479results about "Calcium/strontium/barium fluorides" patented technology

Polycrystalline materials of macroscopic size exhibiting Single-Crystal-Like properties are formed from a plurality of Single-Crystal Particles, having Self-Aligning morphologies and optionally ling morphology, bonded together and aligned along at least one, and up to three, crystallographic directions.

The invention relates to a processing method of stainless steel pickling waste liquid, which is characterized in that the processing method includes the steps that: neutral salt wastewater flows into a neutral reduction cell, and mixed acid pickling waste waters flow into a neutralizing tank; reducing agent is added into the neutral reduction cell, and then the reduced wastewater liquid is put into the neutralizing tank and is mixed with the adjusted mixed acid pickling waste waters, and liquid alkali is added into the neutralizing tank; the separated clear waste liquid removes fluorin ions in a settlement tank; neutralizing liquid is added into a final neutralizing tank to cause the pH value of treatment liquid to adjust to be neutralized wastewater liquid which passes through a sand filter to be discharged. The processing method has the advantages that metal ions and fluorin ions are performed the subsection treatment, and neutralizing agent is changed into the liquid alkali from lime cream, the requirement of reaching the standard of the waste liquid emission is not only achieved, but also the mud quantity produced by a mass of lime cream is greatly reduced, heavy metal mud of a retention pond only contains heavy metal compound, the salts of calcium fluoride and calcium sulphate, etc. are separated from the inclined plate settlement tank during the fluoridation stage, thereby the treatment cost is effectively lowered.

The invention relates to a recycling processing method for a stainless steel processing process wastewater grading precipitation, which comprises the following steps: (1) deslagging and homogenizing acid-washing residual liquid and washing wastewater; (2) adjusting the pH to 4.0-5.5 by a CaCO3 filter bed to generate CaF2; (3) oxidizing Fe<2+> into Fe<3+> by an oxidizing agent to generate sedimentsof Fe(OH)2 and Fe(OH)3; after the Fe(OH)2 , the Fe(OH)3 and the CaF2 are deposited, recovering; (4) carrying out three-level alkali adding coagulation precipitation on the supernatant liquid of an oxidation precipitation pool; adjusting the pH to obtain a Cr sediment in the first-level alkali adding coagulation precipitation; acquiring a Ni sediment in the second-level alkali adding coagulation precipitation; carrying out the third-level alkali adding coagulation precipitation and adding a flocculating agent to remove residual heavy metal ions so that discharge water reaches the standard, wherein the alkali added into a grading reaction precipitation pool is NaOH, Ca(OH)2, CaO or Na2 CO3; (5) regulating the pH of the discharge water of the grading reaction precipitation pool to 6.0-8.0; discharging 0-20 percent of wastewater and filtering residual F<-> and suspended matters of 80-100 percent of wastewater to reach the standard and recycle; and (6) recycling the Cr-Ni metal or the compound thereof from the Cr sediment and the Ni sediment acquired by a third-level coagulation precipitation pool by a recycling device.

The invention provides a method and a device for treating fluorine-containing waste water. In the method, a solid-liquid fluidized bed is used as a crystal reactor; a certain amount of calcium fluoride seed crystal is added into the reactor; the fluorine-containing waste water and a calcium-containing precipitator are delivered into a treatment device of the solid-liquid fluidized bed in a reacting ratio to ensure that fluorinions are precipitated on the surface of the calcium fluoride seed crystal; the prepared sand-shaped calcium fluoride precipitated slurry after precipitation is reclaimed; and primarily treated water is subjected to flocculent precipitation further to meet the emission standard. By adopting the method, most fluorinions can be precipitated in the crystallization and precipitating process in the fluidized bed, the generated sand-shaped calcium fluoride has low content of water and high content of calcium fluoride and can be used as fluorine resources for recycling; and in the flocculent precipitating process of the primarily treated water, the consumption of the fluorescent is low, and the yield of slurry is low. Therefore, the comprehensive cost for waste watertreatment is low.

