

The molar ratio of sodium oxide to silica in the reaction mixture also affects the particle size of the final product, but this effect is much smaller than the effect of the molar ratio of silica to alumina. At a constant mcoli ratio of silica to alumina, the particle size is inversely relative to sodium oxide. and the molar ratio of silica. As the molar ratio of sodium oxide to silica increases, the particle size decreases. As the molar ratio of sodium oxide to silica decreases, the particle size increases. Thus, the effect of the molar ratio of sodium to silica in the reaction mixture on the particle size can be used in conjunction with the effect of the molar ratio of silica to alumina as a means of adjusting the particle size.

The molar ratio of water to sodium oxide in the reaction mixture also affects the particle size of the final product, but this effect is of a smaller order of magnitude than the effect of the molar ratio of sodium oxide to silica. The reaction temperature also affects the particle size.

Although batch composition and reaction temperature are used to control particle size, there are conditions under which precipitation can occur. As a result of impact fusing, a product does not have the expected properties of the expected particle size. The processes described in the working examples are directed to optimal conditions in which no precipitation occurs. If the temperature of the reactants at the time of mixing is too low or the concentration of sodium oxide or water in the solutions used is greatly altered, precipitation can be expected. In the extreme case, a two-Eodal division may occur. These effects can be avoided by techniques such as longer mixing times, reverse order of addition, higher mixing rates, etc. It is important to note that these techniques do not really control the primary particle size, they only change the amount of seeding. Only the batch composition and reaction temperature control the primary particle size and the type of product formed.

According to the present invention, zeolites having a small and uniform particle size and good magnesium exchange capacity are produced by forming a sodium aluminate solution, forming 11,692,83 sodium silicate solution and mixing the sodium aluminate solution and sodium silicate solution to form a reaction mixture. At molar ratios of SiO 2 Al 2 O 2 greater than 2, this mixture comprises sodium silicate broth and amorphous sodium aluminosilicate pigment. In said ratios of 2 and less than 2, the mixture contains sodium lumininate. The reaction mixture is heated and reacted at 40-120 ° C, preferably 60-100 ° C, until the desired zeolite is formed from the mother liquor. In a preferred method, the sodium aluminate and sodium silicate solution is preheated to 50-120 ° C, preferably 60-100 ° C before mixing. After stirring, an exothermic reaction takes place which raises the temperature to about 10 ° C, at which temperature the reaction takes place. The zeolite is then recovered from the reaction mixture by conventional solids separation techniques such as filtration. The mother liquor or filtrate can be recycled to utilize dissolved sodium and silicon or sodium and aluminum.

In the process of the invention, the sodium silicate solution can be formed by dissolving sand in sodium hydroxide solution at a pressure of at least 690 kN / m 2 and at a temperature of at least 130 ° C to produce a sodium silicate solution having a molar ratio of silica to sodium oxide of 2.4: 1-2.8: 1. The word "sand" here has its usual meaning "bulk material consisting of small but easily separable grains, usually less than two millimeters in diameter, most commonly quartz, derived from the breakdown of stones and commonly used to make glass and mortar, as an abrasive or molding agent in casting". A temperature of at least 130 ° C is used to dissolve the sand (sanna) because it is more difficult to dissolve the sand at lower temperatures.

This sodium silicate solution is preferably activated with 50-2000 ppm alumina and heated to 40-120 ° C for at least 10 minutes, the activation being preferably performed with 400-600 ppm alumina at room temperature. Alumina concentrations below 50 ppm do not activate silica. Alumina concentrations above 2000 ppm cause alumina to precipitate from solution as amorphous sodium aluminosilicate. Preferably, the molar ratio of silica to sodium oxide in the sodium silicate solution is about 2.4: 1-2.8: 1, because this sodium silicate solution is usually cheaper to prepare than solutions with a higher molar ratio of silica to sodium oxide, such as in water glass.

After the sodium silicate solution is formed and is either activated or not activated, the sodium aluminate solution is added to the sodium silicate solution by addition to form a reaction mixture.

When the sodium silicate source is activated with alumina, the preferred reaction mixture to form the zeolite A has a molar ratio of water to sodium oxide of 25: 1-35: 1, a molar ratio of sodium oxide to silica of 1.4: 1-2: 1 and a molar ratio of silica to alumina of 3: 1. -7: 1. When the sodium silicate source is not activated with alumina, the preferred reaction mixture has a molar ratio of water to sodium oxide of between 15: 1 and 20: 1, a molar ratio of sodium oxide to silica of between 1.5: 1-2: 1 and a molar ratio of silica to alumina of between 2 : 1 to 5: 1.

The broad molar ratio ranges of oxides for the preparation of the zeolite are shown in Table I.

Table I

Wide areas for making zeolites Zeolite Water / Sodium oxide / Silica / ____ sodium oxide silica alumina A 10-35 1-4 1-10

Preferred molar ratio ranges of oxides for the preparation of the zeolite using a source of sodium silicate not activated with alumina are shown in Table II.

Table II

Preferred areas for the preparation of zeolites (not activated)

Zeolite Water / Sodium oxide / Silica / _ sodium oxide silica alumina A 15-20 1,4-2 2-4 13 69823

Preferred molar ratio ranges of oxides for the preparation of the zeolite using a source of sodium silicate activated with alumina are shown in Table III.

The table lii

Preferred regions for the preparation of zeolites C activated)

Zeolite Water / Sodium oxide / Silica / _ sodium oxide silica alumina A 25-35 1,4-2 3-7

To ensure a good yield of the desired zeolite product, it is necessary to react the zeolite mixture beyond a certain time minimum. However, if the reaction is continued for too long, the product will start to lose silica, that is, the ratio of silica to alumina will begin to decrease, and if the reaction is still continued, then the product may be recrystallized to a non-fed zeolite. There is an optimal reaction time, which is determined in part by the ratios and concentrations of the initial reaction mixture, the size of the batch, the time required to mix the ingredients and the amount of heating. The optimum reaction time at certain molar ratios can be easily determined experimentally. However, in general, the reaction time for preparing the zeolite A is in the range of 0.5 to 8 hours.

After the zeolite has been separated from the mother liquor, the latter can be recycled. Recirculating the mother liquor eliminates the dilemma where the mother liquor is placed. While it is possible to use the process of the present invention without recycling base 1, failure to recycle the mother liquor may make the process unprofitable.

The molar ratio of silica to alumina in zeolite A is about 1.85: 1. As already mentioned above, the particle size of the zeolite is smaller when the molar ratio of silica to alumina in the reaction mixture is higher in the desired zeolite, with molar ratios of silica to alumina greater than 2. As a result, the zeolite A of the present invention has a smaller particle size than before.

1U 69823

Due to its small particle size, the zeolite A of the present invention is useful in a variety of applications, such as as an ion exchanger in water softening compositions and detergents, as a filler in paper, rubber and plastics, and as a non-settable dimming pigment.

Zeolite A, which has a smaller particle size, has a higher magnesium ion exchange capacity than the previously known zeolite A, which has a larger particle size. The increased exchange capacity of magnesium ions makes this zeolite A particularly useful as an ion exchanger in water softeners and detergents.

