86results about "Ammonium fluoride" patented technology

Provided is a novel method and system for preparing ultra-high-purity buffered-hydrofluoric acid or ammonium fluoride controlled concentration. The method comprises bubbling purified ammonia vapor into ultra-pure hydrofluoric acid. The inventive method and system can be used as an on-site subsystem in a semiconductor device fabrication facility for supplying the buffered-hydrofluoric acid and ammonium fluoride to points of use in the semiconductor device fabrication facility.

The invention discloses a recycling method for fluorine-containing ammonia-nitrogen-containing wastewater through tantalum-niobium wet-process smelting, and relates to the technical field of wastewater recycling. The recycling method comprises the following steps: adding hydrofluoric acid or sulfuric acid into wastewater to regulate the pH value of the wastewater to 5-6, completely converting freeNH3 in the wastewater into NH<4+> for being dissolved into the wastewater, performing primary screening on mixed salt wastewater into an ammonium fluoride solution and an ammonium sulfate solution through a primary nanofiltration membrane system, pumping the primarily separated ammonium fluoride solution into a secondary nanofiltration membrane system, removing a little ammonium sulfate in the ammonium fluoride solution, wherein a little ammonium fluoride is contained in the primarily separated ammonium sulfate solution; arranging a fluorine ion concentration online monitor in the primary nanofiltration membrane circulating system until concentration of fluorine ions is lower than a set value; automatically opening an electric regulating valve for discharging the ammonium sulfate solutionwith purity reaching design requirements out of the primary nanofiltration membrane system; and introducing the concentrated ammonium fluoride solution and the concentrated ammonium sulfate solutioninto a low-temperature membrane evaporation and crystallization system, thereby recycling ammonium fluoride crystals and ammonium sulfate crystals.

The invention discloses a resourceful treatment method of waste salt. The method comprises the following steps: S1, a waste salt pretreatment stage: removing insoluble impurities in waste salt, and separating and enriching water-soluble ions to obtain mixed hybrid salt mainly comprising sodium sulfate and sodium chloride; S2, a double decomposition stage: carrying out double decomposition reaction on the mixed hybrid salt; S3, filtering a metathesis mixed solution obtained by the metathesis reaction, and collecting filter cake obtained by filtering to enter a sodium bicarbonate preparation stage; and S4, an ammonium salt preparation stage. The waste salt mainly containing sodium chloride and sodium sulfate is subjected to resourceful treatment, industrial sodium bicarbonate and ammonium salt products are obtained, so that resourceful treatment of the waste salt is greatly improved. The method is simple in process and low in cost, the utilization rate of the waste salt is 84%-89%, the purity of the prepared product sodium bicarbonate is 94%-96%, and the nitrogen content (on a dry basis) in the ammonium salt is greater than or equal to 23.8%.

Nitrogen trifluoride is produced with a high yield by the method comprising forming a fast stream of micro droplets of a fused ammonium fluoride salt by rapidly ejecting the fused ammonium fluoride salt into a reactor through a nozzle while circulating the fused ammonium fluoride salt in the reactor from a lower portion to an upper portion; and contacting micro droplets of the fused ammonium fluoride salt with fluorine gas sucked in the reactor through a suction pipe for fluorine by a negative pressure formed around the nozzle due to an ejection of the fused ammonium fluoride salt, whereby excessive generation and regional accumulation of the heat of reaction are prevented, reducing the reaction temperature by 10˜30° C. compared with those of the existing methods, and a side reaction occurs only to a slight extent according to the lowered reaction temperature.

F2 gas is reacted with NH3 gas in a gaseous phase at 80° C. or less in the presence of a diluting gas to produce NF3. Thus, NF3 is produced with good safety, efficiency and profitability.

The invention provides a method for preparing ammonium bifluoride from BOE waste liquid, which can avoid environmental pollution caused by directly discharging the BOE waste liquid by recycling the BOE waste liquid, and the recovered and prepared ammonium bifluoride product has the advantages of high purity, low water content, low investment cost and low production cost. According to the method, BOE waste liquid generated by a semiconductor etching process is used as a raw material, barium hydroxide is used as a precipitator to remove impurities in the waste liquid, then anhydrous hydrogen fluoride is introduced to convert ammonium fluoride into ammonium hydrogen fluoride, and then evaporation, cooling crystallization, centrifugal separation and drying are performed to obtain high-purity ammonium hydrogen fluoride with low water content.

