384 results about "Fluoride calcium" patented technology

The invention provides a method for decomposing and mineralizing fluorine-containing organic matter wastewater, which is applied to the technical field of treatment of fluorine-containing organic matter wastewater generated in a perfluoroether elastomer emulsion flocculation process, and comprises the following steps: S1, carrying out adsorption and desorption treatment on the fluorine-containing organic matter wastewater to obtain a concentrated solution of the fluorine-containing organic matter wastewater; s2, hydrogen peroxide and ferrous ions are added into a container containing the concentrated solution to obtain a mixed solution, the pH of the mixed solution is adjusted to be 2-4, the concentration mass ratio of the hydrogen peroxide to organic matter contained in the fluorine-containing organic matter wastewater is 1: 1-2, the molar ratio of the hydrogen peroxide to the ferrous ions is 1-6: 1, micro-nano bubbles are introduced into the mixed solution, and ultrasonic treatment is conducted; s3, calcium hydroxide is added into the treated mixed solution, calcium fluoride precipitates are obtained through centrifugal treatment, and the fluorine-containing organic matter in the wastewater can be degraded and mineralized.

The invention discloses a grading reaction crystallization recovery process and system for semiconductor fluorine-containing and phosphorus-containing waste liquid, the fluorine-containing and phosphorus-containing waste liquid and a lime solution react in a fluorine recovery crystallization reactor under the condition that the pH is 3-4 to form calcium fluoride crystals, and the calcium fluoride crystals are dehydrated to obtain calcium fluoride particle crystal products; the effluent of the fluorine recovery crystallization reactor, the calcium fluoride crystal dehydration filtrate, the lime solution and the calcium chloride solution react in a secondary reaction tank under the condition that the pH is 5-6, and calcium fluoride, fluorapatite, silicon dioxide and silicon-aluminum precipitates are removed through coagulation, flocculation and precipitation; effluent of the second-stage reaction tank, the lime solution and the calcium chloride solution react in the phosphorus recovery crystallization reactor under the condition that the pH is 7-8 to generate hydroxyapatite crystals, and the hydroxyapatite crystals are dehydrated to obtain hydroxyl calcium phosphate particle crystal products. Meanwhile, a high-purity calcium fluoride crystal product and a hydroxyl calcium phosphate crystal product are produced, and fluorine and phosphorus are recycled.

The invention belongs to the technical field of industrial wastewater treatment and resource recovery, and particularly relates to an enhanced treatment method for recovering fluorine resources in semiconductor processing fluorine-containing wastewater. And step-by-step efficient recovery of sodium fluosilicate and calcium fluoride is realized through cooperation of precipitant compounding and pH regulation. The method comprises the following steps: firstly, adding a NaCl-NaHCO3 composite precipitator and sodium fluosilicate seed crystals to induce crystallization and recover hexagonal prism-shaped sodium fluosilicate single crystals; and after filtering, adding a CaCl2-Ca (OH) 2 composite precipitator and calcium fluoride seed crystals into the filtrate to generate large-particle calcium fluoride. And the impurity content in the recovered product respectively reaches the industrial sodium fluosilicate superior product standard and the metallurgical grade calcium fluoride secondary product standard. And the treated wastewater is neutral or weakly alkaline, so that the subsequent mixed treatment with other wastewater is facilitated.

The invention relates to a large-size glass product with a natural ice crystal imitating effect and an industrial casting method of the large-size glass product. The product is a lead-free glass casting with the weight larger than or equal to 100 kg, dendritic crystal-shaped or snowflake-shaped devitrified phases which are formed by growing calcium fluoride as crystal nucleuses and are distributed randomly are arranged in the product, and the three-dimensional aesthetic effect imitating natural ice crystals is achieved. The method comprises the following steps: mixing lead-free glass particles with a calcium fluoride nucleating agent with a specific particle size, and filling a mixture into a special mold with a three-layer composite structure and a temperature monitoring function; and executing a four-stage programmed thermal regulation including melting homogenization, nucleation cooling, isothermal crystallization and super-slow multi-step annealing, wherein the melting and heat preservation time and the maximum thickness of the product meet the quantitative relation of t = k.H. Through systematic collaboration of materials, molds and processes, the technical problems that crystallization in large-size glass is not uniform and cracking is easily caused by thermal stress are solved, high yield and stable mass production of products of 500 kg or above are achieved, and the method is suitable for the fields of high-end buildings, art devices and decoration.