Another factor that makes zeolites particularly useful as ion exchangers is their rapid rate of removal of calcium carbonate. These zeolites remove calcium ions faster than zeolites with a larger particle size. Zeolite A, which has a smaller particle size, exchanges calcium ions at a higher rate than zeolite A, which has a larger particle size.

Any source of sodium silicate can be used in the present invention, but a particularly preferred source of sodium silicate is sand dissolved in sodium hydroxide. The advantage of this source is its cheapness. The sand is dissolved in sodium hydroxide solution at a pressure of at least 690 kN / m 2 and at a temperature of at least 130 ° C to produce a sodium silicate solution in which the molar ratio of silica to sodium oxide is between 2.4: 1-2.8: 1. The preferred pressure is about 966 kN / m, which produces a sodium silicate solution with a molar ratio of silica to sodium oxide of about 2.4: 1.

The time required to produce a particular product from batches of identical chemical composition depends on the silica source. Each type of silica source has its own schedule that determines the reaction times required to prepare each type of zeolite. One of the considerations on which this invention is based is the fact that this schedule can be altered by activating the silica source with alumina, as described above. The alumina concentration limits of 50 ppm to 2000 ppm are critical values because alumina concentrations below 50 ppm fail to activate the sodium silicate solution.

is 69823

The alumina used to activate the sodium silicate solution may suitably be in the form of a soluble aluminum compound such as sodium aluminate or a water-soluble aluminum salt such as aluminum sulphate. However, sodium aluminate is a preferred reagent because it limits the tendency for foreign ions to enter the zeolite crystal lattice.

There is an important difference between the activation effect and the effect of reaction time adjusting factors, which are influenced by factors such as the molar ratio of water to sodium oxide, the molar ratio of sodium to silica, the molar ratio of silica to alumina and the rate of addition (stirring rate). Reaction time control factors are used to set the reaction time required for crystallization to match the reaction time given in the schedule to produce a particular zeolite. Activation changes the schedule. Therefore, the preferred oxide molar ratios for preparing the desired sololite are different when the silica source is either activated or not activated.

eXAMPLES

The invention is further illustrated by the following examples, which show a particularly preferred method and embodiments of the composition.

In the examples and throughout the specification, amounts are by weight unless otherwise indicated.

The following examples were carried out as described above by forming silicate and aluminate solutions, preheating each solution to the indicated temperature and adding the aluminate solution to the silicate solution within the indicated time. The resulting gel was broken by stirring until a homogeneous slurry was obtained and the batch was reacted at the indicated temperature for a reaction time. The resulting product was characterized by its calcium ion exchange capacity expressed in mg of calcium carbonate per gram of zeolite and its magnesium ion exchange capacity expressed in mg of magnesium carbonate per gram of zeolite. The resulting zeolite particles have been characterized as different weight percentages in a Gaussian distribution, with an average particle size in microns of 16,692,823 and a weight between 0.1 and 2.5 microns. The cumulative percentage population is also described. These criteria are presented in the following tables.

In the examples, the exchange capacity of calcium carbonate was determined by placing the zeolite in the exchange solution, stirring for fifteen minutes, filtering off the zeolite and titrating the filtrate with EDTA solution (ethylenediaminetetraacetic acid solution) to determine how much calcium ions had been removed. The exchange solution was made from calcium chloride to give a concentration equivalent to a solution of 122 g of calcium carbonate per liter. The filtrate was buffered to pH 10, then Erichrome Black T indicator (3-hydroxy-k - ((1-hydroxy-2-naphthyl) azo) -7-nitrol-naphthalenesulfonic acid sodium salt) was added to the filtrate before EDTA titration.

The exchangeability of magnesium carbonate was determined by placing the zeolite in the exchange solution, stirring for fifteen minutes, filtering off the zeolite and titrating the filtrate with EDTA solution to determine how much magnesium ions had been removed. The exchange solution was made from magnesium chloride to give a concentration equivalent to a solution of 1000 ppm magnesium carbonate. The filtrate was buffered to pH 10, then Erichrome Black T indicator was added to the filtrate before EDTA titration.

Particle size measurements were performed with a Coulter Counter (Model TAII). Particle Size Analysis Coulter Counterilia measures both sample volume and the number of particles in specific size ranges. Since volume percentage and weight% are synonymous when all particles have the same density, weight% is used because it is the most common way to express particle size data.

The following terms are used to describe particle size in the context of the present invention.

Gaussian (Gaussian) Distribution: Frequency curves of the Gaussian distribution, also known as symmetric or clock-shaped frequency curves, are characterized by the fact that the observations of the same distant maximum have the same frequency (frequency of occurrence).

Average particle size: The average particle size is the size at which 50% of the total weight is calculated. The results were confirmed by scanning electron microscopy.

Cumulative% (percentage) population: The cumulative% population is the percentage of all calculated particles.

The following are examples of the preparation of zeolite A and the characteristic properties of the product. In these examples, the exchange values apply to zeolite anhydrous.

18 „,, _w 6 9 8 2 3

Table IV

Composition of the reaction mixture for the preparation of zeolite A v · / Silicon ^% k ‘% Sodium% Silicon% Aluminum

