Method of production of monopotassium phosphate

FIELD: medicine and microbiology; agriculture and food industry; methods of production of monopotassium phosphate.

SUBSTANCE: the invention is pertaining to production of monopotassium phosphate used as fertilizers, food additives, and also in medicine and microbiology. The method provides for neutralization of phosphoric acid by potassium carbonate up to pH not above 4.5 at the heightened temperature, separation of the produced admixture by filtration with the subsequent crystallization and separation of the finished product at cooling. Potassium carbonate take in the form of a water solution with the concentration necessary for production in the neutralized mixture of 23-30 % monopotassium phosphate. The neutralization process is conducted at the temperature of 70-78°C, and the mother liquor after separation of the finished product at the stage of a crystallization return into the process on the stage of dissolution of potassium carbonate. Reaction of the neutralization conduct up to pH = 3.8-4.5. The technical result is an increase of output of the finished product up to 95-97 % and creation of the wasteless production due to utilization of a mother liquor in the process.

EFFECT: the invention ensures increased output of the finished product up to 95-97 %, creation of the wasteless production due to utilization of a mother liquor in the process.

2 cl, 3 ex

 

The invention relates to a method for monokaliy used as fertilizer, food additives, as well as in medicine and Microbiology.

A method of obtaining one-deputizing phosphates of alkali metals or ammonium (in our case the monokaliy), including the processing of phosphoric acid compound potassium at high temperatures with subsequent crystallization of the product. This method of thermal phosphoric acid (judging by the content of impurities contained in the description) is treated with 45%potassium hydroxide solution. The temperature of the reaction mixture 90-95°C, the pH of the mixture of 5.85 to 6.0. Then hold crystallization from a saturated solution at 80-85°at pH of 5.8-6.0. Next, the product is dried for 24 hours of the Product is obtained as white crystals (ed. St. USSR №1782935, 01 25/30, BI, No. 47, 1992).

The disadvantages of this method are the large loss of product due to the high crystallization temperature, since at this temperature the potassium phosphate has a sufficiently high solubility. The use of expensive components - thermal phosphoric acid, potassium hydroxide.

The closest to describing the technical essence and the achieved result is a method of obtaining monokaliy, including the neutralization of phosphoric acid with potassium carbonate to pH the e higher than 4.5 at elevated temperature, separation of the resulting mixture by filtration, followed by crystallization and separation of the finished product when cooled (Patent RF №2164494, 01 25/30, 2001).

According to this method, use the dry potassium carbonate, which is metered in wet-process phosphoric acid (EPA). The neutralization reaction is conducted at temperatures 80-89°With up to pH 3.5-4.5. In these circumstances, the neutralized mixture is formed monokaliy in the number of 45-48%, and the sediment fall insoluble orthophosphate, iron, aluminium, fluoride of calcium, magnesium and other compounds. With impurities seacadets also part monokaliy. The resulting mixture is separated on a filter at a temperature of 70-80°C. the Filtered solution is cooled to a temperature of 15-20°C. the Precipitated crystals of the pure product is separated and dried, and the mother liquor after the cooling phase is withdrawn from the process. The yield of pure product is 60-65%.

The disadvantage of this method is primarily not a high yield of pure product, great loss monokaliy at the stage of separation of impurities and the presence of wastewater in the form of mother solutions after the cooling phase.

We were set a task to increase the yield of the finished product and create a virtually waste-free production.

The problem is solved in the proposed method of obtaining monokaliy, enabling the m neutralization of phosphoric acid with potassium carbonate to a pH of not higher than 4.5 at elevated temperature, separation of the resulting mixture by filtration, followed by crystallization and separation of the finished product when cooled. In this way the take potassium carbonate in aqueous solution with the concentration needed to obtain the neutralized mixture 23-30% monokaliy, the neutralization process is conducted at temperatures 70-78°at pH 3.8 to 4.5, and the mother liquor after separation of the finished product at the stage of crystallization return in the process at the stage of dissolution of potassium carbonate.

