Method capable of lowering synthesis temperature of sodium monofluorophosphate

The invention relates to a method capable of lowering synthesis temperature of sodium monofluorophosphate, which relates to a preparation technology of chemicals and belongs to the field of inorganic chemical industry. In the invention, sodium hexametaphosphate and sodium fluoride are used as main raw materials, and the added fluxing agent is sodium fluosilicate. The method comprises the following specific steps: (a) drying the sodium hexametaphosphate as a raw material for 10-30 minutes at the temperature of 400-520 DEG C, cooling, and grinding; (b) evenly mixing the sodium hexametaphosphateand sodium fluoride as raw materials with the sodium fluosilicate as a fluxing agent; (c) putting the raw materials into a high-temperature furnace, carrying out fusion reaction for 15-30 minutes at the temperature of 590-640 DEG C; and (d) after the reaction, cooling the fused materials, crushing and sieving to obtain the sodium monofluorophosphate product. In the invention, the technological operation ...

一种磷肥副产物综合利用的方法

The method of comprehensively utilizing phosphate fertilizer by-product includes utilizing ammonium fluoride solution of 3-14% concentration to absorb side product fluorine containing tail gas ammonium fluorosilicate solution; adding iron scrap or iron salt to fluorosilicic acid as one other by-product to eliminate phosphorus; adding liquid ammonia, ammonia water or ammonium bicarbonate; filtering, washing, and eliminating silica precipitate; returning ammonium fluoride solution to phosphate fertilizer absorbing system, concentration and drying to obtain ammonium hydrogen fluoride; reacting solid ammonium hydrogen fluoride and sulfuric acid at high temperature to obtain HF gas, absorbing HF gas to obtain hydrofluoric acid, purification and condensation to obtain anhydrous HF; and mixing the mixture of ammonium sulfate and ammonium bisulfate with ammonium bicarbonate or ammonia in a mixer, curing and crushing to ammonium sulfate fertilizer.

Method for continuously preparing white carbon black and ammonium fluoride by carrying out fluosilicic acid ammoniation

The invention discloses a method for continuously preparing white carbon black and ammonium fluoride by carrying out fluosilicic acid ammoniation, which relates to a chemical production method, in particular to a method for preparing the white carbon black and the ammonium fluoride. The method comprises the following steps: (a) at a temperature between minus 5 and 30 DEG C, starting a stirrer and an air compressor, blowing compressed air into an outlet pipe of a reactor by the air compressor and adding fluosilicic acid and ammonia into the reactor simultaneously; (b) when the fluosilicic acid and the ammonia are added to the position of an overflow pipe in the reactor, opening an emptying valve to continuously feed and discharge materials and controlling a PH value of the reaction, wherein the period of the continuous reaction is 24 hours; (c) in the reaction process, filtering the materials discharged by the step (b) to obtain a white carbon black filter cake and filtrate of ammonium fluoride ...

Method for producing silicon carbide from silica gel byproduct in phosphorous fertilizer production

The invention discloses a method for producing silicon carbide from a silica gel byproduct in phosphorous fertilizer production, belongs to the field of inorganic chemical industry, and relates to the technical fields of recycling of the silica gel byproduct in phosphorous fertilizer production and production of the silicon carbide. The silica gel byproduct in phosphorous fertilizer production is taken as a silicon source and the silicon carbide is produced through carbonthermal reduction; and the method comprises the following steps of: a, preprocessing raw materials; b, mixing the raw materials; c, reacting; and d, cooling. By taking the silica gel byproduct in phosphorous fertilizer production as the silicon source, a new product and a new technique for recycling the silica gel byproduct in phosphorous fertilizer production are developed. The method has the advantages of simple process and low cost; the obtained product has the characteristics of high purity, small granularity and the ...

Method for producing pure silicon by using by-product silica gel in phosphate fertilizer industry

The invention relates to a method for producing pure silicon by using by-product silica gel in a phosphate fertilizer industry, which belongs to the fields of inorganic chemical industry, resource comprehensive utilization of the by-product silica gel in the phosphate fertilizer industry and the production technology of pure silicon. In the method, pure silicon is produced from the by-product silica gel in the phosphate fertilizer industry, which is used as a silicon source, by a carbon thermal reduction method. The method comprises the following steps of: a. pretreatment of raw materials; b. material mixing; c. reaction; d. cooling; e. crushing; f. wet purification; g. washing with water to be neutral after the wet purification, and then drying; h. vacuum refining; and i. finally cooling. The invention takes the by-product silica gel in the phosphate fertilizer industry as the silicon source, develops a new product and a new technology of the resource comprehensive utilization of the by-product ...