Water / oxide / sidi / alu-% ntau ·,. <E · · 1Γ · sodium silicon oxy

Example oxide sidi sidi water aia dia 1 30 3.0 2.5 95.34 3> 18 1.06 0.42 2 25 2.4 3.0 94.14. 3.77 1.57 0.52 3 25 2.4 3.0 94.14 3.77 3.57 0.52 4 25 2.4 2.5 94.04 3.75 3.57 o.63 5 25 2.4 2.0 93.90 3.75 1.57 0.78 6 25 2.4 2.0 93.90 3.75 3.57 0.78 7 25 2.0 2.5 93.63 3.75 3.37 0.75 8 25 2.0 2.0 93.46 3.74 3.37 0.93 9 25 2.0 2.0 93.46 3.74 3.37 q.93 10 20 3.0 2.5 93.17 4.66 1.55 0.62 11 20 3.0 2.5 93.17 4.66 1.55 0.62 12 20 3.0 2.5 93.17 4.55 3.55 o.62 13 20 2.8 2.5 93.02 4.65 3.66 0.66 14 20 2.8. 2.5 93.02 4.55 3.66 0.66 15 20 2.8 2.5 93.02 4.65 1.66 0.66 16 20 2.6 2.5 92.86 4. (34 3.79 0.71 17 20 2.6 2.5 92.86 4.54 3.79 0.71 18 20 2.6 2.5 92.86 4.54 1.79 0.71 19 20 2.2 5.3 92.85 4.54 2.11 0.40 20 25 1.6 2.0 92.81 3.73 2.32 1.16 21 20 2.4 3.0 92.78 4.54 3.93 q.65 22 20 2.4 3.0 92.78 4.54 3.93 o.65 23 20 2.2 4.3 92.76 4.54 2.11 0.49 24 20 2.0 7.3 92.73 4.54 2.32 0.32 25 20 2.0 7.3 92.73 4.54 2.32 0.32 26 20 2.0 6.3 92.68 4.63 2.32 0.37 27 20 2.4 2.5 92.66 4.53 3.93 q.77 28 20 2.4 2.5 92.66 4.53 3.93 o.77 29 20 2.4 2.5 92.66 4.53 3.93 0.77 30 20 2.4 2.5 92.66 4.53 3.93 q.77 31 20 2.0 5 .3 92.62 4.53 2.32 0.44 32 20 1.9 7.3 92.60 4.63 2.44 0.33 33 20 2.0 4.3 92.52 4.53 2.31 0.54 34 20 2.4 2.0 92.49 4.53 1.93 0.96 35 20 2.4 2.0 92.49 4.52 1.93 0.96 36 20 1.8 7.3 92.46 4.62 2.57 0.35 37 20 2.2 2.5 92.44 4.62 2.10 0.84 38 20 2.2 2.5 92.44 4.52 2.10 0.84 39 20 2.2 2.5 92.44 4.53 2.10 0.84 40 20 1.8 6.3 92.41 4.53 2.57 0.41 41 20 .2.0 3.3 92.37 4.52 2.31 0.70 42 20 2.0 3.3 92.37 4.53 2.31 0.70 43 20 1.7 7.3 92.30 4. ¢ 2 2.72 0.37 44 20 1.8 4.3 92.23 4.61 2.56 0.60 45 20 2.0 2.5 92.17 4.61 2.30 0.92 46 20 2.0 2.5 92.17 4.61 2.30 0.92 i9 698 2 3 47 20 2.0 2.5 92.17 4.61 2.30 0.92 48 20 2.0 2.5 92.17; 4.61 2.30 0.92 49 20 1.6 7.3 92.12 4.61 2.88 0.39 50 20 1.6 7.3 92.12 4.61 2.88 0.39 51 20 1.6 7.3 92.12 4.61 2.88 0.39 52 20 1.6 7.3 92.12 4.61 2.88 0.39 53 20 1.6 7.3 92.12 4.61 2.88 0.39 54 20 1.8 3.3 92.06 4.60 2.56 0.77 55 20 1.6 5.3 91.98 4.60 2.87 0.54 56 20 2.0 2.0 91.95 4.60 2.30 1.15 57 20 2.0 2.0 91.95 4.60 2.30 1.15 58 20 1.5 7.3 91.92 4.60 3.06 0.42 59 20 1.5 7.3 91.92 4.60 3.06 0.42 60 20 1.5 6.3 91.86 4.59 3.06 0.49 61 20 1.5 6.3 91.86 4.59 3.06 0.49 62 20 1.8 2.5 91.84 4.59 2.55 1.02 63 20 1.8 2.5 91.84 4.59 2.55 1.02 64 20 1.8 2.5 91.84 4.59 2.55 1.02 65 20 1.5 5.3 91.77 4.59 3.06 0.58 66 20 1.4 7.3 91.69 4.59 3.28 0.45 67 20 1.6 3.3 91.68 4.58 2.87 0.87 68 20 1.6 3.3 91.68 4.58 2.87 0.07 69 20 1.6 3.3 91.68 4.58 2.87 0.87 70 20 1.6 3.3 91.68 4.58 2.87 0.87 71 20 1.6 3.3 91.68 4.58 2.87 0.87 72 20 1.4 6.3. 91.63 4.58 3.27 0.52 73 20 1.6 3.0 91.60 4.58 2.86 0.96 74 20 1.4 5.3 91.54 4.58 3.27 0.62 75 20 1.6 2.5 91.43 4.57 2.86 1.14 76 20 1.6 2.5 91.43 4.57 2.86 1.14 77 20 1.4 3.3 91.20 4.56 3.26 0.99 78 20 1.6 2.0 91.17 4.56 2.85 1.42 79 20 1.6 2.0 91.17 4.56 2.85 1.42 80 20 1.2 7.3 91.13 5.56 3.80 0.52 81 20 1.2 6.3 91.05 4.55 3.79 0.60 82 20 1.4 2.5 90.91 4.55 3.25 1.30 83 20 1.4 2.5 90.91 4.55 3.25 1.30 84 20 1.2 4.3 90.80 4.54 3.78 0.88 85 20 1.2 3.3 90.56 4.53 3.77 1.14 86 15 2.4 2.5 90.45 6.03 2.51 1.01 87 15 2.4 2.0 90.23 6.02 2.51 1.25 88 20 1.2 2.5 90.23 4.51 3.76 1.50 89 15 2.0 2.0 89.55 5.97 2.99 1.49 90 15 1.6 2.5 88.89 5.93 3.70 1.48 91 15 1.6 2.0 88.56 5.90 3.69 1.85 92 15 1.6 2.0 88.56 5.90 3.69 1.85 2 0 69823

Table V

Zeolite A - reaction conditions Thermal o _ ...... Reaction. . Silicon Aluminum Addition Temperature Reaction

Example xate naate time (sec) la _time (h).

1 90 90 30 100 4.0 2 50 50 30 60 8.0 3 70 70 30 80 2.0 4 50 50 30 60 7.5 5 50 50 30 60 6.0 6 70 70 30 80 2.5 7 50 50 30 60 6.5 8 50 50 30 60 6.5 9 70 70 30 80 2.5 10 50 50 30 60 4.0 11 70 70 30 80 1.5 12 90 90 30 100 0.5 13 50 50 30 60 4.0 14 70 70 30 80 2.0 15 90 90 30 100 0.5 16 50 50 30 60 3.0 17 70 70 30 80 2.0 18 90 90 30 JOO 0.5 19 90 90 30 100 0.5 20 50 50 30 60 8.0 21 50 50 30 60 3.5 22 70 70 30 80 2.0 23 90 90 30 100 1.0 24 90 90 30 100 2.0 25 90 90 30 JOO 1.0 26 90 90 30 100 1.0 27 50 50 30 60 4.0 28 70 70 30 80 1.5 29 90 90 30 100 2.5 30 90 90 30 100 0.5 31 90 90 30 100 1.0 32 90 90 30 100 1.0 33 90 90 30. 100 1.0 34 50 50 30 60 3.5 35 70 70 30 80 1.0 36 90 90 30 100 1.0 37 70 70 30 80 1.5 38 50 50 30 60 4.0 39 90 90 30 100 0.5 40 90 90 30 100 2.0 41 90 90 30 100 2.0 42 90 90 600 100 2.0 43 90 90 30 100 1.0 44 90 90 30 100 2.0 45 50 50 30 60 4.0 46 70 70 30 80 3.0 21 69823 47 50 50 30 60 3.5 48 90 90 30 100 0.5 49 90 90 30 100 2.0 50 90 90 300 100 1.5 51 90 90 600 100 2.0 52 90 90 1200 100 2.0 53 90 90 30 100 2.0 54 90 90 30 100 1.0 55 90 90 30 100 2.0 56 50 50 30 60 4.5 57 70 70 30 80 1.5 58 90 90 30 100 2.0 59 90 90 30 100 2.0 60 90 90 30 100 8.0 61 90 90 30 100 2.0 62 70 70 30 80 1.5 63 50 50 30 60 4.0 64 90 90 30 100 0.5 65 90 90 30 100 2.0 66 90 90 30 100 4.0 67 90 90 30 100 1.5 68 90 90 30 100 1.5 69 90 90 300 100 1.5 70 90 90 600 100 1.5 71 90 90 1200 100 1.5 72 90 90 30 100 3.0 73 70 70 30 80 3.0 74 90 90 30 100 3.0 75 70 70 30 80 3.0 76 90 90 30 100 1.0 77 90 90 30 100 1.0 78 50 50 30 60 4.0 78 70 50 30 60 4.0 79 70 70 30 80 2.3 80 90 90 30 100 3.0 81 90 90 30 100 3.0 82 70 70 30 80 3.0 83 90 90 3 0 100 2.0 84 90 90 30 100 2.0 85 90 90 30 100 2.0 86 50 .50 30 60 3.5 87 50 50 30 60 3.5 88 70 70 30 80 3.0 89 50 50 30 60 2.0 90 70 70 30 80 1.0 91 50 50 30 60 3.5 92 70 70 30 80 1.0 69823 22

