RU2279416C2 - Ammonium sulfate nitrate composition and method of production of such composition (versions) - Google Patents

Abstract

FIELD: sulfate nitrate compositions used as fertilizers.

SUBSTANCE: proposed ammonium sulfate nitrate composition contains ammonium sulfate and (NH₄)₂SO₄·2 (NH₄NO₃)salt with at least 5%-mass of more dangerous (NH₄)₂SO₄·3(NH₄NO₃) salt and ammonium nitrate. Composition is obtained through reaction of ammonium sulfate with ammonium nitrate taken at mole ratio of from 0.9:1 to 1.1:1 in presence of small amount of water within limited temperature range; then, fast cooling is performed for hardening to avoid macroscopic separation of reaction products. Proposed composite material of ammonium sulfate and ammonium nitrate is used as fertilizer.

EFFECT: possibility of obtaining required levels of nitrate ions; high resistance to detonation, high density, high resistance to moisture.

22 cl, 7 dwg, 9 tbl, 4 ex

Description

1. Field of invention

The present invention relates to sulfate-nitrate composite materials used as fertilizers having the desired levels of nitrate ions, very high stability against detonation, higher density, greater resistance to moisture. The invention also relates to a method for producing said fertilizers.

2. Description of the prior art

Ammonium Nitrate Sulfate (ASN) is one of the first synthetic fertilizers to be used continuously for nearly 100 years, providing plants with important primary and secondary nutrients, nitrogen and sulfur. Nitrogen is partially provided through the nitrate ion, which is desirable because it is easily adsorbed by many plants, promoting their growth at an early stage. Historically, the term “ammonium sulfate nitrate” does not refer to a specific chemical compound containing elements in fixed ratios. Rather, it was used to describe various mixtures of ammonium sulfate and ammonium nitrate. The Fertilizer Control Association of American Plant Food Manufacturers (AAPFCO) has attempted to introduce refinements in line with the nomenclature. AAPFCO defined ASN as a double salt of ammonium sulfate and ammonium nitrate in equal molar proportions having a nitrogen content of at least 26%. A mixture of ammonium sulfate and ammonium nitrate, taken in equal moles, has a nitrogen content of 26.4%.

Despite the definition of AAPFCO, the name ammonium sulfate is used to define many combinations of ammonium sulfate and ammonium nitrate. See, e.g., R.S. Meline, J.Aqric. Food Chem., 16 (2), 235-240 (1968), where one product has a 30% nitrogen content. US 2,795,495 describes ammonium nitrate sulfate as having a molar ratio of ammonium sulfate / ammonium nitrate of 1: 2 rather than 1: 1. GB 798 690 determines that the proportion of ammonium sulfate is not critical, and it can be used in any proportion necessary to obtain the desired level of nitrogen. The use of such terminology has led to confusion between pure binary salts and mixtures. In addition, in the prior art, the word order of sulfate and nitrate is sometimes changed.

Double salt is a specific compound. The definition of AAPFCO implies the existence of a compound consisting of one mole of ammonium sulfate and one mole of ammonium nitrate. Such a compound was reported, however, a 1: 1 double salt was not isolated and its existence was not conclusively proven. Nikonova et al., Zhurnal Prikaladnoi Khimii 15 (6). 437-446 (1942) provides a critical analysis and corrects early work.

Simple mixing of ammonium sulfate and ammonium nitrate does not lead to a reaction or to the completion of a reaction between them. Sufficient conditions, including time, must be met to cause a complete chemical reaction between the two starting salts. However, even under ideal conditions, the reaction taken in equal molar ratios of ammonium sulfate and ammonium nitrate does not end with the formation of a compound containing equal moles. Instead, the reaction products are double salts with different proportions mixed with unreacted ammonium sulfate and / or ammonium nitrate.

Double salts consisting of NH ₄ SO ₄ · 2 (NH ₄ NO ₃ ) and NH ₄ SO ₄ • 3 (NH ₄ NO ₃ ) (hereinafter the 1: 2 double salt and the 1: 3 double salt, respectively) were isolated and characterized by. Product 1: 3 was isolated from an aqueous solution and was already reported in 1909 (Reicher et al., Chemish Weekblad. 3 (Jan.). 51-56 (1909)). Scheinemakers et al. reported in 1910 in the same publication (Volume 6, 1910, pages 51-56) about the allocation of a double salt of 1: 2, as well as about a double salt of 1: 3, from aqueous solutions.

The existence of double salts 1: 2 and 1: 3 was confirmed by Nikonova (loc. Cit.}; Itoh, Koqyo Kaqaku Zasshi. 63 (11), 1913-1916 (1960); Emons et al., Wissenschaftliche. Zeitschrift Techn. Hocksch, Chem. Leuna-Merseburg, 14 (3). 295-299 (1972); and Smith et al., J. Agr. Food Chem., 10, 77-78 (1962), among other publications.

Reported production methods describe the preparation of uniform fertilizer granules from ammonium nitrate sulfate. Most products are simply mixtures of ammonium sulfate and ammonium nitrate, and not specific crystal structures, since the reported chemical compositions do not reflect any specific compounds. An exception is US Pat. No. 2,762,699, issued for the 1: 2 double salt manufacturing process.

The processes of crystallization, granulation and prilling (the formation of granules by curing droplets during spraying of molten salts) have been described. GB 798690 describes a method of crystallization from an aqueous solution of ammonium sulfate and ammonium nitrate. Typically, granulation processes use temperatures below the melting point of ammonium nitrate (170 ° C), which ensure that the product is fully reacted. Examples of granulation processes are given in US 3635691, GB 893389, DE 1039498, GB 1259778 and in the previously mentioned journal article R. S. Meline, et. a1. In prilling processes, temperatures that are above the melting point of ammonium nitrate (170 ° C) are used. Examples are given in Polish Patent PL86.766 and in Przem. Chem., 55 (12). 611-614 (1976). A small amount of water was added to facilitate the melting of nitrate. Swedish Patent 70,119 describes a process for using up to 10% water in a feed consisting of ammonium sulfate and ammonium nitrate in a molar ratio of 0.6: 1 and prilling.

Several details were reported regarding the composition of the products obtained in these processes. Most, if not all, are mixtures of binary salts, ammonium sulfate and ammonium nitrate.

From the prior art it becomes clear that the products of these processes are characterized by low resistance to destruction, a tendency to adsorption of moisture and sintering. For example, in FP 1368035 they say that fertilizer - ammonium sulfate nitrate is not stable during storage. Belgian patent 388046 lists several methods that use additives to eliminate these problems. The tendency to sintering due to absorption of moisture decreases with the addition of amphoteric metal oxides. US 2795495 describes a process for improving the stability of ammonium nitrate sulfate by adding iron salts after exposure to ammonia. GB 1259778 describes a composition comprising aluminum hydroxide or aluminum salts to obtain improved anti-sintering properties. GB 372388 improves stability by the addition of urea and magnesium salts.