To obtain pure monokaliy and reduce its losses at the stage of neutralization is necessary to avoid cocrystallization impurities together with monokaliy, so in the process of neutralization find the concentration of an aqueous solution of potassium carbonate, the reaction temperature. The determining factor is the concentration of monokaliy in the neutralized solution. When the stated concentration is not cocrystallization impurities with monokaliy. Impurities are deposited on the filter at a temperature 60-69°C. From the temperature of the neutralization process depends on the solubility of the impurities. They remain in the solution and then crystallize with the finished product. In the proposed process maximum impurities are deposited on the filter, so the filtrate is clean, the whole monokaliy in solution and, therefore, after crystalliza the AI significantly increased output of finished product. The PH at the stage of neutralization may not be lower than the 3.8, so as not maintained the required content2O in the finished product.

Using the proposed method allows to increase the output of the finished product with 60-65% (the prototype) to 95-97%. Furthermore, the mother liquor obtained after the stage of crystallization, is returned to the process. The amount of sludge remaining on the filter depends on the amount of phosphoric acid and less than 5% by weight of the finished product, therefore, besides the solid residue, waste production no.

The method is illustrated by the following examples.

Example 1. In the reactor load 2,5 t solution2CO3with a concentration of 20% To2CO3and 1290 kg solution orthophosphate acid with a concentration of 55% H3PO4. The neutralization reaction is conducted under stirring until pH 3.8, at a temperature of 70°C. the resulting solution montalivet with mass fraction of 27% KN2PO4and precipitate insoluble impurities (FePO (4, AlPO4, KF, K2SiF6) in the amount of 3.1 kg, which is separated in the filter at a temperature of 60°C. Next, clean the solution monokaliy evaporated to a mass fraction of 40% KN2PO4, cooled to a temperature of 20°C. the Precipitated crystals are separated and dried. It turns out 650 kg monokaliy and 1800 kg mother liquor containing 18,5 KN 2PO4, which additionally produce 300 kg monokaliy. The total yield of product will be 96,4%.

Example 2. In the reactor load 1800 kg stock solution with a concentration of 18.5% KN2PO4, 338 kg of potash and 350 kg of water. The resulting solution was neutralized 960 kg of orthophosphoric acid with a concentration of 50% H3PO4. The reaction temperature 75°C, pH of 4.1. The resulting solution monokaliy with a mass fraction of 30% KN2PO4and precipitate insoluble impurities in the amount of 2.8 kg, which is separated in the filter at a temperature of 65°C. Next, clean the solution monokaliy evaporated to a mass fraction of 40% KN2PO4, cooled to a temperature of 20°C. the Precipitated crystals are separated and dried. The mother liquor returned to the stage of preparation of a solution of potash. Got a 650 kg monokaliy, 1830 kg mother liquor containing 18% KH2PO4. The total yield of the product was 97,0%.

Example 3. In the reactor load 2.5 tons of solution K2CO3with a concentration of 16% K2CO3and 1034,5 kg of a solution of phosphoric acid with a concentration of 55% H3PO4. The process is conducted under stirring, the temperature is 78°C and pH 4.5. This forms a solution montalivet with mass fraction 23% KN2PO4and sediment 4.8 kg, which is separated in the filter at a temperature of 69°C. Further pure RA is creative monokaliy evaporated to a mass fraction of 40% KH 2PO4cool, the precipitated crystals are separated and dried. It turns out 550 kg monokaliy and 1400 kg mother liquor containing 17% KN2PO4. The total product yield is 95%.

1. The method of obtaining monokaliy, including the neutralization of phosphoric acid with potassium carbonate to a pH of not higher than 4.5 at elevated temperature, separating the mixture by filtration, followed by crystallization and separation of the finished product when cooled, characterized in that the take potassium carbonate in aqueous solution with the concentration needed to obtain the neutralized mixture 23-30% monokaliy, the neutralization process is conducted at temperatures 70-78°and the mother liquor after separation of the finished product at the stage of crystallization return in the process at the stage of dissolution of potassium carbonate.

2. The method according to claim 1, characterized in that the stage of neutralization lead to pH=3.8 to 4.5.



 

Same patents:

FIELD: agriculture; production of mineral fertilizers.