Table VI Zeolite Exchange capacity .. Sodium- Medium- Calcium- Magnesium-. oxide /% Primary exchange

LSmark S ^ .a lu_ aluminum-aluminum diameter ability

the so-called sign oxide oxide position ___1_ 'Y

1 2.5 7.5 0.42 2.4 292 62 2 3.0 7.2 0.52 0.9 300 1J4 3 3.0 7.2 0.52 1.25 274 136 4 2.5 6.0 0.63 0.86 283 145 5 2.0 4.8 0.78 1.4 300 141 6 2.0 4.8 0.78 2.1 273 124 7 2.5 5.0 0.75 1.1 322 133 8 2.0 4.0 0.93 1.5 304 136 9 2.0 4.0 0.93 2.4 278 105 10 2.5 7.5 0.62 0.90 295 162 11 2.5 7.5 0.62 1.3 293 163 12 2.5 7.5 0.62 1.4 295 107 13 2.5 7.0 0.66 0.93 291 158 14 2.5 7.0 0.66 1.2 293 156 15 2.5 7.0 0.66 1.5 287 117 16 2.5 6.5 o.71 0.90 288 154 17 2.5 6.5 o.71 1.4 300 154 18 2.5 6.5 0.71 1.5 278 118 19 5.3 11.7 o.40 0.7 270 163 20 2.0 3.2 i.i6 2.0 283 127 21 3.0 7.2 0.65 1.1 280 137 22 3.0 7.2 0.65 0.83 335 131 23 4.3 9.5 0.49 0.84 249 159 24 7.3 14.6 0.32 0.95 273 148 25 7.3 14.6 0.32 1.0 262 147 26 6.3 12.6 0.37 0.7 252 147 27 2.5 6.0 0.77 0.80 282 153 28 2.5 6.0. 0.77 1.3 295 150 29 2.5 6.0 0.77 1.0 299 145 30 2.5 6.0 0.77 1.5 284 123 31 5.3 10.6 0.44 0.75 249 145 32 7.3 13.9 0.33 0.86 260 149 33 4.3 8.6 0.54 0.93 290 142 34 2.0 4.8 0.96 1.1 327 155 35 2.0 4.8 0.96 1.7 293 125 36 7.3 13.1 0.35 0.88 261 146 37 2.5 5.5 0.84 1.4 289 152 3 8 2.5 5.5 () .84 0.85 2 8 5 149 39 2.5 5.5 Q.84 1.7 300 109 40 6.3 11-3 p.41 0.95 297 123 41 3.3 6.6 p.70 0.94 292 136 42 3.3 6.6 o.70 1.1 251 126 43 7.3 12.4 0.37 0.80 264 147 44 4.3 7.7 o.60 1.90 286 99 45 2.5 5.0 0.92 1.1 281 157 46 2.5 5.0 0.92 1.3 290 149 2 3 69823 47 2. 5 5.0 0.92 0.07 296 134 48 2.5 5.0 0.92 1.7 283 124 49 7.3 11.7 0.39 1.0 255 135 50 7.3 11.7 0.39 1.0 245 144 51 7.3 11.7 0.39 0.90 259 149 52 7.3 11.7 0.39 0.84 257 151 53 7.3 11.7 0.39 1.1 272 144 54 3.3 5.9 0.77 1.1 290 103 55 5.3 8.5 0.54 0.92 255 150 56 2.0 4.0 1.15 1.3 297 140 57 2.0 4.0 1.15 2.0 293 115 58 7.3 11.0 0.42 0.9 256 145 59 7.3 11.0 0.42 1.1 249 127 60 6.3 9.5 0.49 0.95 273 127 61 6.3 9.5 0.49 1.1 234 123 62 2.5 4.5 1.02 1.2 287 157 63 2.5 4.5 1.02 1.0 281 149 64 2.5 4.5 1.02 1.7 281 113 65 5.3 8.0 0.58 1.1 250 118 66 7.3 10.2 0.45 1.5 254 143 67 3.3 5.3 0.87 1.2 265 145 68 3.3 5.3 0.87 1.5 248 136 69 3.3 5.3 0.87 1.4 264 128 70 3.3 5.3 0.87 1.4 254 127 71 3.3 5.3 '0.87 1.7 239 92 72 6.3 8.8 0.52 1.6 307 145 73 3.0 4.8 0.96 1.95 292 135 74 5.3 7.4 0.62 1.4 278 148 75 2.5 4.0 1.14 1.2 288 160 76 2.5 4.0 1.14 2.0 278 86 77 3.3 4.6 0.99 1.3 272 121 78 2.0 3.2 1.42 1.2 311 118 79 2.0 3.2 1.42 2.2 300 119 80 7.3 8.8 0.52 1.6 241 144 81 6.3 7.6 0.60 1.4 300 144 82 2.5 3.5 1.30 1.3 286 145 83 2.5 3.5 1.30 1.9 288 112 84 4.3 5.2 0.88 1.2 290 148 85 3.3 4.0 1.14 1.6 274 153 86 2.5 6.0 1.01 0.92 315 157 87 2.0 4.8 1.25 1.4 289 140 88 2.5 3.0 1.50 1.6 273 134 89 2.0 4.0 1.49 0.97 275 145 90 2.5 4.0 1.48 1.2 274 129 91 1.6 3.2 1.85 1.4 312 143 92 1.6 3.2 1.85 1.0 279 155 69823 24

Linear regression analysis was performed on the values reported above and correlation coefficients (r) were calculated for certain variables. This analysis showed a clear correlation between magnesium exchange capacity and mean particle size (r = −0.581). Based on this sample, there is less than a 1% probability that no correlation exists between the two variables. There is a less than 1% probability that there is no correlation between the molar ratio of silica to alumina and the average particle size (r = -0.405); between the molar ratio of sodium oxide to alumina and the average particle size (r = -0.469); and between the alumina concentration and the average particle size (r = +0.465). Thus, the average particle size and magnesium solubility can be controlled by setting either the molar ratio of silica to alumina or the molar ratio of sodium to alumina or the alumina concentration.