J. Turlej, Prz. Chem, 55 (12), 611-614 (1976) describes attempts by various manufacturers to increase the stability of ammonium sulfate nitrate. BASF, currently the largest producer, reportedly adds aluminum, magnesium, and / or calcium compounds. Ruhrchemie adds iron sulfate; Victor-Chemische adds iron sulfate; Uhde Hebemia adds iron sulfate and the mineral fanolite. SBA (Belgium) adds some other compounds. Turlej's own work, reported in the same journal article, demonstrates the addition of dolomite, aluminum, and / or magnesium compounds in order to increase stability and eliminate sintering.

Some references indicate that ammonium sulfate nitrate always contains unreacted starting materials. I.G. Farbenindustries reports in DE; 555581 and DE 555902, which is always present free ammonium nitrate. Srinivasa and others report in Technology, 6 (1). 21-23 (1969) that the product always contains free ammonium nitrate. Ammonium nitrate is known to be very hygroscopic and this probably contributes to the birth of sintering problems and particle weakness.

Ammonium nitrate mixed with organic materials such as fuel oil is an important industrial explosive. He is also associated with terrorist incidents, such as the bombing at the New York World Trade and Bombing Center in Oklahoma City. It is desirable to change the state of ammonium nitrate to change the sensitivity to detonation. One way to do this is to dilute ammonium nitrate with a relatively inert material. According to US 3366468, 1968, it is patented that from 5 to 10% of additives such as ammonium phosphates or ammonium sulfate can desensitize and change the resistance of ignition and detonation of ammonium nitrate. However, pure double salts of ammonium sulfate - ammonium nitrate should also be considered as potential explosive materials, because the ratio of oxygen to nitrogen is favorable for oxidation reactions.

Naoum et al., Zeit. fur das Gesamte_Sceiss. Und Sprangstoff. 19, 35-38 (1924) determined the heat of flash (reaction) of ammonium nitrate and mixtures of ammonium nitrate with ammonium sulfate as a function of composition. The latent energies in 64.5 wt.% And 54.8 wt.% Mixtures of ammonium nitrate correspond to double salts 1: 3 and 1: 2, while mixtures of 81% and 76% respectively have explosive energy of pure ammonium nitrate. Data from an independent test lab at Honeywell International has shown that a 1: 3 double salt releases more energy when broken than a 1: 2 salt. However, Naoun et al. indicates that a fully homogeneous mixture containing less than 40 wt.% ammonium nitrate is probably no longer explosive. The latent explosive energy was zero at a molar ratio of the mixture of ammonium sulfate / ammonium nitrate 1: 1 (37.7% by weight of ammonium nitrate). Naoun et al., WO 9961395 A1 also showed that the more homogeneous the mixture of ammonium nitrate and ammonium sulfate, the greater the difficulty in detonation. However, mixtures of ammonium nitrate and coarse-grained ammonium sulfate can produce greater gas expansion upon detonation than ammonium nitrate alone. Therefore, a thoroughly mixed mixture of ammonium nitrate and ammonium sulfate, consisting of very small particles, is most desirable. Binary salts provide molecular homogeneity and dispersion on the scale of several angstroms. Conditions sufficient for the reaction of ammonium sulfate with ammonium nitrate, maintained for a sufficient period, convert ammonium nitrate almost completely into binary salts. Such a reaction, if carried out with a sufficient molar excess of ammonium sulfate, leads to a complete or almost complete conversion to a more reliable 1: 2 double salt.

Ammonium sulfate nitrate fertilizer is currently produced and sold by BASF and Fertiberia. An X-ray diffraction analysis of the product obtained by BASF shows that it is a composition consisting of on average 27 wt.% Ammonium sulfate, 1 wt.% Double salt 1: 2 and 72 wt.% Double salt 1: 3. The product of the company Fertiberia consists of 29 wt.% Ammonium sulfate, 35 wt.% Double salt 1: 2 and 36 wt.% Double salt 1: 3. These products are apparently made using a granulation process. Granules have a heterogeneous surface of the core.

The nutritional value, safety, and stability of ammonium nitrate sulfate compositions are competitive. Nutritional value increases with increasing nitrate content, but also increases sensitivity to detonation and sensitivity to moisture. In view of the high fine for detonation, it was noted that the balance between these properties should be where confidence in safety is necessary. The preceding conclusions lead to the view that the product ammonium sulfate nitrate containing the maximum amount of nitrate compatible with safe properties is necessary.

SUMMARY OF THE INVENTION

An object of the present invention is an non-explosive composite material ammonium nitrate sulfate containing, as shown by x-ray diffraction from about 14 wt.% To about 35 wt.% Ammonium sulfate ((NH ₄ ) ₂ SO ₄ ); from about 60 wt.% to about 85 wt.% (NH ₄ ) ₂ SO ₄ · 2 (NH ₄ NO ₃ ) double salt; and from 0 to about 5 wt.% in the amount of (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) double salt and ammonium nitrate (NH ₄ NO ₃ ). Compositions useful as fertilizers have a reduced moisture sensitivity, are not considered hazardous materials under number 49 in the Code of Federal Regulations, "Transportation", Part 172, "Hazardous Materials Table", October 1, 2000 and are not classified as oxidizing agents according to United Nations Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria, 1995 "," Section 34, Classification Procedures, Test Methods and Criteria Relating to Oxidizing Substances of Division 5.1 ".

The invention is also a method for producing composite materials comprising ammonium nitrate sulfate comprising loading particles of ammonium sulfate, ammonium nitrate and water into a melting device in which the molar ratio of ammonium sulfate to ammonium nitrate is from about 0.9: 1 to about 1.1: 1, and water comprises from more than 2 wt.% to about 10 wt.% of the loaded materials; (b) melting ammonium nitrate and dissolving at least a portion of the particles of ammonium sulfate at a temperature of from about 180 ° C to about 210 ° C; (c) the interaction of the loaded products at a temperature of from about 180 ° C to about 210 ° C; and (d) solidification of the product at a cooling rate of at least about 100 ° C / min.

The invention also includes a composite material of ammonium sulfate, obtained by a method comprising the steps of: (a) loading particles comprising ammonium sulfate, ammonium nitrate and water into a melting device in which the molar ratio of ammonium sulfate to ammonium nitrate is from about 0.9: 1 to about 1.1: 1 and water is from more than 2 wt.% to about 10 wt.% of the loaded materials; (b) melting ammonium nitrate and dissolving at least a portion of the particles of ammonium sulfate at a temperature of from about 180 ° C to about 210 ° C; (c) the interaction of the loaded products at a temperature of from about 180 ° C to about 210 ° C; and (d) solidification of the product at a cooling rate of at least about 100 ° C / min.

BRIEF DESCRIPTION OF FIGS. 1-7

Figures 1-3 show X-ray diffraction spectra of Cu Kα ₁ for a composite material ammonium sulfate, containing, as shown by X-ray diffraction, 7.6 wt.% Ammonium sulfate, 42.4 wt.% (NH ₄ ) ₂ SO ₄ · 2 (NH ₄ NO ₃ ), 45.7 wt.% (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) and 4.3 wt. ammonium nitrate.