Cooling-water circulating method for wet phosphoric acid production process

The present invention discloses the cooling water circulating method in wet phosphoric acid production process. One hot water tank is set in some place higher than the water cooling tower inlet, so that the water out of the hot water tank can flow into the water cooling tower for cooling. Compared with available technology, the present invention has no underground channel, underground tank and hot water pump and thus has compact structure, small floor area and low cost.

Method for preparing fluoroboric acid from phosphoric acid by-product fluosilicic acid by wet method

The invention relates to method for preparing fluoboric acid by using wet-process phosphoric acid by-product hydrofluosilicic acid and a chemical production method, in particular to a method for preparing fluoboric acid by using wet-process phosphoric acid by-product hydrofluosilicic acid. The method takes the wet-process phosphoric acid by-product hydrofluosilicic acid and boric acid as raw material and comprises the steps: a. the hydrofluosilicic acid is put into a reactor to be preheated to the temperature of 40-45 DEG C; b. solid boric acid is slowly added into the hydrofluosilicic acid, the ratio between the actual dosage and the theoretical dosage of the boric acid is 0.95-1.05, and the feeding time is 20-30min; c. the reaction is carried out for 2-3h at the temperature of 60-70 DEG C; d. when the reaction stops, feed slurry is filtered, the filtrate is concentrated, filter mass is washed by distilled water, and washing liquid is used for circulating washing; e. the filtrate is concentrated ...

Method for preparing cryolite and coproducing soluble glass by using hydrof luorosilicic acid

The invention discloses a method for preparing cryolite and coproducing soluble glass by using hydrof luorosilicic acid. The method comprises the steps of: adopting phosphoric acid by wet process, phosphate fertilizer and/or hydrof luorosilicic acid which is byproduct of compound phosphate fertilizer to be added to sodium sulfate solution to prepare sodium fluosilicate so as to lead most of impurities such as phosphorus, iron and the like to be distributed to dilute sulphuric acid mother solution for removal; adopting sodium hydroxide to react with the sodium fluosilicate; carrying out filtration washing to obtain sodium fluoride solution; adopting wet filter residue (silica gel) or dried dry filter residue (silica gel) to respectively react with solid sodium hydroxide or sodium hydroxidesolution to coproduce soluble glass adopted as an accessory ingredient of phosphorite floatation; and finally adopting the sodium fluoride to react with aluminium sulphate solution to synthesize thecryolite ...

Method for producing sodium metasilicate pentahydrate with fluorine-containing silica gel

The invention relates to a production method of sodium metasilicate pentahydrate by a fluorin-containing silica gel, in particular to a production method of sodium metasilicate pentahydrate by a fluorin-cotaining silica gel crystallization method. The invention employs fluorin-containing silica gel and liquid alkali or solid soda as production raw materials comprising: a. washing the fluorin-containing silica gel to neutral, mixing the liquid alkali with fluorin-containing silica gel to obtain ingredients; b. sending the ingredients into the reactor to react for 0.5-4 hours at 80-100 DEG C; c. stopping the reaction when the concentration of the solution to be react is 35%-44%; d. cooling the solution and adding the sodium metasilicate pentahydrate with a weight ratio 0.5%-2.5% as a crystal seed, then crystallizing; e. separating the crystal when the temperature reaches 42-36 DEG C after crystallizing for 4-5 hours; f. separating and drying the crystal to obtain sodium metasilicate pentahydrate ...

Sulphur-containing diammonium phosphate fertilizer and production process thereof

The invention provides a fertilizer containing thio-phosphoric acid diammonium, relating to a coated fertilizer, in particular to a fertilizer containing thio-phosphoric acid diammonium added with sulfur and a method for producing the same. The particle surface of the thio-phosphoric acid diammonium fertilizer is sprayed with sulfur melting liquid or coated with a layer of sulfur by the spread coating method or the wrapping method; the sulfur added amount is regulated to produce the thio-phosphoric acid diammonium particle fertilizer with corresponding sulfur content, and the sulfur added amount is 10 to 26 percent of the diammonium phosphate weight. The fertilizer containing thio-phosphoric acid diammonium adopts the technique of adding sulfur on the diammonium phosphate particle surface; the obtained sulfur fertilizer product has high sulfur content, the sulfur in the sulfur fertilizer particle is distributed evenly on the surface of the diammonium phosphate particle, and the sulfur content ...

Method for synthesizing nano 4A molecular sieve from phosphate fertilizer by-product fluosilicic acid

The invention discloses a method for synthesizing a nano 4A molecular sieve by using a phosphate fertilizer by-product, namely, hydrofluosilicic acid, which relates to the synthesis of a nano molecular sieve. The method includes the following steps: a. an ammonium fluoride by-product, namely, silica gel, prepared by an ammonification technology is dissolved in alkali solution to prepare solution with 1.0 mol/l to 1.4 mol/l of Na2O and 2.5mol/l to 3.0 mol/l of SiO2; b. the solution obtained in the step a is used for preparing nano silica sol; c. an aluminum source is dissolved in an alkaline solution to prepare solution with 2.0mol/l to 2.7 mol/l of Na2O and 1.0mol/l to 1.3 mol/l of AI2O3; d. the solution obtained in the step c is used for preparing nano aluminum collosol; e. the nano silica sol obtained in the step b is added into the nano aluminum collosol obtained in the step d and stirred for 5min to 10min, and then 0.1 percent to 1.0 percent of template agent is added and stirred for ...