Table VII 69 8 2 3 25

Zeolite A - particle properties Average. Particle size Kumula particle range min. dense%

Esi ~. size mik- 90% by weight less than one character - pony_micron _ * _ micron in- - 1 2.4 1.0-4.0 19 Max 5%> 3.2u 2 0-9 0.1-2.0 96 Max 5%> 1.25 1 '

3 1.2 5 0.1-2.5 6 7 Max 1%> 2. OM

4 0.86 0.1-1.6 92 Max 1¾> 2.0U

5 1.4 0.1-2.5 58 Max 2%> 2.5 u 6 2.1 0.1-4.0 3 5 Max 5%> 2.5 8 7 1.1 0.1-2.5 86 Max 1¾> 1.6 8

8 1.5 0.1-2.5 5 8 Max 1¾> 2.5 M

9 2.4 0.1-5.0 61 Max 1%> 3.28 10 0.9 0.1-2.0 92 Max 1%> 1.6u

H 1.3 0.1-3.2 68 Max 1%> 2.0U

12 1. 4 0.1-2.5 56 Max 1%> 2.5 0 13 0.93 0.1-2.5 92 Max 1%> 1.68 14 1.2 0.1-2.5 73 Max 1%> 2.01 '15 1.5 0.1-3.2 55 Max 1%> 2.58 16 0.9 0.1-2.5 93 Max 1¾> 1.6u 17 1.4 0.1-3.2 64 Max 1%> 2.0 8 18 1.5 0.1-3.2 53 Max 1¾> 2.58 19 ° · 7 0.1-1.6 98 Max 1%> 1.38 20 2.0 0.1-4.0 39 Max 1% > 3.28 21 1-1 0.1-2.5 97 Max 1%> 1.68 22 0.8 0.1-1.6 95 Max 1%> 1.68 2 3 0.84 0.1-2.0 94 Max 1%> 1.311 24 0-95 0.1-2.0 96 Max]%> 1.38 25 1.0 0.1-2.0 96 Max 1%> 1.38 26 O · 7 0.1-2.0 98 Max 1¾> 1.38 27 0.8 0.1-2.0 96 Max 1%> 1.258 28 l.-l 0.1-2.5 71 Max 1%> 2.0 8 29 1.0 0.1-2.5 88 Max 1%> 1.68 30 1-5 0.1-3.2 55 Max 1%> 2.58 31 0.75 0.1-2.0 97 Max 1%> 1.38 32 0-86 0.1-2.0 96 Max 1%> 1.38 33 0.93 0.1-2.0 97 Max 1%> 1.258 34 1.1 0.1-2.0 83 Max 1¾> 2.08 35 l · 7 0.1-4.0 46 Max 1%> 2.5u 36 0.88 0.1-2.0 96 Max 1%> 1.3u 37 1.4 0.1-3.2 73 Max 1%> 2.0u 38 0 * 85 0.1-2.5 94 Max 1%> 1.68 39 l · 7 0.1-4.0 50 Max 1%> 2.58 40 0.95 0.1-2.0 97 Max 1¾> 1.38 41 0.94 0.1-2.0 94 Max 1%> 1.68 42 1.1 0.1-2.0 82 Max 1%> 1.68 43 0.8 0.1-2.0 96 Max 17> 1.38 44 0.9 0.1-2.0 97 Max 1%> 1.68 4 5 1.1 0.1-3. 2 94 Max .17> 1.68 46 1.3 0.1-3.2 77 Max 1%> 2.08 26 6982 3 47 0.87 0.1 -2.0 96 Max 1%> 1.3 μ 48 1.7 0.1-4.0 54 Max 1%> 2.5u 4 9 1.0 0. 1-2.0 86 Max 1¾> 1.6 π 50 1.0 0.1-1.6 80 Max 1¾> 1.6u 51 0.9 0.1-1.6 90 Max 1%> 1.6u 52 0.84 0.1 -1.6 95 Max 1%> 1.6 μ 53 1.1 0.1-2.0 97 Max 1¾> 1.6u 54 1.1 0.1-2.5 86 Max 1%> 2.On

55 0.92 0.1-2.0 95 Max 1%> 1.6U

56 1.3 0.1-3.2 71 Max 1¾> 2.0 μ

57 2.0 0.1-5.0 40 Max 1%> 3.2U

58 0.9 0.1-2.0 96 Max 1%> 1.6U

59 1.1 0.1-2.0 96 Max 1%> 1.6 μ 60 0.95 0.1-2.5 95 Max 1¾> 1.6u 61 1.1 0.1-2.0 95 Max 1¾> 1.6 μ 62 1.2 0.1-3.2 80 Max 1¾> 2.0 μ 63 1.0 0.1-2.5 92 Max 1%> 1.60

64 1.7 0.1-4.0 56 Max 1¾> 2.5M

65 1.1 0.1 -2.0 95 Max 1%> 1.61 '

66 0.9 0.1-2.0 97 Max 1 ?,> 1.6H

67 1.2 0.1-2.0 85 Max 1%> 1.60 68 1.5 0.1-3.2 53 Max 1%> 2.5u 69 1.4 0.1 -3.2 51 Max 5%> 2.0 μ 70 1.4 0.1-3.2 54 Max 4%> 2.0u 71 1.7 0 . 1-4.0 6 2 Max 2%> 2.5 μ 72 1.1 0.1-3.2 91 Max 1%> 2.0 μ

73 0.95 0.1-2.0 95 Max 1%> 1.6U

7 4 1.4 0.1 -3.2 95 Max 1%> 1.6 μ 75 1.2 0.1-3.2 80 Max 1%> 2.0 μ 76 2.0 0.1-5.0 48 Max 1%> 3.2u 7 7 1.3 0.1-3.2 7 6 Max 1¾> 2.0 μ 78 1.2 0.1-3.2 76 Max 1¾> 3.2u 79 2.2 0.1-5.0 34 Max 1%> 3.2 μ 80 1.6 0.1-4.0 80 Max 5%> 1.6.μ

81 1.4 0.1-4.0 95 Max 1%> 2.0U

82 1.3 0.1-3.2 79 Max 1%> 2.0μ 83 1.0 0.1-5.0 57 Max 1%> 3.2t 84 1.2 0.1 -3.2 86 Max IS> 2.0 μ 8 5 1.6 0.1 -4.0 80 Max 1¾> 2.0 μ

86 0.92 0.1-2.0 98 Max 1¾> 1.25U

87 1.4 0.1-3.2 77 Max 1¾> 2.On 88 1.6 0.1-4.0 71 Max 1%> 2.50

89 1-92 0.1-2.5 91 Max 1¾> 1.6W

90 1.2 0.1 -3.2 95 Max IS> 1.6 U

91 1.4 0.1-3.2 67 Max 1%> 2.5U

92 1.8 0.1-4.0 53 Max 1%> 2.5U

The following examples for the preparation of low particle size zeolite A were performed to illustrate the use of SiO 2: Al 2 O 3 molar ratios in the range of 1: 1 to 1.5: 1.

Table VIII

27 69823

Composition of the reaction mixture for the preparation of zeolite A _ES-j_ Water / Sodium-Silica-Silicate-Silicate-Aluminate-Aluminate-mark sodium oxide / oxide /. tiliuos, kata-, tiliuos. solution oxide silica- Aluminum% Na ~ 0 solution% Na „0% A1„ 0 silicon oxide% SiO ^ ^ ^ 93 15 1.6 1.5 10.6 25.8 17.4 15.9 94 25 1.6 1.5 5.5 13.4 14.9 13.6 '95 15 2.4 1.5 8.3 20.2 19.8 10.8 96 25 2.4 1.5 3.3 8.2 19.8 10.8 97 20 2.4 1.0 6.2 15.3 15.9 13.0 98 20 2.0 1.0 8.5 20.8 13.9 14.2 99 25 2.4 1.0 4.0 9.8 15.9 13.0 100 25 2.0 1.0 5.2 12.8 13.9 14.2.