The figure 1 shows a scan of the x-ray diffraction spectrum for the specified composite material ammonium sulfate nitrate in an angular range from 18.2 ° to 21 °

The figure 2 shows a scan of Cu Kα ₁ X-ray diffraction spectrum for the specified composite material ammonium sulfate nitrate in the angular range from 30.4 ° to 31.8 °

The figure 3 shows a scan of Cu Kα ₁ X-ray diffraction spectrum for the specified composite material ammonium sulfate nitrate in the angular range from 31.8 ° to 33.8 °

4 is a graph illustrating the relationship between the amount of water in the charge and the percentage of 1: 2 double salt in the product.

Figure 5 is a graph illustrating the relationship between the amount of water in the charge and the percentage of double salt 1: 3 in the product.

6 is a graph illustrating the relationship between the amount of water in the charge and the percentage of ammonium nitrate in the product.

7 is a graph illustrating the relationship between the amount of water in the charge as formed in the product and the percentage of 1: 2 double salt in the product.

DETAILED DESCRIPTION OF THE INVENTION

The object of the present invention is a composite material, ammonium nitrate sulfate, characterized by x-ray diffraction, as containing from about 14 wt.% To about 35 wt.% Ammonium sulfate ((NH ₄ ) ₂ SO ₄ ); from about 60 wt.% to about 85 wt.% (NH ₄ ) ₂ SO ₄ · 2 (NH ₄ NO ₃ ) double salt; and from 0 to about 5 wt.% in the amount of (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) double salt and ammonium nitrate (NH ₄ NO ₃ ). It is preferred that the composite material ammonium nitrate sulfate is characterized by X-ray diffraction as consisting essentially of about 14 wt.% To about 35 wt.% Ammonium sulfate ((NH ₄ ) ₂ SO ₄ ); from about 60 wt.% to about 85 wt.% the weight of (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) double salt; and 0 to about 5 wt.% in the amount of (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) double salt and ammonium nitrate (NH ₄ NO ₃ ).

It is preferable that in the sum of (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) the double salt and ammonium nitrate (NH ₄ NO ₃ ) in the composite material, the ammonium sulfate of the present invention is from 0 to about 3 wt.% More preferably ammonium nitrate ((NH ₄ NO ₃ ) is from about 0 to 1 wt.%

The term “double salt” as used in the present invention means a chemical compound composed of ions of two preceding compounds, whose crystalline structure differs from the structure of the preceding compounds. The molar ratio of precursor compounds in the double salt is in the ratio of small integers, for example 1: 2, and is not continuously variable as in solid solution.

The composite product according to the invention consists of small crystals of ammonium sulfate embedded in the composition (matrix) of other components. The composite material of the invention must be distinguished from a mixture of free particles. The volume of the crystals of ammonium sulfate is approximately the same as the particles of the starting ammonium sulfate, but when solidified, about 5 wt.% Of the precipitate in the form of crystals has a size of less than about 2 microns. Ammonium sulfate crystals are dispersed uniformly in the composition. The small size and uniform dispersion of crystals of ammonium sulfate in a double salt of 1: 2 significantly increases the stability of the product with respect to the danger of detonation.

Less than about 5% by weight of the product consists of hazardous ammonium nitrate or 1: 3 double salt particles. The compositions of the invention are useful as fertilizers, they 1 reduce moisture sensitivity, are not considered hazardous materials in Title 49 of the Code of Federal Regulations, "Transportation", Part 172, "Hazardous Materials Table", October 1,2000 and are not classified as oxidizing agents according to the United Nations Recommendations on the Transport of Dangerous Goods, Manual of Tests and Criteria, 1995 "," Section 34, Classification Procedures, Test Methods and Criteria Relating to Oxidizing Substances of Division 5.1 ".

Ammonium sulfate and ammonium nitrate, which are used to form the compositions of the invention, are purified fertilizers of at least about 90% purity. Preferably, ammonium sulfate and ammonium nitrate are at least about 95% pure. More preferably, ammonium sulfate and ammonium nitrate have at least 97% purity. Because of the danger of mixing organic materials with ammonium nitrate, it is highly desirable that neither ammonium sulfate nor ammonium nitrate contain more than about 0.2 wt.% Organic contaminants. One example of the ammonium sulfate used in the invention is a commercially available product from Honeywell International Inc.

The particle size of ammonium nitrate is not critical, but preferably it is about 95% by weight of ammonium nitrate particles passing through a Tyier No. sieve. 6 (hole in 3.36 mm).

The particle size of ammonium sulfate is important to achieve the objectives of the invention. As a rule, the smaller the particle, the higher the reaction rate between ammonium sulfate and ammonium nitrate and the higher the degree of dispersion. Preferably, at least about 85% by weight of ammonium sulfate is passed through a Tyler No. 48 sieve (0.030 mm hole). Ammonium sulphate, milled in a ball mill, usually meets this criterion without additional screening. More preferably, about 99% by weight of ammonium sulfate is passable through a Tyler No. 48 sieve. Most preferably, about 99% by weight of ammonium sulfate is passable through a Tyler No. 48 sieve and about 50% by weight is passable through a Tyler No. 200 sieve. (hole in 0.074 mm).

The compositions of the invention are formed by reacting ammonium sulfate with ammonium nitrate at a molar ratio of from about 0.9: 1 to about 1.1: 1 in the presence of a small amount of water in a narrow range of temperature fluctuations, and then cooling to solidify at a sufficiently fast rate to prevent macroscopic segregation reaction products. It was found that at a cooling rate of less than about 100 ° C / min, a tendency to phase separation is observed. The method according to the invention includes the steps of: (a) loading products comprising particles of ammonium sulfate, ammonium nitrate and water into a melting device in which the molar ratio of ammonium sulfate to ammonium nitrate is from about 0.9: 1 to about 1.1: 1 and water is more than 2 wt.% to about 10 wt.% of the loaded products; (b) melting ammonium nitrate and dissolving at least a portion of the particles of ammonium sulfate at a temperature of from about 180 ° C to about 210 ° C; (c) the interaction of the loaded products at a temperature of from about 180 ° C to about 210 ° C; and (d) solidification of the product at a cooling rate of at least about 100 ° C / min.

Preferably, the method of the invention is conducted as a continuous process.

In another embodiment, the invention includes the production of ammonium nitrate sulfate using a process comprising the steps of: (a) loading products consisting essentially of particles of ammonium sulfate, ammonium nitrate and water into a melting device in which the molar ratio of ammonium sulfate to ammonium nitrate is from about 0.9: 1 to about 1.1: 1 and water is from more than 2 wt.% to about 10 wt.% of the loaded materials; (b) melting ammonium nitrate and dissolving at least a portion of the particles of ammonium sulfate at a temperature of from about 180 ° C to about 210 ° C; (c) the interaction of the loaded products at a temperature of from about 180 ° C to about 210 ° C; and (d) solidification of the product at a cooling rate of at least about 100 ° C / min.

The ranges of the melting temperature and the reaction of interaction are limited by the need for melting ammonium nitrate, as well as the need to reduce its decomposition. Preferably, the melting and reaction temperatures are from about 190 ° C to about 205 ° C. More preferably, the melting points and the reaction are from about 190 ° C to about 200 ° C.