A system for in-situ generation of fluorine radicals and/or fluorine-containing interhalogen compounds XF_n (wherein X is Cl, Br, or I, and n is an odd integer). Such system comprises a fluorine source, a halogen source for supplying halogen species other than fluorine, a chamber for mixing fluorine with halogen species other than fluorine, and an energy source to supply energy to such chamber to facilitate reaction between fluorine and the halogen species other than fluorine. The chamber may be a semiconductor processing chamber, wherein the in situ generated fluorine radicals and/or fluorine-containing interhalogens are employed for cleaning the processing chamber.

The invention relates to a recycling processing method for wastewater produced by processing stainless steel, which comprises the following steps: after acid-washing residual liquid and washing wastewater are carried out wastewater deslagging, homogenizing; pumping into a CaCO3 filter bed to adjust the pH to 4.0-5.5 and removing F<->; adding an oxidizing agent into discharge water, oxidizing Fe<2+> into Fe<3+> and generating Fe(OH)2 and Fe(OH)3; after the Fe(OH)2, the Fe(OH)3 and CaF2 are deposited, recovering; adopting two-level coagulating sedimentation on supernatant liquid; adding alkali to adjust the pH to 8.0-9.5 in the first level; continuously adding the alkali to adjust the pH to 10.0-11.0 in the second level and adding CaCl2 and a flocculating agent to deposit sludge containing chromium and nickel; adding acid liquor into the discharge water to adjust the pH to 6.0-9.0 and filtering residual F<-> and suspended matters to reach the standard and recover; carrying out dehydration separation on the sludge containing ferrum and the sludge containing chromium and nickel; adding strong acid into the sludge containing chromium and nickel to dissolve; adopting two-level alkali adding coagulating sedimentation on the wastewater of a dissolving pool to obtain a Cr(OH)3 sediment and a Ni(OH)2 sediment or a NiCO3 sediment; carrying out sludge-water separation and recovering to obtain chromium and nickel metal or the compound thereof; and using supernatant liquid and the discharge water of a press filter for homogenization.

The invention relates to a method for recycling high-purity fluorine and phosphorus from a wastewater of phosphogypsum residue field. According to the different reaction conditions of calcium fluoride and magnesium ammonium phosphate, the implementation of the method is divided into two stages: in the first stage of recycling high-purity calcium fluoride: adjusting the pH (Potential Of Hydrogen) value of the wastewater of the phosphogypsum residue field by a sodium hydroxide solution to 3-6 to enable the fluoride ions and calcium ions in the wastewater to be reacted to generate calcium fluoride precipitate, filtering and recycling calcium fluoride; and the second stage of recycling high-purity magnesium ammonium phosphate: adjusting the pH value of the wastewater after the first section of recycling high-purity calcium fluoride by the sodium hydroxide solution to 7.5-9.5, adding a magnesium source and an ammonia source at the same time, generating magnesium ammonium phosphate, magnesium ammonium phosphate analogs or phosphate compounds in a crystalline state in a magnesium ammonium phosphate crystallization reactor, filtering and recycling magnesium ammonium phosphate. The water treated by the method disclosed by the invention has low impurity content and can be directly used as the industrial water and circulating cooling water in a phosphorus chemical production system.

Crystalline scintillator materials comprising nano-scale particles of metal halides are provided. The nano-scale particles are less than 100 nm in size. Methods are provided for preparing the particles. In these methods, ionic liquids are used in place of water to allow precipitation of the final product. In one method, the metal precursors and halide salts are dissolved in separate ionic liquids to form solutions, which are then combined to form the nano-crystalline end product. In the other methods, micro-emulsions are formed using ionic liquids to control particle size.

A manufacturing method for a single crystal of calcium fluoride includes the steps of degassing calcium fluoride powder particles to desorb impurities from surfaces of the calcium fluoride powder particles, preprocessing the degassed calcium fluoride powder particles by fusing the degassed calcium fluoride powder particles in a crucible to obtain a preprocessed product, and re-fusing the preprocessed product in a crucible to grow a single crystal of calcium fluoride.

