SU1057415A1 - Method for preparing diammonium phosphate - Google Patents

Abstract

1. METHOD OF OBTAINING. DIAMMONIUM Phosphate, which includes treating phosphoric acid with gaseous ammonia to a pH of 8.05-8.15 at elevated temperature, crystallizing at 20-40 seconds and separating the product, so that, in order to simplify process by eliminating drying, reducing the time of the process and reducing the caking of the product while ensuring its high frequency, crystalline diammonium phosphate is introduced into the solution at the ammonia treatment stage at pH 6.1-6.2 and the subsequent treatment with ammonia is carried out at a rate of 0.4- 0.6 g / min 5. A method according to claim 17, characterized in that the diammonium phosphate is taken in an amount of 0.5- Q 9 1.5 wt.%.

Description

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The invention of the law: ;; ti; h k s; io (;: OOz of obtaining phostsri, sopi Part of the diamopicphosphate reactive qualification; .and used in any case. Farcerized chemical :: suit nr., iiJ.neiif-ocTH,

There is a method of populating crystalline diam- nolyphosphate from its solution in the presence of BOTsOsoluble 1-st sulfates and chlorides, added in an amount of 3-5%, the method produces a large amount; -100mlichbsky diam; with hydrogen phosphate with pulp; O, crystal crystals, 5-2.5 mm 1.

The disadvantage of this method is the presence in the product of a mixture of glorification and sulfate ions; In addition, it is not difficult to produce a reactive qualification product.

The closest to the proposed by the technical essence to the achievement of the ei-oMy test is a method of obtaining dsg lg-yunkyfaty h:; l; its Kli from the city; s. rachnor for 2, 5–3 ,, 8 hours nps-i 8 O-85 C to pH-8., 05 8, 1 5, crista-lehsupiyu at 2Q-10 ° C:. 2.7-6.2 h, detachment jiOo.-iyj {Ta center-icyi-HpoEai-nieiy

qualif-ixaL AI i ;.; arch, h,;; The content of ocLiuyioro nationality is equal to 49.2%, the pK of 5% -staor eO-8; 1,

Not, the state of the first 1 star; ogch ,. 1-s required way: -; -, stationiu SuI,;: -; humid:, oh phototect due to t:,: -; sunth-r impurity TpHa; v; f.- cfia; ; apo, and obtaining a product from the form of chalk; Crista, l, g: ov .. the size of which is ke pre-. melts Oh 4 j-iji

Purpose isobrebgP-); - simplified ;; process efg: 0-; yeni drying., reduction

; reversing the process and reducing the caking of the product while ensuring its high purity.

This goal is achieved by the fact that c; according to the method of obtaining dia: mmonium phosphate, cc:, ultimately, the treatment of phosphoric acid with a high temperature of gaseous gases of 1 mio. RQ pH 8f05--8.15 Crystallization at 20–40 ° C and product separation, while the solution at the stage of treatment with ammonia at pH 6.1–6.2 is injected crystalline digimonium phosphate and poJ, the final treatment a, g with 1 m Oh, 6 g / m and.

In addition to rorOf diammonium phosphate, I also take an amount of 0 ,, 5-1, -5 wt.% O

PR and L5 e p 1. 370 g of thermally phosphoric acid of reactive qualification with a concentration of 50% (p 1.335 g / cm) is placed in a reactor with an iJOO ml capacity and aki-donated gas 4 at 80 ° C with a scaled g / min: When a pH of 1 reaches 6D5 in an ammoniated solution of diammoxyphosphate (1% of 2 kO is added, the quantity of the final product / moisture is 5% and amg, the ionization is continued at a rate of 0.5 g / min to a pH of 8.1, 1 d; , The temperature is not higher, then the pulp is cooled at 3 hours. The mixture is centrifuged. The mixture contains 99.36% vioro bases, and is in accordance with brand x „H. The average size of the crystal is usB, dia: - / uniphosphate 0.88 mm.