The time provided for the reaction between ammonium sulfate and ammonium nitrate is not critical, provided that a substantial time is provided for the dissolution of ammonium sulfate. The rate-reducing stage is believed to be the dissolution of ammonium sulfate in the molten ammonium nitrate. The required dissolution time will be lower with finer particles of ammonium sulfate, with vigorous stirring of the melt and with temperatures at the higher end of the allowable range.

For agricultural purposes, it is preferred that the products of the invention are in the form of free-flowing granules. Preferably, step d) of the process of the invention: solidification of the product at a cooling rate of at least about 100 ° C./min is carried out in a granulation column. The cooling rate will be greater at lower droplet sizes and lower air temperatures in the pellet formation column.

Water is an essential component of the reaction mixture. Surprisingly, a sharp change occurs in the ratios of 1: 2 and 1: 3 of double salts in the product, when the water content in the charge exceeds about 2 wt.%. When the water becomes less than about 2 wt.% Of the loaded products, a more dangerous double salt 1: 3, in the preference of the more desirable double salt 1: 2 and there remains a greater amount of unreacted residues of ammonium nitrate. Preferably, the water content is greater than 2 wt.% To about 5 wt.% Of the volume of the loaded products. More preferably, the water content should be about 2.5 wt.% To about 4 wt.% From the loaded products.

The method in which water is charged into the reaction mixture is not critical. Water can be charged as a liquid, or it can be incorporated into ammonium sulfate, ammonium nitrate, or both in the form of adsorbed moisture.

It is also surprising that the residual water in the product after melting and cooling is proportional to the initial amount of water, even though in some examples, the melting was carried out at a temperature of 200 ° C for more than an hour with stirring. The concentration of residual water was also surprisingly high, given the high pressure of water vapor at a temperature of 200 ° C. Most of the added water probably evaporates quickly, but the final ratios of the double salts are strongly related to the concentration of water remaining in the product.

Another amazing effect of water has also been discovered. At the temperatures used in melting, water may create bubbles (voids), resulting in a lower density. Contrary to expectations, the density of the product increased with an increase in the amount of residual water.

Without being bound by a specific theory that reveals the essence of the invention, it is hypothesized that ammonium sulfate, which is in an equipolar mixture of ammonium sulfate and ammonium nitrate, is not completely soluble in molten ammonium nitrate in the absence of water. This limits the reaction of ammonium sulfate with ammonium nitrate, leads to a tendency to form a residue of ammonium nitrate, and therefore contributes to the formation of a higher content of 1: 3 double salt nitrate. When water is added to the charge, it is assumed that the solubility of ammonium sulfate in molten ammonium nitrate increases, thereby helping to complete the reaction of ammonium nitrate with ammonium sulfate and the formation of a double salt of 1: 2.

The compositions of the invention are analyzed by X-ray powder diffraction (XRD) to determine the ratios of ammonium sulfate, ammonium nitrate, double salts 1: 2 and 1: 3. The data in the examples were collected on a 1700 Phillips APD system x-ray diffractometer with the following characteristics.

XRD Hardware

- Sealed tubular XRG 3100 generator with Cu target, using a power of 50 kW, a current of 40 mA.

- A vertical diffractometer in the geometry of parafocus.

- Alternating falling, longitudinal section (compensation θ).

- Curved graphite monochromator in a set of diffracted beam for Cu Kα.

- 0.2 °, obtained longitudinal section.

- Sealed proportional xenon counter.

- Automatic fixture for sample replacement.

- PC-APD software.

Samples and standards for XRD analysis were ground to particle sizes of less than 40 microns using an 8000 SPEX Mill, Wig-L-Bug shredder or mortar and pestle, and then loaded into standard racks. Small particle sizes and reloading were used to reduce any effects associated with preferred orientation or microadsorption.

Compounds and their diffraction peaks were identified using the standard research procedure and the powder diffraction database International Center For Diffraction Data (ICDD), Newton Square, PA. The initial scan of the spectra of the comparison products and their mixtures with the standard - aluminum oxide - was collected in the angular range from 5 ° to 85 ° 2θ, using 0.02 ° 2θ step sizes from 1 with a counting system.

Diffraction spectrum scans were tailored to the profile using Philips software. The profile landing program used the Marquardt non-linear least squares algorithm, Voigt peak profile and linear background. Suitable results for each diffraction maximum consisted of its 2θ peak positions for Cu Kα ₁ using λ = 1.54056 Å, full width at half maximum (FWHM) Kα ₁ peak component, peak height Kα ₁ peak component, area Kα ₁ peak component and total area peak, which includes the contribution of both Cu Kα ₁ and Kα ₂ wavelengths. FWHMs have not been fixed for hardware expansion.

Quantitative studies were performed using the adjusted profile peak height and the area of the selected diffraction maxima for each compound and Reference Intensity Ratios (RIR). RIR compounds were determined by measuring the ratio of their intensity to that of the internal mixture of the reference standard alumina. NBS 674a, from MIST, using both variable length cuts and the estimated set intensity of a longitudinal cut containing known phase to alumina ratios. Mixtures of ammonium sulfate, ammonium nitrate and double salts with alumina were prepared in weight ratios of 25/75, 50/50 and 75/25.

An X-ray scan for RIR determination was made from 5 ° to 45 ° 2θ with 0.02 ° 2 step sizes.

RIR for ammonium nitrate was obtained using ammonium nitrate brand ACS Grade as certified by Fisher Scientific. The ammonium sulfate used for the RIR determination was commercially available from Honeyweli International Inc. The Hopewell VA plant has a purity of about 98 wt.%. The standards used to determine the RIR values for 1: 2 and 1: 3 double salts were made by crystallization and correlation for impurities in the samples. 1: 2 Standard contained 16.7% ammonium sulfate. 1: 3 The standard contained about 1-2% ammonium sulfate and about 3% ammonium nitrate.

Most peaks in the scans of these mixtures were set between 15 ° and 45 ° 2θ. For each phase, the relative intensities (in%) of their diffraction peaks were determined experimentally against its most intense peak. The relative intensities for each phase were calculated for three intensity parameters: Kα ₁ peak height, Kα ₁ peak area and total peak area using the average number of intensities from the pure analytical standard and its mixtures with alumina. The relative intensities of the peaks of alumina were determined for each phase, using averaged intensities from pure alumina and its mixtures with this phase.

In the prior art, the relative intensities of XRD samples and their RIRs are given based on fixed intensities of the longitudinal section. Since experimentally obtained intensity data were collected using a variable longitudinal section, the fixed intensities of the longitudinal section were calculated using the following equation:

I (fixed) = I (variable) / sinθ

In general, the three most intense peaks for each phase were used to determine RIR. For each mixture, the intensities from the peaks were normalized using their relative intensities. The average number of their normalized intensities for the analytical phase and alumina 1 (a) and 1 (s), respectively, were then used in the RIR calculation:

where X (s) = mass fraction of alumina

X (a) = mass fraction of the analytical phase.

The RIRs from the mix set were then averaged and the tolerance determined. RIRs were determined for both a variable longitudinal section and a fixed longitudinal section and for all 3 intensity parameters: Kα ₁ peak height, Kα ₁ peak area and total peak area.

Table I shows the diffraction maxima used to determine RIRs and their relative intensities. Table II shows the average RIR value, both defined and their tolerances.