SUBSTANCE: the invention is pertaining to production of ammonium phosphates, in particular, diammonium phosphate widely used in agriculture as mineral fertilizers. The method includes neutralization of phosphoric acid by ammonia at an increased pressure, a stirring action of the produced mixture in a static mixer with its subsequent granulation and drying of the product. Neutralization is conducted in two stages: on the first of which feed 8 - 85 % of ammonia from total amount and the process is conducted under the pressure of 3.5 - 8.0 atm, and on the second stage feed the remained amount of ammonia and reduce pressure to 1.5 - 3.0 atm. At that the stirring action is carried on simultaneously with a treatment of the mixture with ultrasound with a pulse power from 100 up to 1000 W. Before granulation additionally reduce the pressure by 0.5 - 0.8 atm as compared with the pressure of the second stage of neutralization. Ultrasonic treatment additionally conduct and on the first stage of neutralization. The technical result is production of a homogenous product of improved quality, decreased power inputs and losses of ammonia in the general process.

EFFECT: the invention ensures production of a homogenous product of improved quality, decreased power inputs and losses of ammonia in the general process.

2 cl, 3 ex

FIELD: fertilizers, chemical technology.

SUBSTANCE: invention relates to a method for preparing monoammonium phosphate used broadly as a mineral fertilizer. Method involves decomposition of phosphate with a mixture of phosphoric and sulfuric acid, separation of reaction mass with isolation of the production acid, its purifying from impurities, concentrating, ammoniation to obtain phosphate pulp and the following procedures of granulation and drying. The separated production acid is concentrated and then subjected for purification from impurities and ammoniated maintaining the content of P2O5 in the concentrated acid at these stages in the range 52-56%, the content of SO3 at the range 1.5-3.2%, the residual content of solid impurities in the cleared concentrated acid 0.2-0.6% by mass, and the mole ratio NH3 : H3PO4 in the range 1.01-1.16. Regulation of the yield for required sort of monoammonium phosphate by the content of main nutrient substances and the ratio is carried out by change of the SO3 content in dilute phosphoric acid and by change of the mole ratio NH3 : H3PO4 in the ammoniation process. Invention provides enhancing content of total sum of nutrient substances in the fertilizer and enhancing strength index of granules and their homogeneity.

EFFECT: improved preparing method.

2 cl, 4 ex

FIELD: industrial inorganic synthesis.

SUBSTANCE: invention relates to production of ammonium phosphates, notably ammophos, widely used as mineral fertilizers. Process involves neutralization of phosphoric acid with ammonia at elevated pressure, stirring of resulting mixture in static mixer, and subsequent granulation and drying of product. According to invention, neutralization is carried out in two steps: in the first step, 80-85% H3PO4 of its total amount is added and process is carried out at gauge pressure 3.5-8 atm and, in the second step, the rest of acid is added and pressure is lowered to pressure 1.5-3.0 atm. Stirring is effected simultaneously with ultrasonic treatment of the mixture with pulse power from 100 to 1000 W and, before granulation, pressure is lowered by 0.5-0.8 atm relative to pressure of the second neutralization step. Ultrasonic treatment can likewise be employed in the first neutralization step.

EFFECT: improved process control to form uniform improved-quality product and reduced ammonia emission.

2 cl, 3 ex

FIELD: mineral fertilizers.

SUBSTANCE: method of manufacturing complex granulated mineral fertilizer consists in mixing ammonium nitrate and monoammonium phosphate-containing phosphate additive. The latter is granulated mineral double fertilizer simultaneously containing ammonium nitrate, monoammonium phosphate, and calcium phosphates at total content of digestible phosphorus 13÷21% (calculated as P2O5). Additive is introduced by way of melting it followed by admixing resulting melt to molten ammonium nitrate. Phosphate additive utilizes nitroammophosphate at weight ratio N:P2O5 equal to 23:21 or 26:13 and phosphate additive melt is preliminarily completely or partly separated from infusible solid phase, after which phosphate additive is introduced in amount 2-6% (as P2O5) of the weight of final product. Granulated mineral fertilizer contains ammonium nitrate and monoammonium phosphate with total content of digestible P2O5 within a range of 2÷6%, in which case 0.4÷28.6% of P2O5 is present in the form of dicalcium phosphate.

EFFECT: reduced corrosiveness of process medium, increased nutritive value of fertilizer having physicochemical properties competitive with those of known fertilizers, and simplified manufacturing technology.