Table IX Reaction conditions - zeolite A

Preheating. Temperature ° C Addition Reaction Reaction Symbol Silicate Aluminate time, s temperature time, h _ ^ __ 93 70 70 30 80 1.5 94 50 50 30 60 6.0 95 50 50 30 60 3.5 96 50 50 30 60 4.0 97 50 50 30 60 5.0 98 50 50 30 60 6.5 99 50 50 30 60 5.0 100 50 50 30 60 7.0

Table X

Particulate properties - zeolite A

Pre- Average. Particle Size- Cumulative Change sign particle size range min. % less than one micron 90% by weight, micron __micron____ 93 2.2 0.1-5.0 58 Max 1%> 3.2 μ 94 1.8 0.1-4.0 33 Max 1%> 3.2 μ 1 95 1.7 0.1-4.0 44 Max 1%> 2.5 g 96 1.5 0.1-2.5 56 Max 1¾> 2.5 u 97 1.2 0.1-2.5 74 Max 1%> 2.0 μ 98 1.3 0.1-3.2 73 Max 1%> 2.0μ 99 1.1 0.1-2.5 82 Max 1%> 2.0 μ 100 1.4 0.1- 3.2 69 Max 1%> 2.0μ 69823 28

Table XI

Zeolite A interchangeability

Pre- Average. Calcium- Magnesium exchange mark diameter ^ u exchange capacity ability 93 2.2 298 93 94 1.8 296 111 93 1.7 294 100 96 1.5 311 134 97 1.2 291 93 98 1.3 270 96 99 l.i 289 121 100 1.4 270 114 29 69823

As can be seen from Examples 1-92, the following are the preferred molar ratios for preparing zeolite A at reaction temperatures of 60-100 ° C:

Water / sodium oxide 15.0 - 30.0

Sodium oxide / silica 1.2 - 3.0

Silica / alumina 2.0 - 7.3

In addition, Examples 93-100 further describe combinations of preferred conditions for the preparation of small particle size alloy A: using reaction temperatures of 60-80 ° C, reaction times of 1.5 to 7.0 hours, and the following molar ratios:

Water / sodium oxide 15.0 - 25.0

Sodium oxide / silica 1.6 - 2.4

Silica / alumina 1.0 - 1.5

The following example illustrates the activation of a silicate solution with alumina.

Example 101

A sodium silicate solution consisting of 3.4% sodium oxide and 8.5% silica was activated with 600 ppm alumina from sodium aluminate solution. At 70 ° C, a sodium aluminate solution, also at 70 ° C, consisting of 24.2% sodium oxide and 8.3% alumina, was added to the sodium silicate in thirty to ten seconds. The resulting gel was broken by stirring until a homogeneous slurry was obtained. The batch was then reacted at 80 ° C for 2.5 hours. The total batch composition had a molar ratio of water to sodium oxide of 25: 1, a molar ratio of sodium to silica of 2: 1 and a molar ratio of silica to alumina of 3: 1. The resulting product was zeolite A with a calcium ion exchange capacity of 277 and a magnesium ion exchange capacity of 175. The resulting zeolite particles had a narrow weight% Gaussian distribution, an average particle size of 1.1 microns, and at least 90% by weight between 0.1 and 2.0 microns. The cumulative percentage population was 78% less than one micron and no more than 2% larger than 1.6 microns.

30 69823

Water softening compositions

As already mentioned above, the small particle size zeolites of the invention are useful in a number of areas. Thus, a water-soluble emollient composition comprising a binder, a solubilizer, water, and zeolites of the present invention can be formed. In these compositions, sodium silicate can be used as a binder with a ratio of agent, silica to sodium oxide in the range of 1: 1 to 3.3: 1, preferably about 2.5: 1, as this is the most common molar ratio in detergent compositions. At least 1% sodium silicate is required to bind the layer, but more than 20% sodium silicate limits the amount of sodium silicate that can be added to the system without sufficient improvement in layer strength to justify lower aluminosilicate levels. The most preferred binder would be sodium polysilicate with a 2.5: 1 ratio of silica to sodium oxide. About 1-20% of a suitable solubilizing agent should be present, these substances include soluble sodium phosphates, carbonates, bicarbonates, tetraborates, and sodium sulfate. The preferred solubilizing agent is sodium sulfate.

Some water is needed in the water softening layer (mattress). Otherwise, the ion exchange capacity of sodium silicate is reduced. In a preferred embodiment of the present invention, at least 66% by weight (calculated on the anhydrous basis) of the zeolite of this invention is added to 1-20% by weight of sodium sulfate and the remainder is water. This slurry is then dried with a nozzle diffuser in a spray dryer at an inlet temperature below 540 ° C to produce beads. If the beads are dried at temperatures above 540 ° C, some of the ion exchange capacity may be lost.

Detergent Compositions

A detergent composition (detergent composition) having a high magnesium exchange capacity can be formed. The zeolite A of this invention is preferably used by spraying a liquid surfactant onto the zeolite to form a free-flowing powder or pellets. Care must be taken not to exceed the absorbance limit of the pigment. The powder or pellets are then added to the detergent compositions without further drying. The powder or pellets are dry blended into a dry detergent composition.

31 69823

The surfactant may be anionic, nonionic or amphoteric, although the surfactants include higher alkylarylsulfonic acids and their alkali metal and alkaline earth metal salts, such as, for example, sodium dodecylbenzene benzene tetrenesulfonate, sodium tridecyl sulfonate, magnesium tridecyl sulfonate, sodium dodecyl toluene sulfonate, lithium pentadecyl benzenesulfonate, sodium dioctyl benzenesulfonate, disodium dodecyl benzene disulfonate, disodium alkyl esters of disodium diisopropyl

Nonionic surfactants such as products prepared by condensing one or more lower alkyl alcoholamines such as methanolamine, ethanolamine, propanolamine with a fatty acid such as lauric acid, palmitic acid, tall oil fatty acid, abietic acid may also be used. In addition, amphoteric surfactants such as sodium N-coconut beta-aminopropionate, sodium N-tallow-beta-aminodipropionate, sodium N-lauryl-beta-iminodipropionate and the like can also be used.

The use of low particle size zeolite A was evaluated and evaluated by substituting it for phosphate in basic detergent compositions. Washing experiments were performed on a Model 7243 terg otometer. The experiments were run at 0.15% detergent concentrations of 120 and 240 ppm in hard water (Ca: Mg = 2: 1) at 49 ° C. A fifteen minute wash time at 125 rpm and two five minute rinses were used. Washability was determined with dirty cotton test garments, spun dacron, cotton / dacron with permanent press, and unwashed cells (Wash and wear) with cotton shirting fabrics. The washability value was determined using a Gardner Model XL-10 reflectometer to measure reflection before and after washing. The results in Table X | II show that low particle size zeolite A can replace phosphates in detergent compositions and can even improve overall washing performance. This is especially evident in the 240 ppm hardness test. We believe that the advantageous results obtained in these experiments are due to the fact that 32 69823 small particle size zeolite A has the ability to remove both calcium and magnesium ions from solution at very high noosities.