Since the products of the examples were 100% crystalline, and all phases are known along with their RIR, it was not necessary to mix the samples with the standard. Instead, the products of the examples were directly measured and mass fractions were calculated using the "Matrix Flushing" ("Normalized RIR") method (R. L. Snyder, Powder Diffraction. 7 (4) 186-193 (1992)). In the matrix method of development with a wet tab (Matrix flushing method), the percentage of mass of the α phase in a mixture of n phases, using the normalized intensity, is calculated based on the following relationship

where the summation is higher than j = 1 to n phases.

Table I Aluminium oxide Ammonium sulfate Ammonium nitrate (NH ₄ ) ₂ SO ₄ • 2 (NH) ₄ NO ₃ ) (NH ₄ ) ₂ SO ₄ • 3 (NH) ₄ NO ₃ ) Nbs 674 ICDD Card: 40-660 ICDD Card: 47-0867 ICDD Card: None ² ICDD Card: 20-100 Hki 2θ Relative intensity hkI 2θ Relative intensity hkI 2θ Relative intensity hkI 2θ Relative intensity hkI ¹ 2θ Relative intensity 120 25.58 55.4 120 20.20 49 011 22.47 46 26.95 43 27.31 55 104 35.13 87.4 one hundred 20.47 one hundred 111 28.92 one hundred 27.18 one hundred 04/28 one hundred 113 43.36 one hundred 200 22.83 33 020 32.90 64 30.50 47 30.81 fifty 1) Card data is not indexed.
2) None of the existing map files exactly matched the experimental data.

Table II Intensity Parameters Ammonium sulfate Ammonium nitrate (NH ₄ ) ₂ SO ₄ • 2 (NH) ₄ NO ₃ ) (NH ₄ ) ₂ SO ₄ • 2 (NH) ₄ NO ₃ ) RIR Standard deviation RIR Standard deviation RIR Standard deviation RIR Standard deviation Variable cut Kα1 Peak Height 0.866 0.027 0.912 0.056 0.534 0.023 0.368 0.033 Kα1 Peak Area 0.717 0.010 0.737 0.051 0.503 0.009 0.401 0.021 Total peak area 0.724 0.006 0.714 0.050 0.508 0.008 0.381 0.027 Fixed cut Kα1 Peak Height 1.789 0.055 1.337 0.090 0.813 0.035 0.578 0.052 Kα1 Peak Area 1.481 0.021 1.090 0.075 0.767 0.013 0.630 0.033 Total peak area 1.497 0.013 1.057 0.740 0.773 0.013 0.599 0.042

The highest intensity peaks for several varieties could not

used for quantitative analysis, since there was a significant overlap between them. Use less intense diffraction peaks with little or no overlap and normalize based on relative peak heights. The intensities used in the above equation were average for the normalized intensities of the multiple peaks.

Quantitative analysis of diffraction data was collected using two scans. First sweep between 18 ° and 21 ° 2θ with 0.02 ° 2θ step sizes, 8 s / step. The second scan was collected from 30 ° to 34 ° 2θ with 0.02 ° 2θ step sizes, 8 s / step. The total data collection time was 48 min per sample and collected in two files per sample.

The first data file was collected between 18.2 ° and 21 ° 2θ and consisted of up to 6 peaks, depending on which phases were present. The second data file is collected in two intervals: from 30.4 ° to 31.8 ° 2θ and from 31.8 ° to 33.8 ° 2θ. Up to 4 peaks were found in the range from 30.4 ° to 31.8 ° 2θ, and up to 6 peaks were possible in the range from 31.8 ° to 33.8 ° 2θ. Figures 1, 2, and 3 illustrate diffraction scans and peaks for a sample prepared by mixing the (crude) 1: 2 and 1: 3 standards described above in equal proportions.

The collected results are entered into an EXCEL spreadsheet created for this analysis. Based on the relative peak area and FWHM, a spreadsheet determined whether an individual peak was suitable and whether a 1: 2 phase was present. Peaks in the region from about 30.5 ° to 30.8 ° 2θ at a low concentration, <5%, were difficult to correctly permissions and usually their FWHM becomes very large. Therefore, the mark for accepting these peaks is FWHM, which should be <0.25 ° 2θ. If the FWHM for a 1: 2 peak from about 30.5 ° was> 0.25, then the establishment of a 1: 3 peak at 30.8 ° becomes questionable and is flagged as invalid.

The spreadsheet then normalizes the peak intensities, averages the normalized intensities for each phase, and calculates the weight percent of each phase using Kα ₁ peak height, Kα ₁ peak area, total peak area and reports the average weight percent of these three calculations.

An example of such a process for the diffraction scans illustrated in Figures 1-3 is shown on the sheet with Table III. It can be seen that the sample studied by X-ray diffraction consists of 7.6 wt.% Ammonium sulfate, 42.4 wt.% Double salt 1: 2, 45.7 wt.% Double salt 1: 3 and 4.3 wt.% Ammonium nitrate.

The reproducibility of the XRD method was about ± 2%. However, compared with the material balances between the starting products and the products in the following examples, the XRD results were on average about 4.8 wt.% Slightly lower than the total ammonium sulfate in all compositions and 5.0% slightly higher than the total amount of ammonium nitrate. However, since material balance cannot provide information on the distribution of species present, the compositions of the compounds of the invention are defined in terms of XRD assays using the method described in detail above.

Measurement of crystallite size and its perfection (absence of defects) (CSP) was determined using the full half maximum width (FWHM) of the selected diffraction peaks corrected for the hardware expansion and Scherrer equation. The crystallite size for the 1: 2 double salt was obtained from the average number of CSPs from two peaks located at around 18.9 ° and 31.3 ° 2θ. The crystallite size for the 1: 3 double salt was obtained from the average number of CSPs from two peaks located in the region of about 13.6 ° and 30.8 ° 2θ. The CSP for ammonium sulfate was measured using a (111) peak at about 20.5 ° 2θ.

Analysis of the products by examples for water content was carried out using the Karl Fischer method.

Table III
Spreadsheet for quantitative XRD analysis Results Collected Normalization coefficient Normalized intensity Fit and range Phase Typical Peak Position Kα1 position Kα1 width Kα1 height Kα1 area total area Kα1 height Kα1 area total area Kα1 height Kα1 area total area Suitable (1-yes) (0 = no) 1st scan

18.2-20.9 3: 1 18.6 18.570 0.151 10467 1925 2567 0.26 0.31 0.31 37382 6210 8281 one 3: 1 + 2: 1 18.9 18.886 0.133 15685 2533 3628 0.1,0.38 0.09.42 0.09, 0.43 31439 4699 6702 one 3: 1 19.5 19.467 0.143 6136 1064 1532 0.16 0.16 0.15 38350 6650 10213 0 As 20.2 20.141 0.161 5353 1050 1499 0.45 0.64 0.64 11896 1641 2342 one As 20.5 20.416 0.133 8925 1447 2018 one one one 8925 1447 2018 one 2nd scan. 2: 1 30.5 30.417 0.178 15674 3392 3505 0.52 0.62 0.61 30142 5471 5746 1st fee 3: 1 308 30.750 0.130 18658 2937 4181 0.49 0.42 0.42 38078 6993 9955 one 30.2-31.8 2: 1 31.3 31.285 0.114 7222 997 1390 0.26 0.32 0.31 27777 3116 4484 one 2nd scan AN 320 32.796 0.161 4208 823 1-180 0.81 0.89 0.89 5195 925 1326 one 2nd charge 31.8-33.8