Method for preparing high reinforcing white carbon black and high concentration ammonium fluoride through ammoniation of fluosilicic acid

A preparation method of highly reinforced white carbon black and high concentration ammonium fluoride through fluosilicic acid ammoniation relates to a preparation method of chemical product, in particular relating to a preparation method of inorganic power material. The invention carries through ammoniation reaction by steps with the fluosilicic acid and ammonia. The white carbon black is acquired after filtrating, washing and drying. The invention is characterized in that the ammonia is added in by steps and the filter is carried through by steps. The steps are that a, 30 to 70 percent of the total ammonia is added in the fluosilicic acid to carry through ammoniation reaction, the reaction liquid is aged, filtrated to acquire a filter cake and a filter liquid; the ammonium fluorosilicate is added in the filter liquid acquired in step a and then the ammonia is added to carry through ammoniation reaction, the reaction liquid is aged, filtrated to acquire the filter cake and the filterliquid ...

Method for improving property of dihydrate wet-process phosphoric acid reaction slurry

The invention discloses a method for improving the performance of dihydrate wet methods phosphoric acid reaction stuff, which comprises the following steps: Classify treating the stuffs by a classifier, the ardealite crystal size of classification bottom current is: the proportion of particles of +40 um size is 90%-95%, 100 um size is 50%-65%, +150 um size is 20%-35%. Filtering and washing the classification bottom current in a filter. The ardealite crystal size of classification overflow is: the proportion of particles of -40 um size is 80%-85%, -100 um size is 100%. Growing and increasing further have the classification overflow in a seed crystal reaction tank and entering the next classified cycle. Taking the ardealite filtrated and washed to the slag ground, and taking the diluted phosphoric acid to the storage tank, returning the preliminary filter liquid and 1st cleaning solution to the reaction tank, and quadratic countercurrent washing the 2nd cleaning solution in the filter.

Method for separating sodium fluoride crystals from silicon dioxide

The invention relates to a method for separating sodium fluoride crystals from silicon dioxide, in particular to a method for jointly producing sodium fluoride and sodium silicate by using sodium fluosilicate which is a by product of phosphate fertilizer production. The method of the invention comprises: a, stirring a sodium fluosilicate solid and 30 to 50 percent solution of sodium carbonate with a big force to perform a reaction to obtain solution containing sodium fluoride crystals and a silicon dioxide precipitate; b, adding sodium hydroxide into the solution obtained by the step a in a theoretical dose based on a molar ratio of Na2O to SiO2 of 30 to 50 percent to dissolve the silicon dioxide to form solution of sodium silicate and the sodium fluoride crystals, wherein the concentration of the solution of the sodium hydroxide is 45 to 50 percent; c, centrifugally filtering the solution obtained by the step b, washing solid sodium fluoride, and drying the sodium fluoride to obtain a ...

Method for separating residual fluorine from by-product silica gel prepared in process of producing fluoride salt from fluorosilicic acid

The invention discloses a method for separating residual fluorine from a by-product namely silica gel prepared in a process of producing fluoride salt from fluorosilicic acid. The method comprises the following steps: dissolving a by-product namely silica gel which is prepared in a process of producing fluoride salt from fluorosilicic acid into a sodium hydroxide or sodium carbonate solution to prepare a solution of which the silicate-sodium molar ratio is (2.5-3.4):1 and the solid content is 5-20%; by adopting an ion exchange process, respectively removing a cation Na<+> by virtue of cation exchange resin and removing an anion F<-> by virtue of anion exchange resin; and then performing ultra-filtration and concentration to obtain silica sols of which residual fluorine is removed. By adopting the method disclosed by the invention, residual fluorine in the by-product namely silica gel can be effectively removed, and by virtue of actual detection, 99.99% of residual fluorine can be removed ...

Method for preparing cryolite and coproducing soluble glass by using hydrof luorosilicic acid

The invention discloses a method for preparing cryolite and coproducing soluble glass by using hydrof luorosilicic acid. The method comprises the steps of: adopting phosphoric acid by wet process, phosphate fertilizer and/or hydrof luorosilicic acid which is byproduct of compound phosphate fertilizer to be added to sodium sulfate solution to prepare sodium fluosilicate so as to lead most of impurities such as phosphorus, iron and the like to be distributed to dilute sulphuric acid mother solution for removal; adopting sodium hydroxide to react with the sodium fluosilicate; carrying out filtration washing to obtain sodium fluoride solution; adopting wet filter residue (silica gel) or dried dry filter residue (silica gel) to respectively react with solid sodium hydroxide or sodium hydroxide solution to coproduce soluble glass adopted as an accessory ingredient of phosphorite floatation; and finally adopting the sodium fluoride to react with aluminium sulphate solution to synthesize the cryolite ...