Table XII

Use of low particle size alloy A in detergents 120 ppm hard water 240 ppm hard water * 1 42 * 3 # 4 wt% g wt% g wt% g wt%

Sodium tripolyphosphate 25 0.375 - - 25 0.375 - -

Small particle size zeolite * * A (eg 35) - - 25 0.469 - - 25 0.469

Richonate 45B 12 0.18 12 0.18 12 0.18 12 0.18

Richonal A 5 0.075 5 0.075 5 0.075 5 0.075

Condensate Co 3 0.045 3 0.045 3 0.045 3 0.045

Carboxymethylcellulose 1 0.015 1 0.015 1 0.015 1 0.015

Sodium silicate 15 0.225 15 0.225 15 0.225 15 0.225

Sodium sulphate 39 0,585 39 0,585 39 0,585 39 0,585 - '' Active base

Test results 120 ppm hard water 240 ppm hard water fabric_ # 1 42 = # - 3 # 4% improvement% improvement% improvement% improvement

Cotton 32.8 39.0 33.4 34.1

Spun dacron 3.0 15.8 10.7 42.4

Cotton / dacron pressing 17.8 17.2 18.8 20.2

Cotton shirting fabric, still smooth 22.8 19.9 19.7 24.8

Total washing capacity% 76.4 91.9 82.6 121.5 69823 33

Paper size logos

Paper compositions containing the small particle size zeolites of this invention may also be formed.

The use of low particle size alloy A as a filler in fine paper was evaluated by adding it to various types of paper compositions. These paper raw material compositions included both bleached and unbleached pulps. Test sheets of different basis weights and made from different types of pulps were tested on a Nobel and Wood Sheet machine. These test sheets were tested according to the following TAPPI (The American Pulp and Paper Institute) standards: T-425 m - paper opacity (opacity) T-452 m - paper and board brightness T-410 m - paper and board basis weight

Table XIII shows that the single pass retention of zeolite A is not dependent on particle size and that the retention is significantly higher than that of Hydrex, J.M. Huber Corporation is a registered trademark for amorphous sodium magnesium aluminosilicate. This suggests that the retention of zeolite A is different and that it works better depending on the species than the particle size. It is reasonable to suspect that the retention mechanism is due to the charge effect between the crystalline substance and the mass and not to the mechanical effects. Surprisingly, the small particle size zeolite A of the present invention showed clearly better optical effects in both brightness and opacity than commercial zeolite A and was as good as the best synthetic agent used for this purpose (Hydrex).

69823 34

Table XIII

Low use of particle size alloy A as a filler in fine paper

m2 weight Retained- PIN PIN

% filling 25x38x500 now pig- clear- translucent-

Pigment substance 'fr /, REAM g / ny ment% seasonality

No filler 50.9 75.3 85.0 82.8

With a small particle size 3 52.1 77.1 58 86.7 86.5

Zeolite A 6 50.2 74.3 55 88.2 89.0.

(eg 10) 9 51.3 75.9 53 89.3 90.6

Commercial 3 50.8 75.2 56 85.6 84.6

Zeolite A 6 52.2 77.3 55 86.1 86.1 9 53.5 79.2 56 86.5 87.2

No filler 48.9 72.4 85.5 .82.2

With a small particle size 3 31.5 76.2 41 87.4 86.1

Zeolite A 5 51.3 75.9 38 88.8 88.5 (eg 10) 9 51.4 76.1 34 89.9 90.1

Hydrex * 3 50.1 74.1 28 87.4 86.1 6 50.2 74.3 30 '88.7 88.2 9 49.8 73.3 31 89.6 89.4 JM, Huber Corporation Registered Trademark 35 6 9 8 2 3 The use of the low particle size alloy A of this invention as an extension of titanium dioxide in paper was evaluated by adding it into a paper raw material composition made of bleached pulp. The paper raw material was 50% bleached hardwood and 50% bleached softwood sulfate cellulose (Kraft). Handmade test sheets were made and their properties were tested by the methods already described above. Table XIV shows the one-time retention of zeolite A in combination with titanium dioxide. This information also suggests a different retention mechanism and confirms the results obtained in the single filler system. The optical properties obtained using the low particle size zeolite A were significantly better than the larger particle size material (commercial zeolite A) and as good as Hydrex.

36 69823

Table XIV

Use of low particle size zeolite A as an extension of titanium dioxide in fine paper 2

m weight Restrained PIN PIN

Filling- 25x38x500 „pigment clear translucent -Pjmentment substance it / REAM g / m% Vans mat

No filler 50.9 75.3 85.0 82.8 50% with a small particle size of 3 5Ö. 6 74.9 61 8 7.8 88.4

zeolite A

6 51.0 75.5 58 89.6 91.9 (e.g. 10) and 50% titanium dioxide 9 50.7 75.0 55 90.8 93.8 50% commercial 3 50.5 74.7 59 87.2 87.7 zeolite A and 6 51.3 75.9 60 88.7 91.0 5Q% titanium dioxide 9 51.4 76.1 60 89.7 92.9

No filler 43.9 72.4 85.5 82.2 su * of small particle size 3 51.5 76.2 47 88.3 88.2

zeolite 'A

(e.g. 10) 6 51.0 75-5 42 89.8 91.4 and 50% titanium dioxide 9 50.3 74.4 40 '90.9 93.4 50% Hydrex 3 50.3 74.4 24 88.3 88.5 and 50% titanium dioxide 5 49.9 73.9 36 89.8 91.7 9 49.5 73.3 39 90.9 93.5 37 69823

The use of low particle size zeolite A as a filler in newsprint was evaluated by adding it to a standard newsprint feedstock. Newsprint sheets were made by hand, the raw material of which consisted of 65% wood chips and 35% semi-bleached sulphate cellulose (Kraft paper), the sheets were made using a machine Noble and Wood Sheet machine. The sheets were printed using 1.7 and 2.5 g of ink per square meter on a Vandercook Proofing Press with a massive block and M-mill compression pressure. After 24 hours, brightness readings were taken on the opposite side of the printed and unprinted sheet. These were recorded and the results were reported as breakthrough values with 20 grams of ink per square meter (a modified version of the Larocque breakthrough test).

The data in Table XV also show that the retention mechanism of zeolite A is different from other specialty fillings commonly used in newsprint applications. The results also confirm that low particle size zeolite A is superior to commercial zeolite A and is advantageous compared to Zeolex 23 from J.

M. Huber Corporation is a registered trademark of amorphous sodium aluminosilicate.

69823 38

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39 69823

The use of low particle size zeolite A in paper coatings was tested in various coating recipes. Two of these are given below: 1. 87% hydrosperse clay 5% titanium dioxide 8% pigment 2. 92% hydrosperse clay 8% pigment These compositions were prepared at 58% solids using 16 parts per 100 binder levels (75% starch to 25% latex) and ground using a Cowles Dissolver. The paper used was 32 φ substrate coated on 13 * 307 square meters using a Keegan Laboratory Trailing Blade Coater. All sheets were supercalendered, 3 nips at 66 ° C and 2,690 kN / m. The sheets were then inspected for gloss, opacity and brightness using the following TAPPI standards: T-480m paper gloss T-425m paper opacity T-452 the brightness of paper and board

The results in Table XVI show that low particle size zeolite A is superior to commercial zeolite A. This is evident in better gloss development, but is also a significant improvement in both brightness and opacity when used either as an extension to titanium or as a filler. Similar effects were observed in tests performed on coated cartons.