The invention discloses a method for separating lithium carbonate from electrolyte acidic leachate. The method comprises the following steps of: S1, adding a soluble salt solution to aluminum electrolyte acidic leachate while stirring and heating are performed, monitoring the acidity and the concentration of fluoride ions, and stopping the addition when the pH value is greater than 5 and the concentration of the fluoride ions is less than 0.01 g/L, wherein the soluble salt is one or more selected from MeSO4, MeNO3 and MeCl, and Me is metal which can produce precipitate with F<->; S2, performing filtration on reactants, performing washing and drying on filter residues to obtain a fluoride salt of the metal Me, adding a soluble carbonate solution into the obtained filtrate with stirring andheating, and terminating the reaction when the concentration of lithium ions is less than 0.08 g/L; S3, filter the filtrate, performing washing and drying on the filter cake to obtain lithium carbonate, and performing evaporation, crystallization, washing and drying on the filtrate to obtain inorganic salts. According to the method for separating lithium carbonate from the electrolyte acidic leachate, the reaction process is controlled by controlling the concentration of the fluoride ions and the acidity, so that the lithium ions are separated from other ions, lithium carbonate with high recovery rate is obtained, and meanwhile high-purity fluoride and inorganic salt products are obtained.

The invention relates to the field of wastewater comprehensive utilization, and particularly relates to a comprehensive utilization method of wastewater containing phosphorus and fluorine. The comprehensive utilization method comprises the following steps: carrying out twice neutralization on the wastewater containing phosphorus and fluorine, and controlling the final pH value after each time of neutralization; separating calcium fluoride from wastewater according to the solubility product of calcium fluoride and calcium orthophosphate, so as to enable the main ingredients of wastewater to be calcium orthophosphate and silica gel; separating silica gel by centrifugal separation to obtain a waste liquid containing phosphorus; carrying out secondary neutralization on the waste liquid containing phosphorus to enable the pH value to be 4-7; after generating calcium hydrophosphate, carrying out cooling crystallization treatment; separating calcium hydrophosphate to obtain a clear liquid, so as to realize treatment on wastewater containing phosphorus and fluorine. By adopting the comprehensive utilization method, maximal reutilization of the phosphorus fluorine resource is realized, the by-product silica gel is generated, the product additional value is increased, and the cost of treatment on wastewater containing phosphorus and fluorine is reduced.

A method of selecting suitable laser-stable optical material for making an optical element, especially for transmission at wavelengths under 200 nm, is described. It includes a first pre-irradiation to produce radiation damage, subsequent excitation of induced fluorescence with light at between 350 to 700 nm at least ten minutes after the first pre-irradiation and measurement of induced fluorescence intensities at one or more wavelengths between 550 nm and 810 nm. After the fluorescence intensity measurement a second pre-irradiation is performed with an at least 1000-fold higher energy than in the first pre-irradiation and then induced fluorescence intensities are again measured to determine the increase in the fluorescence intensities. The materials determined to have suitable laser stability are used for making lenses, prisms, light-conducting rods, optical windows and optical devices for DUV lithography, especially steppers and excimer lasers, integrated circuits, computer chips as well as other electronic devices.

The process of producing calciumfluoride with fluorosilicic acid and calcium oxide as material includes the following steps: 1. reacting fluorosilicic acid solution and calcium oxide for 10-60 min, filtering to obtain solid calcium fluorosilicate; 2. decomposing calcium fluorosilicate at 200-600 deg.c for 1-5 hr to produce solid calcium fluoride product and silicon tetrafluoride gas; and 3. absorbing silicon tetrafluoride gas with water and hydrolyzing, filtering to obtain fluorosilicic acid solution to be returned to the step 1 and solid silica, and washing and drying silica to obtain carbon white. The process utilizes fluorosilicic acid as one side product of phosphate fertilizer production as one main material, and has low cost and environment friendship.