The invention provides a zinc-copper-nickel-copper smelting deslagging agent and a preparation method and a use method thereof. The zinc-copper-nickel-copper smelting deslagging agent comprises the following raw materials in percentage by mass: 5-15% of calcium fluoride, 20-30% of sodium carbonate, 5-15% of sodium fluoride, 10-20% of sodium hexafluoroaluminate and the balance of borax. Compared with the prior art, the zinc-copper-nickel-copper slag remover prepared by mixing the raw materials can effectively reduce impurities to be less than 0.14% of Fe, less than 0.005% of Pb and less than 0.003% of Si in the smelting process, the impurity components are obviously reduced, the number of times of component adjustment and unqualified sampling is reduced, impurities mixed in a casting blank are reduced, and finally the metal purity and the casting quality are improved. Meanwhile, loss of zinc and nickel is reduced to the maximum extent; and adverse effects on the zinc-copper-nickel alloy are avoided.

The application discloses a device for reducing fluorine-containing gas pollutant emission in electroslag remelting and a use method, which comprises a flue gas recovery cover (1), a flue gas discharge pipeline (7) and a purification tank (10). The flue gas recovery cover (1) is respectively provided with a remelted slag discharging hole (2), a self-consuming mother electrode (6) passing hole and a flue gas discharge pipeline (7) mounting hole. The flue gas discharge pipeline (7) is arranged through the flue gas discharge pipeline (7) mounting hole, one end of the flue gas discharge pipeline (7) is located in a closed space formed by the flue gas recovery cover (1) and a crystallizer (5), and the other end is inserted into the purification tank (10). A fan (8) is arranged on the flue gas discharge pipeline (7). Through the device, the fluorine-containing flue gas is recovered, and the fluorine-containing flue gas is converted into calcium fluoride by using an alkali solution. The device can realize the cyclic and repeated use of part of the calcium fluoride, greatly reduces the concentration of fluorine-containing harmful gas in the air environment of an electroslag remelting operation site, and makes the concentration of the fluorine-containing harmful gas reduce from the original 5.6 mg / m 3 to 0.02 mg / m 3 .

The invention relates to a method for recovering lithium and fluorine from aluminum electrolysis hazardous waste, which comprises the following steps: firstly, mixing organic polyol and alkaline hydroxide according to a molar ratio of 1: (0.5-2) to obtain a eutectic solvent; heating the eutectic solvent to 80-150 DEG C, and adding a proper amount of raw material fine powder and calcium oxide for reaction leaching; carbonating and filtering the leachate to obtain lithium carbonate; washing the leaching residues with an acetic acid solution to obtain a calcium fluoride product; the concentration of fluorine ions in the leachate is smaller than or equal to 200 ppm, and the purity of calcium fluoride is larger than or equal to 90%; the leaching rate of lithium in the method is greater than 85%; the slag feeding rate of fluorine is greater than 95%; and no hydrogen fluoride gas is generated in the method. According to the method, a non-toxic and biodegradable eutectic solvent is adopted as a leaching agent, and efficient leaching of lithium and fluorine in the aluminum electrolysis dangerous waste materials is achieved; calcium oxide is used as a precipitating agent, free fluorine is promoted to be precipitated and recycled as calcium fluoride, the whole process meets the requirement of green metallurgy, and the win-win situation of resources and the environment is achieved.