As 1: 2 1: 3 AN results Kα1 height Kα1 area total area Kα1 height Kα1 area total area Kα1 height Kα1 area total area Kα1 height Kα1 area total area RIR (Value) 0.866 0.717 0.724 0.367732 0.401 0.38096 0.534 0.503 0.508 0.912 0.737 0.714 Norm one 10410 1544 2180 29786 4428 5644 37730 6601 9118 5195 925 1326 % of the mass. 7.1% 7.8% 8.0% 47.8% 40.1% 39.4% 41.7% 47.6% 47.7% 3.4% 4.5% 4.9% Wed value 7.6% 42.4% 45.7% 4.3%

The following examples are presented to demonstrate a more complete understanding of the present invention. Specific techniques, conditions, materials, ratios and reported data are presented to illustrate the principles of the invention as exemplary, and should not be construed as limiting the scope of the invention.

EXAMPLES

Comparative Example 1

Ammonium sulfate granules of an average size of about 1 mm were obtained from Honeywell International. Ammonium sulfate consisted of 98 wt.% (NH ₄ ) ₂ SO ₄ and contained less than 0.2 wt.% Organic impurities. Forty pounds (1 pound = 453.6 g) of this product is milled in a ball mill at Union Process Company, Akron Ohio. At the completion of grinding in a ball mill, ammonium sulfate was sieved to remove basically all particles that do not pass through the Tyier No. sieve 48. The basic and sieved ammonium sulfate contained approximately 0.2 wt.% Water.

Ammonium nitrate manufactured by Air Products and sold under the registered brand name "Ammo Nite®" had a content of 97 wt.% NH ₄ NO ₃ and contained 1.7 wt.% Water.

Ammonium sulfate and solid particles of ammonium nitrate were mixed in a small pyrex beaker in equal molar ratios. The total weight of the loaded substances was 10 g. The beaker was placed in a thermostat at a temperature of 200 ° C until ammonium nitrate melted. Then it is removed from the thermostat for a moment, thoroughly mixed and immediately returned to the thermostat for 30 minutes. Once ammonium nitrate has been melted, at least a portion of the ammonium sulfate has dissolved and reacted with ammonium nitrate.

The glass is removed from the thermostat and allowed to cool on the laboratory bench. Then the glass is opened and the product in the form of a hard disk is removed. Part of the specified product in the form of a disk is broken off and ground to a particle size of -40 μm to remove X-ray diffraction. Several large fragments were analyzed for their water content by the Karl Fischer method.

The composition of the product determined by XRD and Karl Fischer assays is shown below in Table IV. The source of water in the product was in solid particles of ammonium sulfate and ammonium nitrate. Water was not added at loading.

Example 2

The same ammonium sulfate and ammonium nitrate, as described in comparative example 1, were mixed in equal molar ratios. As in comparative example 1, the charge of ammonium sulfate and ammonium nitrate is 10 g. However, in this example of the invention, water was added to the solid particles in the beaker. The water content was 5.45 wt.% Of the total load.

The experiment procedure in this example was identical to the procedure of the specified comparative example 1, with the exception of adding water to the load and placing the thermocouple in a beaker that was left in a thermostat to measure the cooling rate. It was found that the cooling rate during solidification of the charge was about 100 ° C / min. The composition of the product determined by XRD and Karl Fischer assays is shown below in Table IV.

Table IV  wt.%, (water-free base) Example or compound according to example Ammonium sulfate (NH ₄ ) ₂ SO ₄ • 2 (NH) ₄ NO ₃ ) (NH ₄ ) ₂ SO ₄ • 2 (NH) ₄ NO ₃ ) Ammonium nitrate Water% wt. 1 (Connection) 36 one 52 eleven 0.34 2 24 69 7 0 0.55

It was noted that the introduction of 5.45 wt.% Water into an equimolar mixture of ammonium sulfate - ammonium nitrate had a huge effect on the composition of the product. Water has shifted the balance between a 1: 3 double salt and a 1: 2 double salt to virtually eliminate the formation in favor of the latter. The remainder of ammonium nitrate was also markedly reduced.

Examples of the invention and comparative examples 3-36

A series of samples of ammonium nitrate sulfate was obtained using the same ammonium sulfate and ammonium nitrate described in comparative example 1. The parameters that were varied to obtain a series of samples were the temperature in the thermostat, the molar ratio of ammonium sulfate to ammonium nitrate and the percentage of water weight in loading. The size of the load was 10-55 g. The procedure used was different from that described in comparative example 1.

Table V shows the temperature of the thermostat, the molar ratios of the loaded ammonium sulfate (AS) and ammonium nitrate (AN), the amount of water in mass percent and the composition of the products. Water loading data, including absorbed water in ammonium sulphate and ammonium nitrate and any liquid water additionally added.

The product data of Tables IV and V are plotted in FIGS. 4-6 in comparison with the percent by weight percent. water in loading. Figure 4 shows that when the amount of water in the charge rises from about 1 wt.% To 2.3 wt.%, The proportion of the double salt 1: 2 increases from about 10 wt.% To more than 60 wt.% Of the product. Further, when the amount of water in the charge exceeded about 2 wt.%, The proportion of the double salt 1: 3 and the residual amount of ammonium nitrate sharply decreased to percent in fractions of units or to zero.

The data of Tables IV and V can also be used to compare% wt. water in educated products. 7 shows that changes in product compositions occur with one exception, when the residual water in the product immediately after the formation of the product exceeded about 0.4 wt.%

Table v Example or compound Example No. Molar ratio AS / AN loading  wt.% water loading  wt.% in the product according to XRD (water - free base)  wt.% water in the product As (NH ₄ ) ₂ SO ₄ • 2 (NH) ₄ NO ₃ ) (NH ₄ ) ₂ SO ₄ • 3 (NH) ₄ NO ₃ ) AN T = 180 ° C 3 1001 6.93 eighteen 82 0 0 0.74 four 1,000 5.45 25 75 0 0 0.62 5 1,000 9.72 24 76 0 0 0.53 6 1.002 9.72 23 77 0 0 0.48 7 1.002 9.72 23 77 0 0 0.48 T = 190 ° C 8 (comp.) 1,000 0.76 33 fourteen 53 0 0.07 9 (comp.) 1,000 0.76 34 eleven 55 0 0.03 10 1,000 5.45 23 77 0 0 0.49 eleven 1,000 9.72 25 75 0 0 0.50 T = 200 ° C 12 1.001 6.30 34 62 four 0 0.51 13 (comp.) 1.002 1.73 33 0 58 9 0.31 fourteen 1.002 9.72 twenty 80 0 0 0.72 15 (comp.) 0.944 0.78 35 one 48 eighteen 0.12 16 (comp.) 1.079 0.73 37 3 46 fifteen 0.03 17 0.944 5.37 fourteen 83 3 0 0.49 eighteen 1.079 5.55 19 81 0 0 0.62 19 0.944 9.55 17 80 3 0 0.59 twenty 1.079 9.92 23 77 0 0 055