The invention discloses a preparation method of ammonium bifluoride. The method comprises steps as follows: a, dilute ammonia water and ammonium bifluoride mother liquor are mixed to adsorb gas containing fluorine and silicon, and a mixed solution is obtained; b, the mixed solution and filter-press residues obtained in Step d are mixed for slurry making and filter-press separation, and a filtrate and a silica by-product are obtained; c, ammonia is introduced into the filtrate; d, slurry is subjected to filter-press separation, and an ammonium fluoride filtrate and filter-press residues are obtained; e, the ammonium fluoride filtrate is subjected to vacuum concentration; f, concentrated slurry is dissolved, the pH value of the solution is adjusted with hydrogen fluoride, and cooling crystallization is performed; g, ammonium bifluoride crystals are filtered, separated and dried, and the ammonium bifluoride product is obtained. With the adoption of the method, the utilization rate of fluorine and ammonia is increased, the gas containing fluorine and silicon is changed into the ammonium bifluoride product with the high economic value in the phosphoric acid production process, the production cost is low, the economic benefit is significant, meanwhile, the purity and other indexes of the product meet the requirement for superior products, and the method is suitable to be popularized and applied in the field.

The invention provides a method for refining and purifying waste etching liquid. The method comprises the following steps: sequentially evaporating, cooling and crystallizing waste liquid generated by an etching process to obtain a crude ammonium bifluoride product and steam; dissolving the crude ammonium bifluoride product again, then performing adsorption, subjecting the adsorbed solution to nanofiltration, and conducting refining so as to obtain a refined etching solution; and condensing the steam to obtain a condensate, adsorbing the condensate, and performing reverse osmosis to obtain reverse osmosis concentrated water and reverse osmosis fresh water. According to the method, evaporation and cooling crystallization treatment are conducted on the etching waste liquid, preliminary purification is carried out to obtain a crude ammonium bifluoride product, and then the crude ammonium bifluoride product is dissolved and then subjected to adsorption and nanofiltration treatment for refining so as to obtain electronic-grade-purity ammonium bifluoride; steam in the evaporation stage is separated and purified through condensation, adsorption and reverse osmosis treatment, so comprehensive treatment of the etching waste liquid is integrally achieved; and the method is simple in process, low in raw material price and operation cost and wide in application range.

The invention relates to a treatment method of fluorine-containing nickel slag generated in a nitrogen trifluoride preparation process, and belongs to the technical field of harmless treatment of nickel-containing hazardous wastes. The method comprises the following steps: (1) crushing the fluorine-containing nickel slag into solid powder; (2) dissolving the fluorine-containing nickel slag solid powder by using a hydrofluoric acid solution, performing stirring at 30-60 DEG C, and adding an oxidizing substance in the stirring dissolution process until the fluorine-containing nickel slag is completely dissolved to obtain a mixed solution a; (3) adjusting the pH value of the mixed solution a to 3.5-4.5 by using ammonia water, and performing filtering to obtain ferric hydroxide precipitate and a mixed solution b; and (4) continuing to adjust the pH value of the mixed solution b to 6.5-7.5 with the ammonia water, performing filtering to obtain nickel fluoride and a mixed solution c, heating and concentrating the mixed solution c, and performing cooling crystallizing to obtain ammonium fluoride and a mixed solution d. The method realizes recovery and cyclic utilization of nickel metal resources and ammonium fluoride, and can significantly reduce the production cost of nitrogen trifluoride.

The invention discloses a method for recovering ammonium fluoride from ammonium fluoride wastewater, which comprises the following steps: S1, adding hydrofluoric acid into the ammonium fluoride wastewater, regulating the pH value of the wastewater to 5-6, converting NH3 in the wastewater into ammonium fluoride salt, and dissolving the ammonium fluoride salt in the wastewater; and S2, pumping the ammonium fluoride waste water with the pH adjusted into an evaporator, keeping the interior of the evaporator in a vacuum environment, carrying out reduced-pressure constant-temperature evaporation onthe ammonium fluoride waste water in the evaporator at the evaporation temperature of 50-70 DEG C for 1-5 hours, continuously separating out crystallized ammonium fluoride in the evaporation process,and recycling the generated condensate water. According to the method for recycling the ammonium fluoride from the ammonium fluoride wastewater, solid waste pollutants cannot be generated in the recycling process, secondary pollution is avoided, the evaporation temperature of the evaporator is low, the evaporation cost is greatly reduced, the ammonium fluoride is recycled, condensate water is recycled, resources are reutilized, and extra economic benefits are generated.