Table XVI

Use of low particle size alloy A as an extension of titanium dioxide in paper coatings (87% hydrosperse clay - 5% TiO, ^ 8% pigment)

75 degrees PIN PIN

Pigment Gloss% Brightness Opacity

Zeolite A with a small particle size of 64.9 71.1 90.9 (Example 10)

Commercial 55.0 70.4 90.3

zeolite A

69823

Use of low particle size alloy A as a pigment in paper coatings (92% hydrsperse clay - 8% pigment)

75 degrees PIN PIN

Pigment Gloss% Brightness Opaque small particle size 64.0 69.3 89.0 zeolite A (Example 10)

Commercial 55.9 68.1 88.5

zeolite A

Rubber blessings

A rubber composition containing zeolite A can be formed.

The rubbers (referred to herein as elastomers, which are unvulcanized) that can be used in this invention include both natural rubbers and synthetic rubbers. Examples of suitable synthetic rubbers are styrene butadiene, butyl rubber, nitrile rubber, polybutadiene, polyisoprene, ethylene propylene, acrylic, fluorocarbon rubbers, polysulfide rubbers and silicone rubbers. Mixtures of the above copolymers of synthetic rubbers can be used alone or in combination with natural rubber. Preferred rubbers are nitrile rubber, styrene-butadiene rubber, natural rubber, polyisoprene and mixtures thereof, as they are the most compatible (compatible) with polyester fibers, although small amounts of other rubbers can be included without adverse effects. U.S. Patent 3,036,980 discloses rubber compositions containing zeolites.

plastic compositions

A plastic composition containing zeolites having a small and uniform particle size, such as zeolite A, can be formed.

Non-settable dimming pigment The zeolite A of the present invention can also be used as a non-settling dimming pigment.

Small particle size zeolite A was evaluated as a non-settable opaque pigment in nitrocellulose varnish and as an extension of the main pigment in opaque latex paint systems. Tests in the nitro-69823 cellulose varnish system were performed by adding zeolite to the varnish. The amount of zeolite used was equivalent to 10% by weight of the carrier solids. The varnish and zeolite were mixed together using a Hamilton Beach Model 936 Blender at 16,000 rpm for four minutes and the resulting mixture was sieved through a fine paint sieve. The Hegman grind was determined in the usual manner and the mixture was then drawn onto a Leneta 5c paper panel using a - = f34 vanungil-la twisted coating rod. The panels were dried at room temperature for 45 minutes in a dust-free state in an upright position.

The Gardner polygon gloss meter was used to determine gloss (60 degrees (degree head)) and gloss (85 degrees (degree head)) from the panels. Landing was assessed using an accelerated test on an approximate scale of 0 (failed) .... 10 (not at all) after 7 days at 49 ° C.

The results in Table XVII show that small particle size zeolite A was superior to commercial zeolite A in all categories and the exceptional clarity of its lacquer, which contained small particle size zeolite A, is of significant value in special applications.

Table XVII

Use of low particle size alloy A without settling dimming pigment. in nitrocellulose varnish Sample Hegman 6 0 ° gloss 85 ° gloss Landing

Small particle size zeolite

(Example 10) 6.25 15 27 8

Commercial zeolite A 6.00 33 71 1

The use of low particle size zeolite A as an extension of the main pigment in a matte latex paint system was evaluated as follows: “2 69823

Part I of the composition was mixed, then Part II of the composition was added and the whole mixture was stirred for 10 minutes in a Cowles in a high speed mixer. Zeolite A was added at this time and dispersed for 5 minutes. The diluent (Part III) was then added to the entire composition and mixed for an additional 5 minutes. The resulting paint was applied to Leneta IB paper panels using a coating rod twisted with ^ 34 vanung. The panels were dried at room temperature under dust-free conditions in an upright position. A Gardner moniku.l gloss meter was used to determine the gloss and sheen of oanels.

The results are shown in Table XVIII and the compositions in Table XIX.

Table XIX

Use of low particle size zeolite A as an extension of the main pigment in opaque latex systems

Brightness Contrast 60 ° 85 ° Sample YB_ ratio_ Gloss Glow small particle size zeolite A 89.6 0.968 3 7 (Example 10)

Commercial zeolite A 87.6 0.958 3 4

The results in Table XIX show that low particle size zeolite A has better performance than commercial zeolite A as an extension of the ice pigment in this paint system. the recession is evident in terms of brightness and contrast ratio, indicating that small particle size zeolite A is significantly more efficient and has better optical properties.

69823 43

Table XVIII

Weight, g Weight, g

Composition 1 2

Part I

Water 200 200

Cellosize 0P-15000 0.5 0.5 AMP-95 2 2

Daxad 30 8 8

Ethylene glycol 17 17

Super Ad It 1 1

Napco NDW 1 1

Part II

R-901 150 150

Huber 70C 100 100 G-white 150 150

Small particle size zeolite

(e.g. 10) 60 ---

Commercial zeolite A --- 60

Part III

Water 183 183 QP-15000 3 3 AMP-95 3 3

Texanol 8 8

Napco NDW 2 2

Amsco 3011 264 264

Claims (5)

1. Zeolite A of liter »and uniform particle size and high magnesium exchange capacity, which zeolite A is produced by reaction of a sodium silicate and a sodium aluminate, characterized in that the zeolite particles exhibit a narrow differential weight percent Gaussian distribution with an average particle size of high average particle size. and at least 90% by weight of the particles is between 0.1 and 4.0 microns, with at least 35% of the particles exceeding one micron and at most 5% of the particles exceeding 5 microns in the cumulative percent population, the calcium carbonate exchange capacity Sr higher than 230 mg of calcium carbonate per gram of zeolite and the magnesium carbonate exchange capacity is higher than 90 mg of magnesium carbonate per gram of zeolite. 2. An improved process for producing a sodium aluminum silicate zeolite A according to claim 1 by reacting a sodium aluminate and a sodium silicate by admixing an aqueous solution of the sodium aluminate and an aqueous solution of the sodium silicate, and reacting at a temperature of 40 ° C. 12C ° C, thereby forming an amorphous sodium aluminum silicate, and then reacting the mixture at a temperature slightly above said mixing temperature, thereby forming crystalline sodium silicate zeolites, characterized in that the aqueous solutions of the sodium silicate are mixed, and the sodium silicate is mixed. a reaction mixture, the reaction reaction components have the following molar ratios: (1) water to sodium oxide 10: 1-35: 1 (2) sodium oxide to silica 1: 1-2.5: 1 (3) silica to alumina 3: 1-8 : 1 and further, since when the mole ratio of silica to alumina is 2.0: 1 or below, the maximum temperature of the reaction is in fall 80 ° C. Process according to claim 2 for the manufacture of zeolite A, characterized in that the reaction components of the reaction mixture have the following molar ratios: water to sodium oxide 15: 1-20: 1, sodium oxide to silica 1.2: 1-3: 1 and silica to alumina 2: 1-7.3: 1.