Table V (Continued) Example or compound Example No. Molar ratio AS / AN loading  wt.% water loading  wt.% in the product according to XRD (water - free base)   wt.% water in the product As (NH ₄ ) ₂ SO ₄ • 2 (NH) ₄ NO ₃ ) (NH ₄ ) ₂ SO ₄ • 3 (NH) ₄ NO ₃ ) AN 21 1.002 7.91 24 76 0 0 0.64 22 (comp.) 1.414 0.65 46 0 82 eighteen 0.09 23 (comp.) 0.909 0.79 34 2 58 9 0.08 24 (comp.) 0.606 0.94 23 one 60 16 0.10 25 (comp.) 0.404 1.09 17 2 55 26 0.26 26 (comp.) 0.260 1.23 10 2 49 40 0.27 27 (comp.) 1,000 0.76 33 9 58 0 0.07 28 (comp.) 1,000 0.76 33 8 60 0 0.08 29th 1,000 5.45 23 77 0 0 0.56 thirty 1,000 9.72 21 79 0 0 0.48 31 (comp.) 0.999 1.34 25 43 32 0 0.37 32 (comp.) 0.999 2.34 22 65 13 0.3 0.60 33 0999 3.32 23 72 5 0 0.59 34 0.999 4.23 25 72 3 0 0.7 35 0.999 5.22 24 77 0 0 0.73 36 0.999 6.15 26 71 3 0 0.71

The density of the products in comparative examples 8-9, 27-28 and examples 10-11, 29-30 were determined as follows. After the glasses containing the products were cooled, they were broken and the products were isolated in the form of short cylinders. The base and sides were very smooth, but the top required manual grinding with silicone carbide paper to ensure a uniform, flat surface. Densities were then determined based on measurements of the dimensions and weights of the cylinders. The density of the product increased with increasing water content, as shown in Table VI.

Table VI Example or comparative example No. The reaction temperature, ° C The density of the product, g / cm ³  wt.% water in the product 8 (comp.) 190 1.27 0.07 9 (comp.) 190 1.24 0.03 10 190 1.46 0.49 eleven 190 1.50 0.50 27 (comp.) 200 1.40 0.07 28 (comp.) 200 1.33 0.08 29th 200 1.45 0.56 thirty 200 1.47 0.48

The multiple effects of water on the composition of the product and density, given as data from Tables IV-VI and FIGS. 3-7, are surprising and unforeseen from the prior art.

Examples 37-38

Two ammonium nitrate sulfate products were obtained, the crystallite size of ammonium sulfate and the dispersion uniformity among the double salt crystals were determined. Two batches were prepared, each consisting of 31.15 g of ammonium sulfate, a purity reagent (Fisher Scientific), 18.85 g of ammonium nitrate without brand name and 5.0 g of water. The molar ratio of ammonium sulfate to ammonium nitrate was 1.001: 1. Ammonium sulfate was pulverized to fine particles passing through a Tyler No. sieve. 230 (hole 270 μm). Ammonium nitrate was crushed from small granules in a mortar and pestle.

The batches were mixed in small glasses and placed in a thermostat at a temperature of 180 ° C. After the charge was melted, the glasses were taken from the thermostat, mixed and returned to the thermostat. One charge was removed, mixed and returned to the thermostat several times over the next 30 minutes. The other charge remained untouched in the thermostat for these 30 minutes after initial mixing. At the end of this period, the glasses were removed from the thermostat and cooled at room temperature.

XRD analysis of the products showed identical phase compositions: 23 wt.% Ammonium sulfate, 77 wt.% Double salt 1: 2 and the absence of a double salt 1: 3 or residual ammonium nitrate. The residual water was 0.48 wt.%. The crystallite size and (CRP) were measured for each sample using the previously described X-ray. Assuming that the x-ray expansion of the peak is completely dependent on the crystallite size, an estimate was obtained of the lower limit of crystallite size. The results are shown in Table VI.

Table VII Example No. Mixing condition Crystallite size, micrometers Ammonium sulfate (NH ₄ ) ₂ SO ₄ • 2 (NH) ₄ NO ₃ ) 37 once > 8 0.18 38 often 0.35 0.37

The crystallite sizes, as determined by XRD, of both ammonium sulfide and 1: 2 double salt phases were less than about 1 μm for a well-mixed system, showing the optimal closeness of ammonium sulfate to the 1: 2 double salt. However, microscopic examination revealed a certain amount of ammonium sulfate crystals having dimensions of about 35 μm in a frequently mixed sample. These may be undissolved residues of ammonium sulfate particles (size -270 μm) in the initial loading.

Samples were also examined using an energy dispersive spectrometer attached to a scanning electron microscope to detect sulfur at magnification and values having a resolution of about 2 microns. No separation of ammonium sulfate was found at this scale, except for the particles noted above. The dispersion of ammonium sulfate in the double salt phase 1: 2 was in degree higher than 2 microns of the resolution of the increase and the values used. Such a high degree of dispersion is very beneficial in terms of ammonium sulfate acting as an inhibitor in detonation.

Example 39

High Speed Calorimetry (ARC) experiments were conducted by an independent laboratory using samples from Honeywell International Inc. The ARC method makes it possible to expose the sample to a precisely defined amount of heat while a self-accelerating reaction is identified. A specifically used method was the Open ARC method, in which a thermocouple was placed directly in a sample in an open vessel. This method is used for high-energy reaction systems that cannot be contained in a closed vessel and are designed to provide consistent interpretation of thermal hazards. Several test samples consisted of:

- ammonium nitrate sulfate according to the invention, obtained from an equimolar mixture of ammonium sulfate and ammonium nitrate;

- a double salt of 1: 3 containing about 1-2 wt.% ammonium sulfate and about 3 wt.% ammonium nitrate;

- ammonium nitrate.

Initial temperatures for spontaneous and energy decomposition are shown in Table VIII.

Table VIII Compound Initial ° C temperature., ammonium sulfate 220-236 double salt 1: 3 211 ammonium nitrate 205-210

It is noted that the ammonium nitrate sulfate according to the invention was more stable (higher initial temperature) or than a double salt of 1: 3, or ammonium nitrate.

Example 40

Tests are carried out in accordance with the United Nations Recommendations on the Transport of Dangerous Goods, "" Manual of Tests and Criteria, 1995 "," Section 34, Classification Procedures, Test Methods and Criteria Relating to Oxidizing Substances of Division 5.1. "" The test method is designed to measure potential solid substance to increase the burning rate or burning rate of a combustible substance when the two components of the combustion process are completely mixed. "

The substance to be tested is mixed with cellulose in the proportions 4: 1 and 1: 1, formed into a conical stack with specific dimensions, which is heated from below using electricity (red heat) passing through a nichrome wire. A substance is not considered to be an oxidizing agent if, in both 4: 1 and 1: 1 ratios, the sample / cellulose does not ignite and does not burn for three minutes or if it shows an average burning time longer than that of a 3: 7 mixture of potassium bromate and cellulose. Samples tested:

1. A control consisting of 9 g of potassium bromate + 21 g of cellulose. Potassium bromate was sieved so that the particle size was between 0.15 mm and 0.3 mm.