Example 2 The process is carried out as described in Pr-1er. The difference is in changing the pH of the solution Ea. which is used to add, diammonium phosphate,

Table 1 shows the dependence of 1:) the size of crystals and the content of axial vein; 1, in the final product, on the pH of the solution,

Table 1

fishing to about, 8 NiM and get a product of reactive qualification, corresponding to the brand k, h. (content of the main substance 99.25-99.36 / pH of a 5% solution of 8.15-8.18). The introduction of crystalline diammonium phosphate at a pH of less than 6.1 leads to a decrease in the size of the crystals and a deterioration in the quality of the product due to the presence of a triammonium phosphate impurity in it, which increases the content of the basic substance and the pH of the 5% solution. When the pH of the solution is more than 6.2, the product is of high quality but finely crystalline.

From the data given in table. 2, it follows that carrying out the process of producing diammonium phosphate without isolating the additive leads to the formation of a crystalline product contaminated with an admixture of triammonium phosphate.

The introduction of crystalline diammonium at the ammonization stage (1 Kesfate in an amount of 0 to 5–1.5% by weight ensures high purity of the product and the required size of crystals. The addition of crystalline diammonium phosphate in an amount of more or less 0.5 to 1.5% by weight is not appropriate.

as this leads to the formation of a crystalline product.

Example 4. The process is carried out as described in Example 1. The difference is in changing

ammonization rate since the introduction of crystalline diammonium phosphate.

B-tab. Figure 3 shows the dependence of the size of the crystals and the content of the basic substance in the finished product on the rate of ammonization.

Table Example 3. The process is carried out as described in example 1, the difference lies in the amount of crystalline diagfunium phosphate introduced from the ammonization stage. In tab. Figure 2 shows the dependence of the size of the crystals and the content of the main substance in the finished product on the amount of diammonium phosphate applied. Table2 From table. 3, it follows that the optimal rate of amgonization since the introduction of crystalline diamg-uniphosphate is a rate of 0.40, 6 g / min, ensuring the production of a large-crystalline product of high purity. With the introduction of agfuniiation process with a speed exceeding 0.6 g / min, the finished product as a result of local intersections contains

We offer

Prototype

93-113

Baseline From Table 4, it follows that, in conjunction with the known ones, the proposed method for the production of reactive carbon dioxide diammonium phosphate makes it possible to obtain a large-crystalline product while ensuring high quality. This simplifies the techno99, 188,12

99.048, -11

44. 24

99,238,14

99.258,15

99,268.15

40,54

195

99,366.18 38.10

T a

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8.18

0.76-0,, 88 8.1 0.3-0.4 8, 9 O, 3-0, 6 30

Table

The finished product is tracked.

The finished product is tracked.

Also

The same 200 is applied; it is a trimonium monophosphate, as a result of which, according to the content of the basic substance and the pH of a 5% solution, it does not possess the necessary purity. Maintaining an ag rate in toning of less than 0.4 g / min is associated with an increase in: the duration of the process. Table 4 shows the diammonium phosphate indicators obtained from lime and and by the proposed methods. its production due to the exclusion of the drying stage. The effect of the size of diammo: iphosphate crystals on the technological parameters of the process is given in Table 5.

From the data given in table. 5 it follows that with an increase in the size of the crystals of diammonium diphate, the loss of the useful component decreases, as evidenced by the content of the basic substance in the mother liquor. At the same time, the yield of the finished product is increased by 10%. Changing the size of the diammonium diphate crystals affects the filtration rate, which reduces the time it takes to separate the crystals of the product. An increase in the size of the crystals favorably affects the improvement of the physicochemical properties of the product, in particular its tracking. Thus, diammonium phytophate crystals of size 1, above 0.65 mm, are not followed by storage.

The implementation of the proposed method for the preparation of diammonium diphate allows to simplify the process of deactivating the elimination of the drying stage, shorten the process time as a result of accelerating the sedimentation phase, to obtain a product that meets the qualifications of chemically pure. and non-caking during storage.

Claims (1)

1. METHOD FOR PRODUCING. DIAMO- NIIFOSFATA, including the treatment of phosphoric acid with gaseous ammonia to a pH of 8.05–8.15 at elevated temperature, crystallization at 20–40 ° C and separation of the product, distinguished by the fact that, with In order to simplify the process by eliminating drying, reducing the process time and reducing the caking of the product while ensuring its high frequency, crystalline diammonium phosphate is introduced into the solution at the stage of processing with ammonia at a pH of 6.1–6.2 and subsequent treatment with ammonia is carried out with 0.4-0.6 g / min. H. The method according to claim 1, characterized in that the di-ammonium phosphate is taken in an amount of 0.51.5 wt.%.