The invention discloses a method for reducing ammonium fluorosilicate in ammonium fluoride. The method comprises the steps as follows: fluosilicic acid is subjected to an amination reaction to producean ammonium fluoride mixed solution containing silicon dioxide, wherein the mass concentration of ammonium fluoride is 20%-35%, the mass concentration of silicon dioxide is 2%-15%, and the PH value is 8.0-10; the ammonium fluoride mixed solution is filtered by a filter press, most silicon dioxide is removed, and an ammonium fluoride solution containing a little silicon dioxide is obtained; the ammonium fluoride solution containing a little silicon dioxide is left to stand and clarified in a filtrate tank for 1-3 h, most silicon dioxide settles to the bottom, an upper clear ammonium fluoride liquid is subjected to refined filtration by micropores with the diameter being 3-10 micron again, and a wet filter cake returns to a feeding tank of the filter press; a filtrate enters a concentratedraw material tank to be left to stand and clarified for 1-3 h, an upper clear ammonium fluoride liquid is taken to enter a concentration system, conventional concentration, ammonia introduction, crystallization and centrifugal separation are performed later and an ammonium fluoride product is obtained. The method can effectively reduce ammonium fluorosilicate in ammonium fluoride and is low in energy consumption and environmentally friendly.

The invention discloses a system for purifying waste gas generated in lithium battery recovery and recovering resources. The system comprises a pyrolysis device, a second dust removal device, a gas mixer, a combustion chamber and a boiler, which are connected in sequence; a splitting device, a first dust removal device and a gas mixer are sequentially communicated; and a hydration tower, a first-stage phosphoric acid catcher, an acid mixing tank, a second-stage phosphoric acid catcher, a hydrofluoric acid recovery tower and a purification tower are sequentially communicated. The invention alsodiscloses a method for purifying waste gas generated in lithium battery recovery and recovering resources. The method has the advantages that the separation and purification of P2O5 and HF are realized, the combustion energy of carbonic ester organic matters is utilized, and byproducts such as phosphoric acid, hydrofluoric acid or ammonium fluoride are extracted in a grading manner, so that the treatment difficulty of wastewater and waste residues is greatly reduced, and the method is environment-friendly. In addition, due to the fact that byproducts are high in market value at present, the environment-friendly project has good economic benefits in operation, and resources are saved.

The invention relates to a cleaning treatment method for ammonium chloride production wastewater. The method comprises the specific steps that during the separation and purification process of ammonium chloride, residual liquid after rectification of methanol passes through a two-effect evaporation system, a first-effect evaporation system and a decompression flashing system, and a high-ammonia nitrogen and COD content condensed water obtained from the two-effect evaporation system and the decompression flashing system is directly reused in a chloroacetic acid method glycine production process. The water obtained by the first-effect evaporation system is treated by a vacuum low-temperature evaporation system, the obtained low-ammonia nitrogen condensed water is used as a raw material for industrial grade ammonia production, and the residual liquid is directly reused in the chloroacetic acid method glycine production process. The method has small investment in equipment, the evaporationcondensed water treatment is harmless, and the method is energy-saving and environmentally friendly, and is suitable for the chloroacetic acid method glycine production process.

The present invention is directed to an organic polymerizable composition for producing a molded polymeric article. The composition includes a mold release agent of ionic fluoride and/or ionic fluoride precursor present in an amount sufficient to effect at least partial demolding of the polymeric article from a mold. Molded articles also are provided.

The invention discloses a production process for preparing low-silicon ammonium bifluoride by using fluosilicic acid as a raw material, which comprises the following steps: by using a fluosilicic acidsolution as a raw material, carrying out ammoniation desilicication and filtration to obtain an ammonium fluoride primary solution; and then adding a desilicication agent into the ammonium fluoride primary solution to carry out secondary desilicication, and then filtering, concentrating and crystallizing to obtain an ammonium hydrogen fluoride product. The content of fluosilicic acid radicals inthe ammonium bifluoride product is lower than 0.2%, and the application value of the byproduct fluosilicic acid is greatly improved.