2. 15 g of ammonium nitrate sulfate according to the invention + 15 g of cellulose. Ammonium nitrate sulfate was sieved so that the particle size was between 1.70 mm and 3.55 mm. This composition includes 23 wt.% Ammonium sulfate, 77 wt.% Double salt 1: 2 and double salt 1: 3 ammonium nitrate.

3. 24 g of ammonium nitrate sulfate according to the invention, as described above + 6 g of cellulose.

4. Only cellulose.

5.15 g of ammonium nitrate + 15 g of cellulose. Ammonium nitrate particles were sieved through a Tyler No. sieve. 10 (+1.70 mm). The test results are shown in Table IX.

Table IX Sample Ignition time, sec. Burning time, sec. 3: 7 (w / w) QurO ₃ : cellulose 10 128 1: 1 (w / w) ammonium sulfate nitrate: cellulose no ignition> 3 min. -

4: 1 (w / w) ammonium sulfate nitrate: cellulose no ignition> 3 min. - cellulose no ignition> 3 min - 1: 1 ammonium nitrate: cellulose 60 93

Tests have shown the ammonium sulfate nitrate of the invention is not an oxidizing agent.

Example 41

The moisture sensitivity of ammonium nitrate sulfate according to the invention is determined in comparison with ammonium sulfate and ammonium nitrate by measuring the levels of "Critical Moisture". Critical moisture is that relative humidity (R.H) at which, at a given temperature, the product begins to absorb moisture from the atmosphere. Tests are carried out using the IFDC method C 101, as described in "Manual For Determining Physical Properties of Fertilizer", 2 Ed., 1993, International Fertilizer Development Center located in Muscle Shoals, Al.

The test ammonium sulfate was crushed and sieved, as described in comparative example 1. Ammonium nitrate was a reagent of purity Fisher Scientific. Ammonium nitrate sulfate according to the invention was composed of 23 wt.% Ammonium sulfate, 77 wt.% Double salt 1: 2 and did not contain essentially a double salt 1: 3 or ammonium nitrate.

The critical moisture levels measured at a temperature of 30 ° C were as follows:

Ammonium Sulphate - 80% R.H.

Ammonium nitrate sulfate according to the invention is 75% R.H.

Ammonium Nitrate - 60% R.H.

It is noted that the ammonium nitrate sulfate of the invention was much less sensitive to moisture than ammonium nitrate and similarly in this respect than ammonium sulfate.

Claims (22)

1. Ammonium nitrate sulfate, containing according to x-ray diffraction: from 14 to 35 wt.% ammonium sulfate ((NH ₄ ) ₂ SO ₄ ); from 60 to 85 wt.% (NH ₄ ) ₂ SO ₄ · 2 (NH ₄ NO ₃ ) double salt and up to 5 wt.% in the amount of (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) double salt and ammonium nitrate (NH ₄ NO ₃ ). 2. Ammonium nitrate sulfate according to claim 1, characterized in that (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) a double salt and ammonium nitrate (NH ₄ NO ₃ ) in total amount to 3 wt.%. 3. Sulfate ammonium nitrate according to claim 1, characterized in that the ammonium nitrate (NH ₄ NO ₃ ) is up to 1 wt.%. 4. Sulfate ammonium nitrate according to claim 1 in the form of granules. 5. Ammonium nitrate sulfate, containing according to x-ray diffraction: from 14 to 35 wt.% ammonium sulfate ((NH ₄ ) ₂ SO ₄ ); from 60 to 85 wt.% (NH ₄ ) ₂ SO ₄ · 2 (NH ₄ NO ₃ ) double salt and from 0 to 5 wt.% in the amount of (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) double salts and ammonium nitrate (NH ₄ NO ₃ ). 6. Ammonium nitrate sulfate according to claim 5, characterized in that it contains (NH ₄ ) ₂ SO ₄ · 3 (NH ₄ NO ₃ ) double salt and ammonium nitrate (NH ₄ NO ₃ ) in the amount of up to 3 wt.%. 7. Sulfate ammonium nitrate according to claim 5, characterized in that the ammonium nitrate (NH ₄ NO ₃ ) is up to 1 wt.%. 8. Sulfate ammonium nitrate according to claim 5 in the form of granules. 9. A method of producing ammonium nitrate sulfate, comprising the steps of: (a) loading substances containing particles of ammonium sulfate and ammonium nitrate and water into a melting device, wherein the molar ratio of ammonium sulfate to ammonium nitrate is from 0.9: 1 to 1.1: 1 and water is more than 2 up to 10 wt.% of the load; (b) melting ammonium nitrate and dissolving at least a portion of the particles of ammonium sulfate at a temperature of from 180 to 210 ° C; (c) the interaction of the loaded products at a temperature of from 180 to 210 ° C; and (d) solidification of the product at a cooling rate above 100 ° C / min. 10. The method according to claim 9, characterized in that the ammonium sulfate and ammonium nitrate have a degree of purity above 90 wt.%. 11. The method according to claim 9, characterized in that the ammonium sulfate and ammonium nitrate have a degree of purity above 95 wt.%. 12. The method according to claim 9, characterized in that the ammonium sulfate and ammonium nitrate have a degree of purity above 97 wt.%. 13. The method according to claim 9, characterized in that over 85% of the ammonium sulfate particles pass through a sieve with an opening of 0.030 mm. 14. The method according to claim 9, characterized in that more than 99 wt.% Particles of ammonium sulfate pass through a sieve with an opening of 0.030 mm. 15. The method according to claim 9, characterized in that more than 99 wt.% Particles of ammonium sulfate pass through a sieve with an opening of 0.030 mm and more than 50 wt.% Pass with an opening of 0.074 mm. 16. The method according to claim 9, characterized in that the melting point and the reaction of interaction have values from 190 to 205 ° C. 17. The method according to claim 9, characterized in that the melting point and the reaction of interaction have values from 190 to 200 ° C. 18. The method according to claim 9, characterized in that the water is from 2 to 5 wt.% From the load. 19. The method according to claim 9, characterized in that the water is from 2.5 to 4 wt.% From the load. 20. The method according to claim 9, characterized in that it is carried out as a continuous process. 21. The method according to claim 9, characterized in that the solidification of the product is carried out in a prilling column. 22. Ammonium nitrate sulfate obtained by a process comprising the steps of: (a) loading substances consisting of particles of ammonium sulfate and ammonium nitrate and water into a melting device, wherein the molar ratio of ammonium sulfate to ammonium nitrate is from 0.9: 1 to 1.1: 1 and water is from 2 to 10 wt.% of the load; (b) melting ammonium nitrate and dissolving at least a portion of the particles of ammonium sulfate at a temperature of from 180 to 210 ° C; (c) the interaction of the loaded products at a temperature of from 180 to 210 ° C; and (d) solidification of the product at a cooling rate of more than 100 ° C / min.

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