The invention discloses a method for recovering high-purity fluorine and silicon from fluorine-silicon slag and co-producing a low-alkali fluorine-free accelerator, which comprises the following steps: S1, dissolving the fluorine-silicon slag in a sodium hydroxide solution to obtain a solution A; s2, adding dilute sulphuric acid into the solution A, reacting until gel is obtained, and filtering to obtain filtrate A and high-purity silicon dioxide gel; s3, adding calcium sulfate and EDTA (Ethylene Diamine Tetraacetic Acid) into the filtrate A, stirring and reacting, and filtering after the reaction is finished to obtain calcium fluoride and filtrate B; and S4, taking clear water, heating, carrying out heat preservation, then adding aluminum sulfate, lithium sulfate, diethanol amine and the filtrate B obtained in S3, continuously stirring until the aluminum sulfate is completely dissolved, then adding hydrated magnesium silicate, continuously carrying out heat preservation stirring, and obtaining the low-alkali fluorine-free accelerator after stirring is finished. The method is simple in process and easy to implement industrially, and fluoride and silicon oxide obtained through separation are high in purity and beneficial to follow-up extension application; more importantly, high-value recycling of the fluorosilicon slag is achieved, and the problems of stockpiling waste and environmental pollution of the fluorosilicon slag are solved.

Processes and apparatuses for degrading PFAS into calcium fluoride, carbon dioxide, and water. PFAS are heated and introduced to a calcium base which will degrade the PFAS. The PFAS may be in a stream that is a PFAS enriched stream formed by desorbing the PFAS from an adsorbent which removed the PFAS from a contaminant stream. The PFAS may be desorbed in the presence of the calcium base. The calcium base may be calcium hydroxide, calcium oxide, calcium carbonate, or combinations thereof.

A hydrocarbon gas detection system including a longwave infrared camera, a spectral filter, and a computation unit. The spectral filter is disposed in the light path of the camera sensor. The spectral filter is made of a material selected from the group consisting of calcium fluoride, zinc sulfide, magnesium fluoride, and silicon. The computation unit is arranged to process image data of the longwave infrared camera for the hydrocarbon gas detection.

The invention discloses a method for comprehensively recycling electrolytic aluminum carbon residues, and relates to the technical field of comprehensive recycling of waste materials. The method for comprehensively recycling the electrolytic aluminum carbon residues comprises the following steps of: breaking the carbon residues into 0.1-1cm particles by a hammer, carrying out wet ball milling under the condition of adding a flotation agent, and separating carbon powder on the upper layer and gray regenerated cryolite on the bottom layer of slurry through flotation equipment, wherein the fineness is 40-100 meshes, and the carbon content is less than 1%; the preparation method comprises the following steps: adding water into cryolite to prepare slurry, adding calcium oxide or calcium hydroxide, heating, stirring and reacting for 1-3 hours, and carrying out filter pressing to obtain filtrate and filter residues which are calcium fluoride and a sodium metaaluminate solution; the purity of the calcium fluoride powder is greater than 85%; and introducing hydrochloric acid into the filtrate, stirring and adjusting the pH to 7-9 to obtain aluminum hydroxide slurry, filtering and washing to obtain aluminum hydroxide, and drying to obtain the aluminum hydroxide with the purity of more than 95%.

The invention discloses a fluorine-containing wastewater advanced treatment system and a fluorine-containing wastewater advanced treatment method based on cooperation of chemical precipitation and a membrane method. Comprising a sedimentation tank, a dynamic filter and a double-membrane system which are arranged in sequence, wherein in the sedimentation tank, a modified calcium salt precipitator and CaF2 seed crystals are added into the fluorine-containing wastewater for reflux, and large calcium fluoride particle precipitates are formed through an induced crystallization adsorption-sedimentation mechanism; the dynamic filter is used for intercepting sediments from effluent of the sedimentation tank through a gradient aperture structure to realize solid-liquid separation and preliminary fluorine removal; and the double-membrane system is used for removing residual fluorine-containing particles, colloids and ions in the wastewater treated by the dynamic filter by utilizing an ultrafiltration membrane and a reverse osmosis membrane. Through cooperation of a modified calcium salt adsorption-precipitation mechanism and a membrane gradient interception method, efficient trapping and solid-liquid separation of fluorine ions are achieved, the fluorine removal precipitation reaction is enhanced, the medicine consumption is reduced, and near-zero external water consumption is achieved.