The invention relates to a method and system for converting sodium-containing and fluorine-containing compounds in a waste cathode carbon block of an aluminum electrolytic cell. The conversion methodcomprises the step that a conversion agent is used for converting the sodium-containing compound in the waste cathode carbon block of the aluminum electrolytic cell into a fluorine-free soluble sodiumcompound, converting the fluorine-containing compound into an insoluble and harmless mineral fluorine compound and converting a cyanide-containing compound into harmless N2 or NH3 and CO2 in an oxidized manner through a mechanochemical conversion reaction in a conversion mill, and therefore the hazards of fluoride and cyanide in the waste cathode carbon block of the aluminum electrolytic cell arecompletely eliminated. The conversion system comprises a waste cathode carbon block crushing device, a milling device, the conversion mill, a stirred reactor and a solid-liquid separation device which are sequentially connected in series, and the solid-liquid separation device is then directly connected with a concentration or crystallization device and a drying or heat treatment device, and thedrying or heat treatment device is connected to the crushing device. By means of the method and system, the process is simple, mass production is easy, the production cost is low, pollution of three wastes is avoided, and the method and system are environmentally friendly.

The invention discloses perovskite quantum dots and a preparation method thereof. The product is blue, green, yellow and red full-spectrum adjustable fluorescent powder for white-light LEDs (Light Emitting Diodes) suitable for ultraviolet/blue light excitation. By utilizing higher stability of mesoporous hollow CaF2 nanospheres, pre-prepared lead-halogen perovskite quantum dots are adsorbed into the cavities of the CaF2 nanospheres by virtue of the capillary principle, and then, residual solvents are removed under mild conditions so as to finally form the perovskite quantum dots with good stability. The preparation method is simple and fast; furthermore, only one non-polar organic solvent is used, so that the original high fluorescence efficiency of the perovskite quantum dots is well kept; and by combination of traditional rare earth luminescent materials with novel high-efficiency perovskite quantum dots, the obtained product has excellent optical properties and has certain popularization value in solid-phase white-light LEDs for illumination and display.

The invention relates to a resource treatment method for a lithium-rich aluminum electrolyte. The method comprises the following steps: firstly performing heat treatment on the lithium-rich aluminum electrolyte to obtain a product A; performing leaching treatment on the roasting product A with a water-soluble inorganic salt as a leaching agent in water, and performing filtering to obtain a filter residue B and a filtrate B; adding an alkali or an aqueous solution of the alkali to the filtrate B to remove aluminum ions in the filtrate B to obtain a filtrate C; and adding a water-soluble carbonate or an aqueous solution of the carbonate to the filtrate C to make lithium ions in the filtrate C be converted into lithium carbonate precipitation, and then performing filtering to obtain lithium carbonate and a filtrate D. The technical problem perplexing aluminum electrolysis industry of rich and high content lithium in an excess aluminum electrolyte and inefficient utilization of valuable metals is solved, the economic benefit is improved, and stable production of an electrolytic aluminum enterprise is promoted.

This method for processing an electrolyte solution that contains a fluorine compound and an organic solvent comprises: a cleaning step wherein a used battery containing the electrolyte solution is cleaned with a cleaning solvent, thereby extracting the electrolyte solution; a post-cleaning liquid recovery step wherein a post-cleaning liquid obtained in the cleaning step is recovered; a gasification step wherein a volatile component contained in the recovered post-cleaning liquid is gasified at a reduced pressure; a calcium fluoride recovery step wherein a fluorine component contained in a gas that is obtained in the gasification step is recovered in the form of calcium fluoride by causing the fluorine component to react with calcium; and an organic solvent component recovery step wherein the organic solvent component contained in the gas that is obtained in the gasification step is recovered.

The invention relates to a method for producing calcium fluoride by bottom sludge generated during treatment of industrial fluoride-containing wastewater. Calcium fluoride in the bottom sludge is obtained through combination of hydrochloric acid, sodium carbonate and caustic soda and two-time acidification seperation. The method has the advantages of solving the land occupation problem of bottom sludge generated during treatment of industrial fluoride-containing wastewater, effectively utilizing fluorine resources in the bottom sludge and providing calcium fluoride products with utilization value.