1459 results about "Fluorhydric Acid" patented technology

The invention relates to a comprehensive utilization method of fluosilicic acid containing hydrogen fluoride, which comprises the following steps: 1) reacting a stock solution containing fluosilicic acid with a potassium fluoride raw material, and carrying out solid-liquid separation to obtain potassium fluosilicate and a hydrofluoric acid solution; 2) reacting potassium fluosilicate with a sodium hydroxide raw material, and carrying out solid-liquid separation to obtain a mixture of a potassium fluoride solution, sodium fluoride and silicon dioxide; and returning the potassium fluoride solution to the step 1) to be recycled as a potassium fluoride raw material. According to the scheme, hydrofluoric acid is prepared from fluosilicic acid containing hydrogen fluoride, sodium fluoride and water glass products are produced at the same time, no other byproduct waste is produced, and the raw material utilization rate is high. And meanwhile, the method has the advantages of low raw material cost, low equipment cost and low energy consumption cost, can generate remarkable economic benefits, and is suitable for popularization and application.

The invention discloses a preparation method and application of a conjugated microporous polymer microsphere filler with a hollow structure, silicon dioxide nanospheres are placed in an organic solvent, after uniform ultrasonic dispersion, 1, 3, 5-triacetylene benzene and 2, 6-dibromo-3-aminopyridine are added, after a catalyst is added, a stirring reaction is carried out in a nitrogen atmosphere to obtain yellow powder, and the yellow powder is dried to obtain the conjugated microporous polymer microsphere filler with the hollow structure. Etching with hydrofluoric acid, cleaning the treated product until the filtrate is transparent and colorless, and drying in vacuum to obtain the conjugated microporous polymer microsphere filler with the hollow structure. Nanoscale holes are formed in the hollow-structure conjugated microporous polymer microsphere filler, so that the hollow-structure conjugated microporous polymer microsphere filler has good heat insulation performance and good heat stability at high temperature, and can be used as a heat-resistant performance enhancing filler.

The invention discloses a purification device for producing electronic-grade hydrofluoric acid, which relates to the technical field of hydrofluoric acid production, and comprises a rectifying tower body, tower plates movably connected in the rectifying tower body at equal intervals, overflow weirs fixedly connected on the tower plates, a rotating speed convenient regulation and control mechanism and a state monitoring feedback mechanism, the follow-up rod and the tower plates installed on the outer surface of the follow-up rod can be driven to synchronously rotate in the rectifying tower body, so that the gas-liquid contact area is increased, the gas-liquid contact time is prolonged, the mass transfer process between gas and liquid phases is promoted, in the rectifying process, the separation efficiency and purity can be improved, impurities in raw materials can be removed more easily, and the product quality is improved. And the rotation of the tower plate can enhance the mixing of the liquid on the tower plate, so that the liquid is more uniformly distributed on the tower plate, the residence time and dead zone of the liquid on the tower plate are favorably reduced, and the separation efficiency is further improved.

The invention discloses a method for continuously producing fluorobenzene, which comprises the following steps: S10) mixing anhydrous hydrogen fluoride and aniline in a tubular reactor to obtain an aniline hydrofluoride mixture; s20) introducing the aniline hydrofluoride mixture into a venturi tube reactor in an inert gas atmosphere, sucking powdered and dried sodium nitrite into the venturi tube reactor in a negative pressure environment formed by the venturi tube reactor, and carrying out a synthetic reaction to obtain a diazonium solution; s30) transferring the diazonium solution into a tubular reactor for pyrolytic reaction to obtain a crude fluorobenzene solution; s40) refining the crude fluorobenzene raw material to obtain fluorobenzene; according to the method disclosed by the invention, the crossing from an intermittent artificial kettle reaction to a continuous reaction is realized, the reaction is sufficient and complete, no 70% hydrofluoric acid mother liquor, no 70% sulfuric acid waste liquor, no high-concentration wastewater and no yellow mud solid waste are produced, a high-quality fluorobenzene product can be continuously prepared in a large batch, and the method has good economic and environmental benefits and a wide market application prospect.

The invention relates to the technical field of metal surface treatment, and discloses a titanium felt surface pickling process which is characterized by comprising the following steps: step 1, pretreating a titanium felt; step 2, preparing a pickling solution, wherein the pickling solution comprises 3-5% (by volume) of hydrofluoric acid, 15-20% (by volume) of nitric acid, 0.5-1% (by mass) of a corrosion inhibitor and the balance of deionized water; 3, acid pickling is conducted, specifically, the pretreated titanium felt is hung in an acid pickling tank through a clamp, it is ensured that the titanium felt is completely immersed in an acid pickling solution, a stirring device is started, the speed is controlled to be 100-200 r / min, the temperature is controlled to be 30-40 DEG C, and acid pickling is conducted for 5-15 min; and step 4, cleaning. The titanium felt surface pickling process has the advantages of being efficient in cleaning, low in damage, environmentally friendly and safe.