The utility model provides a multistage deep defluorination device for fluorine-containing wastewater. The multistage deep defluorination device comprises a crystallization tank, a coagulation tank, a coagulation aid tank, a flocculation tank, a precipitation water distribution tank and an efficient precipitation tank which are connected in sequence, a calcium chloride solution adding pipe is arranged in the crystallization tank; a first stirrer, a coagulant feeding pipe and an alkali liquor feeding pipe are arranged in the coagulation tank; a second stirrer and a particle medium adding mechanism are arranged in the coagulation aid tank; a flow guide cylinder is arranged in the flocculation tank, and a flocculant feeding pipe is arranged at the upper part of the flocculation tank; an inclined pipe and a water outlet collecting tank are arranged in the sedimentation water distribution tank; and a mud bucket and a mud scraper are arranged at the bottom of the efficient sedimentation tank. According to the technical scheme, the crystallization-adsorption-coordination-co-precipitation principle is utilized, fluorine is removed step by step, fluoride is efficiently and stably removed, meanwhile, the sludge yield is reduced, and calcium fluoride crystals can be recycled.

The embodiment of the invention provides a friction material composition, a brake lining, a preparation method of the brake lining, a brake and a vehicle. The friction material composition comprises the following raw materials in parts by weight: 2-10 parts of a fluoride mixture, 8-15 parts of graphite, 8-12 parts of phenolic resin, 4-12 parts of a metal oxide, 15-40 parts of a fiber material and 20-40 parts of other fillers, wherein the fluoride mixture comprises at least two of calcium fluoride, barium fluoride, cerium fluoride, aluminum fluoride, magnesium fluoride, potassium fluoride, sodium fluoride, beryllium fluoride and manganese fluoride. The brake lining prepared from the friction material composition can solve the problems of high wear rate and heat fading at the same time, the service life of the brake lining is prolonged, and the braking effect is improved.

The invention relates to the technical field of cement, and particularly discloses Portland cement and a preparation method thereof.The preparation method comprises the following steps that S1, 70-85 parts by mass of limestone, 10-20 parts by mass of clay, 3-5 parts by mass of iron ore, 3-6 parts by mass of silica fume, 0.8-2 parts by mass of calcium fluoride and 2-4 parts by mass of activated aluminum oxide are smashed and mixed to be uniform, 8-12 parts by mass of pulverized coal and 0.15-0.85 part by mass of a combustion improver are added, and a mixture is obtained; uniformly mixing to obtain a mixed raw material; s2, the mixed raw material is preheated and then calcined, the calcination temperature ranges from 1200 DEG C to 1400 DEG C, the calcination pressure ranges from 800 Pa to 1200 Pa, the calcination time ranges from 30 min to 60 min, cooling is conducted, and the Portland cement is obtained. According to the invention, by optimizing the raw material ratio and calcining in sections, the stability, compressive strength and breaking strength of the cement are effectively improved.

The invention discloses a green roasting method for recycling desulfurized gypsum, and belongs to the technical field of solid waste recycling. According to the process disclosed by the invention, the desulfurized gypsum solid waste rich in calcium sulfate is used for replacing part or all of sulfate to be mixed with lepidolite for roasting reaction, and components such as calcium carbonate and calcium sulfite contained in the desulfurized gypsum are utilized by controlling the step-by-step heating rate and the roasting temperature; under specific roasting process conditions, calcium oxide and calcium sulfide generated through self-reaction serve as purifying agents and react with fluorine and thallium to form stable calcium fluoride and thallium sulfide precipitates, fluorine and thallium are fixed in the high-temperature roasting stage, the pressure of follow-up flue gas treatment and wastewater treatment is effectively reduced through self-purification, and environmental pollution is reduced.

The application discloses a mesoporous carbon preparation process with recyclable silicon source and mesoporous carbon with small pore size and large specific surface area. The mesoporous carbon preparation process comprises the following steps: preparing a silicon template: reacting a fluosilicic acid solution with calcium carbonate, and separating calcium fluoride precipitate and silica sol; the pH of the silica sol is 2-5; the concentration of silicon dioxide in the silica sol is 1-8 wt%; preparing a precursor: dissolving a carbon source and an organic acid in the silica sol, drying, grinding, and carbonizing in an inert atmosphere to obtain a C / Si precursor; the organic acid comprises at least one of oxalic acid, tannic acid, acetic acid and citric acid; removing the silicon template and recycling the silicon source: treating the C / Si precursor with hydrofluoric acid, and performing solid-liquid separation to obtain mesoporous carbon and a fluosilicic acid solution, wherein the fluosilicic acid solution is used for preparing the silicon template. The specific surface area of the mesoporous carbon is greater than 800 m 2 / g, and the pore size is less than 6 nm.