5 cl, 1 tbl, 5 ex

The invention relates to a method for producing the phosphorus-containing fertilizers such as diammonium phosphate, having a stable dark color of demand in the market
The invention relates to the technology of mineral fertilizers, namely, to obtain from the map solution of ammonium phosphate, which can be used as the phosphorus-containing component is completely water-soluble nitrogen-phosphorus-or nitrogen-phosphorus-potassium fertilizers
The invention relates to a method for producing a complex NPK fertilizers commonly used in agriculture

The invention relates to the technology of production of complex mineral fertilizers, in particular chlorine-free fertilizers by azotnokislogo decomposition of natural phosphates
The invention relates to methods for producing ammonium phosphates, such as monoammonium phosphate and diammonium phosphate, based on the decomposition of phosphate rock with a mixture of phosphoric and sulphuric acids to produce phosphoric acid and its further processing into fertilizer
The invention relates to a method for producing the phosphorus-containing fertilizers such as diammonium phosphate, having a stable dark color of demand in the market

The invention relates to a method for producing a nitrate of an alkali metal and a phosphate of an alkali metal in the same technological process of phosphate and nitrate raw material, comprising the following stages: a) the interaction of phosphate with nitrate raw material with the formation of water nitrophosphates the reaction mixture, with subsequent optional separation of the solid material, (b) introduction of water nitrophosphates the reaction mixture in the first stage of ion exchange carried out in the presence of intense ions of the alkali metal cation-exchange resin to exchange cations present in the reaction mixture, the ions of the alkali metal present in the resin, with the receiving stream, enriched with ions of an alkali metal, C) performing a first crystallization of the stream obtained at step (b), under conditions that ensure the crystallization of nitrate of an alkali metal, and separating the crystallized nitrate of the alkaline metal from the mother liquor, g) the introduction of the mother liquor produced in step (C), the second ion exchange carried out in the presence of intense ions of the alkali metal cation-exchange resin to exchange cations present in the mother solution, the ions of an alkali metal, and d) performing a second crystallization stream obtained at step (g), under conditions that ensure the crystallization of phosphate of an alkali metal, and separating the crystallized phosphate of an alkali metal from the mother liquor

The invention relates to the production of potassium phosphoric acid disubstituted used in the chemical industry for the preparation of pyrophosphate passivating electrolytes and copper plating, as well as in biochemistry for preparation of buffer solutions, while growing the microorganisms in the biosynthesis of antibiotics and enzymes

The invention relates to the production of food phosphates of sodium, used in the food industry as a salt melt with cheese and sausage

The invention relates to the production of phosphates of alkali metals, particularly potassium phosphoric acid one-deputizing used in food, medical and microbiological industry

The invention relates to getting the solution pentamethylcyclopentadienyl

The invention relates to a method for monokaliy used as fertilizer, food additives, as well as in medicine and Microbiology

The invention relates to the production of phosphates of alkali metals, in particular sodium phosphate one-deputizing two-water used in the food industry, and for impregnation of fabrics and wood in order to give them fire

The invention relates to the production of phosphates of alkali metals, in particular of dinatriumfosfaatti used in textile, glass, paint industries, as well as for the cultivation of yeast and water softening in photography and the manufacture of pharmaceuticals

The invention relates to the production of phosphates of alkali metals, in particular sodium phosphate used for water softening, pictures, laboratory practice, as well as in the food, chemical industry
The invention relates to a method for production of trisodium phosphate (FBL), which finds application as a water softener, scale inhibitor, a component of detergents

FIELD: medicine and microbiology; agriculture and food industry; methods of production of monopotassium phosphate.

SUBSTANCE: the invention is pertaining to production of monopotassium phosphate used as fertilizers, food additives, and also in medicine and microbiology. The method provides for neutralization of phosphoric acid by potassium carbonate up to pH not above 4.5 at the heightened temperature, separation of the produced admixture by filtration with the subsequent crystallization and separation of the finished product at cooling. Potassium carbonate take in the form of a water solution with the concentration necessary for production in the neutralized mixture of 23-30 % monopotassium phosphate. The neutralization process is conducted at the temperature of 70-78°C, and the mother liquor after separation of the finished product at the stage of a crystallization return into the process on the stage of dissolution of potassium carbonate. Reaction of the neutralization conduct up to pH = 3.8-4.5. The technical result is an increase of output of the finished product up to 95-97 % and creation of the wasteless production due to utilization of a mother liquor in the process.

EFFECT: the invention ensures increased output of the finished product up to 95-97 %, creation of the wasteless production due to utilization of a mother liquor in the process.

2 cl, 3 ex

Up!