Method for preparing fluoroboric acid using by-product fluosilicic acid with low concentration in wet method phosphoric acid production process

The invention discloses a method for preparing fluoboric acid from a byproduct, namely low-concentration hydrofluosilicic acid of phosphorous acid by a wet process and preparation of the fluoboric acid, and in particular relates to the method for preparing the fluoboric acid by inducing the crystallization by the byproduct, namely the low-concentration hydrofluosilicic acid of the phosphorous acid by the wet process. The method comprises the following steps that: a, the low-concentration hydrofluosilicic acid is sent into a reactor, silicon dioxide is added into the reactor to serve as an inoculating seed, and the stirring is performed; b, a suspension of the hydrofluosilicic acid and the silicon dioxide is preheated to a temperature which is more than 50 DEG C; c, solid boric acid is slowly added into the hydrofluosilicic acid, the ratio of the actual use level to the theoretical use level of the boric acid is between 0.95 and 1.05, and the adding time is between 60 and 70min; d, the mixture ...

Method for preparing big-compensating forcing white carbon black and high concentration ammonium fluoride through aminating of fluosilicic acid

A preparation method of highly reinforced white carbon black and high concentration ammonium fluoride through fluosilicic acid ammoniation relates to a preparation method of chemical product, in particular relating to a preparation method of inorganic power material. The invention carries through ammoniation reaction by steps with the fluosilicic acid and ammonia. The white carbon black is acquired after filtrating, washing and drying. The invention is characterized in that the ammonia is added in by steps and the filter is carried through by steps. The steps are that a, 30 to 70 percent of the total ammonia is added in the fluosilicic acid to carry through ammoniation reaction, the reaction liquid is aged, filtrated to acquire a filter cake and a filter liquid; the ammonium fluorosilicate is added in the filter liquid acquired in step a and then the ammonia is added to carry through ammoniation reaction, the reaction liquid is aged, filtrated to acquire the filter cake and the filter liquid ...

Multistage closed wet phosphate rock grinding process

The multistage closed wet phosphate rock grinding process combines rod milling and ball milling, and includes the first section rod milling, the second section ball milling, inclined plate grading and densifying. The rod milling raises the rock grinding selectivity; the inclined plate grading machine results in high grading quality and efficiency and less over-milling; and the densifying machine of stepped overflow reaches the required density.

Cooling-water circulating method for wet phosphoric acid production process

Method for separating sodium fluoride crystals from silicon dioxide

The present invention relates to a method for separating sodium fluoride crystals from silicon dioxide, in particular to a method for jointly producing sodium fluoride and sodium silicate by using sodium fluosilicate which is a by product of phosphate fertilizer production. The method of the invention comprises: a, stirring a sodium fluosilicate solid and 30 to 50 percent solution of sodium carbonate with a big force to perform a reaction to obtain solution containing sodium fluoride crystals and a silicon dioxide precipitate; b, adding sodium hydroxide into the solution obtained by the step a in a theoretical dose based on a molar ratio of Na2O to SiO2 of 30 to 50 percent to dissolve the silicon dioxide to form solution of sodium silicate and the sodium fluoride crystals, wherein the concentration of the solution of the sodium hydroxide is 45 to 50 percent; c, centrifugally filtering the solution obtained by the step b, washing solid sodium fluoride, and drying the sodium fluoride to obtain ...

Method for preparing fluoroboric acid using by-product fluosilicic acid with low concentration in wet method phosphoric acid production process

The invention discloses a method for preparing fluoboric acid from a byproduct, namely low-concentration hydrofluosilicic acid of phosphorous acid by a wet process and preparation of the fluoboric acid, and in particular relates to the method for preparing the fluoboric acid by inducing the crystallization by the byproduct, namely the low-concentration hydrofluosilicic acid of the phosphorous acid by the wet process. The method comprises the following steps that: a, the low-concentration hydrofluosilicic acid is sent into a reactor, silicon dioxide is added into the reactor to serve as an inoculating seed, and the stirring is performed; b, a suspension of the hydrofluosilicic acid and the silicon dioxide is preheated to a temperature which is more than 50 DEG C; c, solid boric acid is slowly added into the hydrofluosilicic acid, the ratio of the actual use level to the theoretical use level of the boric acid is between 0.95 and 1.05, and the adding time is between 60 and 70min; d, themixture ...

Multistage closed wet phosphate rock grinding process