The invention provides a novel lithium extraction method and device for low-grade lepidolite. The novel lithium extraction method for the low-grade lepidolite comprises the following steps: S1, mechanical activation pretreatment: crushing raw ore, treating the crushed raw ore for 2 hours by adopting a planetary ball mill, adding a sodium polyacrylate dispersing agent, and carrying out ultrasonic treatment; according to the novel lithium extraction method and the novel lithium extraction device for the low-grade lepidolite, the specific surface area of the treated mica is increased by 3-5 times, the contact area between the treated mica and assistants and a leachate is greatly increased, the subsequent roasting reaction rate and the lithium leaching efficiency can be improved, the waste of raw materials is reduced, two assistants are matched for segmented roasting, and the cost is reduced. Compared with a traditional process, the roasting temperature is greatly reduced, the energy consumption is greatly reduced, the production energy consumption cost is reduced, calcium fluoride reacts with substances generated in the reaction process (to generate calcium sulfate), fluorine element in-situ fixation is achieved, fluoride dissipation is avoided, the industrial environment-friendly problem of fluorine pollution in the traditional process is solved, and the environment-friendly emission requirement is met.

The application relates to a modified chrome-corundum ramming mixture and a preparation and construction process, and belongs to the technical field of chrome-corundum ramming mixtures. The ramming mixture comprises A material, B material and C material, the A material comprises chrome-corundum aggregates, titanium dioxide-coated alumina microspheres, calcium sulfide dihydrate and porous silicon carbide microspheres; the B material comprises chromium oxide-zirconium oxide composite nano powder, sodium thiosulfate pentahydrate, tricalcium phosphate and hexagonal boron nitride flaky crystals; and the C material comprises an aluminum dihydrogen phosphate-magnesium hydroxide compound, a calcium fluoride-alumina eutectic body and a silane coupling agent. The preparation process comprises pretreatment of components, preparation of composite powder and layered preparation; and the construction process comprises the steps of pretreatment, wet mixing, layered ramming, negative pressure infiltration, medium-temperature reaction, spraying and curing and overall sintering. The application can effectively inhibit the generation of hexavalent chromium, significantly improve the thermal shock resistance, mechanical strength and heat conduction performance of the material, and has the advantages of good environmental protection, long service life, excellent construction performance and the like.

The application provides a tantalum-based alloy and a preparation method thereof. The preparation method of the tantalum-based alloy comprises the following steps: sequentially laying a first mixed material, a second mixed material and magnesium chips in a reaction crucible in a top-down direction, igniting the reaction crucible to generate an aluminothermic reduction reaction, and then sequentially performing a temperature reduction treatment and a surface finishing treatment to obtain the tantalum-based alloy. The first mixed material comprises aluminum particles, tantalum pentoxide, titanium oxide, potassium chlorate and aluminum fluoride. The second mixed material comprises aluminum particles, tantalum pentoxide, titanium oxide, potassium chlorate, aluminum fluoride and calcium fluoride. By adopting double dosing and covering the magnesium chips with the upper material, the application improves the ignition efficiency, significantly improves the material loss caused by the slow ignition speed and insufficient ignition of the material in the traditional off-oven method, and introduces a titanium source to form an AlTaTi compound, thereby significantly enhancing the alloy uniformity.