The invention belongs to the field of analysis and detection, and particularly relates to a reagent purification device and a method for purifying ammonium bifluoride or ammonium fluoride by using thesame, the reagent purification device enables NH4HF2 or NH4F steam to be crystallized in situ at different positions of a reagent collection bottle in an integral heating and step-by-step cooling manner. The purification device is of a vertical full-closed structure, temperature and time parameters can be designed in advance through programs, and automatic purification is achieved. The equipmentprinciple is simple, multiple units can be combined for use, a large number of NH4HF2 or NH4F reagents are purified at a time, and high efficiency, simplicity and convenience are achieved.

The invention discloses a preparation system and process of an electronic-grade ammonia fluoride. The preparation system mainly comprises a mixing tank, an evaporator, a mixer and a finished product tank; one side of the mixing tank is connected with a hydrofluoric acid intermediate tank; one side of the evaporator is connected with a liquid ammonia storage tank; the mixer is connected with the evaporator through a filter pipe; a circulating pipe group is connected between the mixer and the mixing tank; and the finished product tank is connected with the mixer. The preparation system providedby the invention is simple in structural composition; complex procedures are orderly and simply materialized, so that complexity is decreased; the systematization of an electronic-grade ammonium fluoride production process is realized, and quantitative production of enterprises under relatively economic conditions is facilitated; and the preparation process provided by the invention is operated onthe basis of adopting the basic support of the main body of the above main structure, so that the whole process is ordered and clear, electronic-grade ammonium fluoride finished products can be prepared in batches, and the advantages of relatively economical cost and relatively high production efficiency can be achieved.

The invention provides a process for extracting a silicon fertilizer from fluorite waste liquid. The process comprises the following steps: heating and concentrating the fluorite waste liquid at 100-150 DEG C, so as to obtain mixed gas and a mixed solid; grinding the mixed solid, and sieving by virtue of a 200-mesh sieve, so as to obtain mixed solid powder; carrying out cyclone separation on the mixed solid powder, so as to obtain a silicon-containing mixture; and carrying out magnetic separation on the silicon-containing mixture, so as to obtain the silicon fertilizer finished product. The method has the beneficial effects that elements such as potassium, sodium, silicon and fluorine in the fluorite waste liquid can be adequately utilized, so that the production cost of fluorite is lowered; meanwhile, the environmental pollution caused by direct emission of the fluorite waste liquid is avoided; the method is simple, feasible and suitable for large-scale application.

The invention discloses a method for reducing ammonium fluorosilicate in ammonium bifluoride. The method comprises the steps as follows: fluorosilicic acid is subjected to an ammoniation reaction anda silicon dioxide-containing ammonium fluoride mixed solution is obtained, wherein the mass concentration of ammonium fluoride is 20%-35%, the mass concentration of silicon dioxide is 2%-15%, and thePH value is 8.0-10; the ammonium fluoride mixed solution in step (1) is filtered by a filter press, most silicon dioxide is removed, a filtrate enters a filtrate tank and left to stand and clarified for 1-3 h, most silicon dioxide settles to the bottom, and the upper layer is a clear ammonium fluoride liquid; the upper clear ammonium fluoride liquid in step (2) is finely filtered again by micropores with the diameter being 3-10 micron, and a wet filter cake returns to a feeding chute of the filter press; a refined filtrate enters a concentrated raw material chute to be left to stand and clarified for 1-3 h, an upper clear ammonium fluoride liquid enters a concentration system, conventional concentration, acid addition, crystallization and centrifugal separation are performed later, and anammonium bifluoride product is obtained. The method can effectively reduce ammonium fluorosilicate in ammonium bifluoride, has low energy consumption, introduces no other impurities and avoids waste emission.

The invention discloses a device and process for producing byproducts ammonium bifluoride and potassium fluoride from NF3 production, and the device comprises a workbench; a groove is formed in the middle of the upper end of the workbench, a conveying mechanism is arranged in the groove, electric push rods are fixed to the two sides of the upper end of the workbench, lifting blocks are fixed to one ends of the two electric push rods, a lifting plate is fixed to one ends of the two lifting blocks together, and a mounting frame is fixed to one side of the upper end of the lifting plate. The invention further provides a process for producing ammonium bifluoride and potassium fluoride as byproducts in NF3 production. Filling and installation of the bottle cap can be achieved through intermittent movement of the bottle body, the labor cost is effectively saved, dust is prevented from flying out, the production efficiency is improved, hazardous waste containing nickel and fluorine can be eliminated and converted into by-products, environmental pollution is reduced, and the method can convert the original hazardous wastes needing to be treated into byproducts, and has certain economic benefits.