The invention discloses a treatment process and a treatment system for crystallization of photovoltaic wastewater calcium fluoride sludge, limestone particles and photovoltaic sludge are mixed according to a mass ratio of 3%-5% to obtain a homogeneous mixed material, the homogeneous mixed material is pre-dried and then fed into a rotary kiln, sintering is carried out at 1200-1500 DEG C for 1.5-3 hours, and the sintered material is cooled to room temperature. Calcium fluoride is attached to the surface of the silicate framework, sulfur trioxide and calcium oxide are released at the same time, after sintering is finished, the material is subjected to annealing treatment in a rotary kiln, calcium fluoride seed crystals accounting for 0.1%-1.0% of the total mass of the material are added, calcium fluoride crystals are induced to grow directionally and be repaired, and the calcium fluoride is obtained. According to the method, the purity of calcium fluoride is increased to 75%-85%, the sulfur content in the product can be controlled to be 0.1% or below, and the cold compressive strength of the pellets prepared from the product reaches 2.5 MPa or above.

The application discloses an environment-friendly and efficient solidification and stabilization agent for calcium fluoride sludge and a preparation method thereof, and comprises the following raw materials in parts by weight: a chemical stabilization agent 20-30 parts, an inorganic solidification agent 60-70 parts, a microwave dehydration aid 1-5 parts and a pH regulator 2-5 parts. The application has the advantages of good treatment effect, solves the problems that the existing calcium fluoride sludge treatment agent has poor treatment effect on calcium fluoride sludge in the preparation process, harmful substances and pollutants in the calcium fluoride sludge are easy to penetrate into underground water or soil, environmental pollution is caused, and the treated sludge cannot reach the environmental protection standard and is disposed or utilized, which leads to the problems of re-releasing harmful substances in the use process and forming secondary pollution.

The disclosure provides a method for recycling waste cathode by soluble calcium salt. The method for recycling waste cathode by soluble calcium salt comprises the following steps: S1, screening waste cathode; S2, mixing soluble calcium salt with water to prepare first slurry; S3, mixing first powder and the first slurry, and performing flotation under the assistance of ultrasonic, separating upper flotation foam, and then filtering to obtain first filtrate and first filter residue; S4, performing acid leaching on the first filter residue, and filtering to obtain second filtrate and second filter residue, wherein the second filter residue is calcium fluoride; S5, evaporating the second filtrate to obtain aluminum salt; and S6, evaporating and drying the first filtrate to obtain an alkali mainly containing sodium hydroxide.

The invention discloses a fluorine resource recycling treatment process aiming at alkaline fluorine-containing wastewater, which comprises the following steps: S1, introducing the alkaline fluorine-containing wastewater and calcium salt into a reaction zone, and mixing to generate turbid liquid containing calcium fluoride crystals; s2, carrying out solid-liquid separation on the turbid liquid to obtain an alkaline supernatant, dehydrated calcium fluoride crystals and a separation liquid, and returning the separation liquid to the reaction zone; s3, contacting the dehydrated calcium fluoride crystals with a pickling solution to obtain a mixed solution containing acidic purified calcium fluoride crystals; and S4, neutralizing the acidic purified calcium fluoride crystals in the mixed liquid with alkaline flushing water to obtain a neutral calcium fluoride crystal product and flushing liquid, and outputting the calcium fluoride crystal product. By arranging the pickling zone, the calcium fluoride crystallization product is pickled by using the pickling solution in the pickling zone, so that impurities on the surface of the calcium fluoride crystallization product are removed to achieve a purification effect, and the purity of the calcium fluoride crystallization product is improved.

This invention belongs to the field of glass technology and relates to a high-temperature resistant structural glass material, its preparation method, and its applications. The glass is composed of the following components by mass percentage: 60%-70% silicon dioxide, 5.5%-11% boric acid, 0.1%-5% aluminum hydroxide, 0%-3% potassium nitrate, 5.5%-13% potassium carbonate, 0%-12% sodium carbonate, 0.1%-4% calcium carbonate, 0%-2% calcium fluoride, 0%-1% lithium carbonate, 0%-2% basic magnesium carbonate, 0.1%-1% titanium dioxide, 0%-2% zirconium dioxide, and 0%-1% cerium dioxide; the total mass percentage of potassium nitrate, potassium carbonate, sodium carbonate, and lithium carbonate does not exceed 22%. This structural glass possesses a high softening temperature, a suitable coefficient of thermal expansion, high-temperature resistance, thermal shock resistance, and processing performance, making it suitable as a structural material for optoelectronic devices.

This invention provides a cryo-laser ablation chamber for reflected light fluid inclusions, belonging to the field of geosciences for the analysis of the composition of single fluid inclusions. The device mainly consists of an outer shell, a cryo chamber, an ablation chamber, and a top cover. The cryo chamber, located at the bottom of the outer shell, is made of pure silver, and its top is mirror-polished and connected to a liquid nitrogen tank and pump via a Teflon hose. The ablation chamber, located above the liquid nitrogen chamber, has a standard sample mounting hole. The chamber is spindle-shaped and has inlet and outlet ports at both ends, connected to a carrier gas pipeline. The top cover is equipped with a calcium fluoride glass viewing window, allowing 193nm laser light to pass through. This invention uses a silver cryo chamber to ensure the required cooling effect; simultaneously, the mirror design at the top of the cryo chamber converts the light emitted by the reflected light microscope into transmitted light, thus enabling precise observation and positioning of the fluid inclusions under test without relying on conventional transmitted light systems.

This invention provides a method for producing high-purity aluminum-niobium-tantalum master alloys and co-producing ammonium fluoride, belonging to the fields of metallic materials and inorganic chemicals. The invention involves mixing fluoroniobic acid, fluorotantalic acid, and ammonia water for a precipitation reaction to obtain a precipitate and an ammonium fluoride solution. The ammonium fluoride solution is then concentrated, cooled for crystallization, dehydrated, and dried sequentially to obtain ammonium fluoride. The precipitate is then dried and oxidized and calcined sequentially to obtain an oxide. The oxide, aluminum powder, potassium chlorate, and calcium fluoride are mixed and subjected to a vacuum aluminothermic reaction to obtain the high-purity aluminum-niobium-tantalum master alloy. This invention, considering both broadening the range of raw material selection and optimizing the production process, reacts fluoroniobic acid, fluorotantalic acid, and ammonia water to produce niobium hydroxide and tantalum hydroxide precipitates, which are then oxidized and calcined to form niobium and tantalum oxides. The high-purity aluminum-niobium-tantalum alloy is then prepared using a vacuum aluminothermic reaction. Simultaneously, ammonium fluoride can be co-produced, resulting in high raw material utilization.

This application discloses a high-transmittance ultraviolet fluorescence detection lens, relating to the field of optical lenses. It addresses the problems of insufficient transmittance, severe fluorescence signal attenuation, and poor image quality in existing ultraviolet fluorescence detection lenses. The lens is constructed by sequentially arranging an object surface protection window, a first lens, a second lens, a third lens, an aperture stop, a fourth lens, a fifth lens, and an image plane along the optical axis from the object side to the image side. The object surface protection window is made of calcium fluoride, and at least a portion of the first to fifth lenses are made of calcium fluoride and at least a portion of fused silica. Each lens surface is coated with an ultraviolet antireflection film. By combining calcium fluoride and fused silica to optimize ultraviolet transmittance, and using a multi-layer ultraviolet antireflection film to reduce surface reflection loss, the lens achieves an overall transmittance of over 88% in the 250nm-380nm band. This effectively reduces fluorescence signal attenuation, significantly improves image brightness and contrast, and achieves good aberration correction. The compact structure makes it suitable for mass production applications.

This invention provides a washing system and method for calcium fluoride granules produced through nucleation granulation, comprising a plasma surface activation module, a supercritical fluid extraction washing module, and an intelligent control and circulation module connected in sequence. The plasma surface activation module is used to perform surface modification and impurity weakening treatment on pre-dried calcium fluoride granules. The supercritical fluid extraction purification module is used to deeply remove impurities from the surface and pores of the granules under anhydrous conditions. The intelligent control and circulation module is signal-connected to the aforementioned modules and is used to dynamically regulate the entire purification process based on online monitoring data. The plasma surface activation module includes a vibrating fluidized bed with a reaction chamber, solving the problem of incomplete removal of stubborn surface impurities by traditional water washing. Ultimately, the surface impurity removal rate of the calcium fluoride granules is stabilized at over 95%, and the product purity reaches a high standard for resource utilization.