The invention discloses a BOE waste liquid treatment method and device. The method comprises the following steps: replacing hydrogen fluoride in BOE waste liquid with sulfuric acid, evaporating, fractionating and recovering hydrofluoric acid, neutralizing evaporated residual liquid with ammonia to obtain a fluorine-containing ammonium sulfate solution, defluorinating with fluorgypsum slurry to obtain a low-fluorine ammonium sulfate solution, and concentrating and crystallizing to obtain an ammonium sulfate product. The BOE waste liquid is treated by adopting the scheme, the bottleneck of the market capacity of ammonium bifluoride is avoided, the hydrofluoric acid product and the ammonium sulfate product with huge market capacity are produced, the value orientation of turning waste into wealth, circular economy and environmental protection is really realized, and the method is suitable for industrial popularization and application.

The invention discloses a method for purifying and recycling hydrofluoric acid waste liquid in the electronic industry, which comprises the following steps: rectifying the hydrofluoric acid waste liquid to remove moisture, performing membrane separation treatment on the material liquid to remove most of metal ions in the material liquid, and performing adsorption treatment on the material liquid to remove a small amount of metal ions in the material liquid. And finally, carrying out membrane separation treatment to remove trace metal ions and particulate impurities in the feed liquid. Through a specific combined process, impurities and metal ions in the hydrofluoric acid waste liquid in the electronic industry are effectively removed, the product reaches the electronic-grade recycling standard, and the resource recycling rate is increased.

The invention discloses an environment-friendly titanium alloy etching solution as well as a preparation method and an etching method thereof, and relates to the technical field of printed circuit board production. The environment-friendly titanium alloy etching solution comprises the following components in percentage by mass: 10-30% of ammonium fluoride, 5-15% of an oxidant, 0.1-1% of a wetting agent, 0.3-1.5% of a stabilizer, 2-10% of an accelerator and 0.5-3% of a lateral erosion inhibitor. The stabilizer is selected from at least one of Tween 20, Tween 40 and Tween 85; and the accelerator is selected from at least one of sodium methylene dinaphthalene sulfonate, sodium dibutyl naphthalene sulfonate and dodecyl benzoate. The environment-friendly titanium alloy etching solution disclosed by the invention can selectively and quickly etch titanium alloy without corroding a copper surface and other metals, so that etching factors are effectively increased, and the problem of lateral erosion of a fine circuit is solved. Meanwhile, ammonium fluoride is used as a main agent of the etching liquid instead of hydrofluoric acid, so that the environmental pollution can be effectively reduced.

The invention provides a waste photovoltaic module high-value recovery process based on pyrolysis and wet purification, which comprises the following steps: carrying out pyrolysis decarburization on a waste photovoltaic module to obtain a glass plate, a crystalline silicon battery piece and a copper-tin soldering strip; the method comprises the following steps of: performing alkaline leaching on a crystal silicon cell to obtain a dealuminized crystal silicon wafer, performing acid pickling on the dealuminized crystal silicon wafer to obtain a silver-removed crystal silicon wafer and a silver leaching solution, and extracting a silver elementary substance from the silver leaching solution; removing impurities from the silver-removed crystal silicon wafer through a hydrofluoric acid solution to obtain a high-purity crystal silicon wafer; recovering a copper strip from the copper-tin soldering strip through a high-temperature smelting reduction method; after fluorine-containing pyrolysis gas generated in the pyrolysis process is subjected to combustion and heat exchange, hydrogen fluoride is removed in a two-stage alkali liquor absorption mode, then washing is conducted, and finally obtained flue gas is discharged. According to the wet purification process, the waste crystalline silicon battery piece can be subjected to high-purity recovery, and the crystalline silicon piece, silver and copper with high purity can be obtained. The hydrogen fluoride is removed by adopting a two-stage alkali liquor absorption method, so that the treatment efficiency of the hydrogen fluoride in the pyrolysis gas is improved.

The invention relates to the technical field of composite resin preparation, and discloses a silicon-molybdenum alloy target material preparation method which comprises the following steps: preparing raw materials, selecting molybdenum powder and silicon powder with the purity not lower than 99.9%, mixing, putting the raw materials into a vacuum mixer, vacuumizing to 0.01-0.1 Pa, stirring for 1-5 hours, carrying out ultrasonic assistance, controlling the temperature to 25-40 DEG C to prevent oxidation, and carrying out a forming process. Filling the mixed powder into a detachable hard alloy mold coated with a 0.05-0.2 mm boron nitride coating, carrying out cold press molding, maintaining the pressure for 5-20 minutes to obtain a biscuit, sintering, putting the biscuit into a vacuum sintering furnace, firstly carrying out microwave-assisted heating, then raising the temperature to 1500-1800 DEG C, introducing trace argon in the later period to regulate and control a structure, carrying out a post-treatment process, carrying out numerical control processing on a sintered target material, carrying out chemical cleaning on the mixed solution of hydrofluoric acid and nitric acid, and finally carrying out vacuum sintering. Performing plasma treatment; and finally, performing vacuum packaging and filling high-purity nitrogen. The raw materials are high in purity and excellent in granularity; uniformly mixing and preventing oxidation; forming and sintering are precisely controlled, and the quality of the target material is guaranteed; the surface performance is improved through post-treatment, packaging is oxygen-proof and moisture-proof, and the target material meets the high-end industry requirement.

The invention belongs to the technical field of photovoltaic wet etching, and particularly relates to a low-concentration hydrofluoric acid composite etching solution and a preparation method and an etching process thereof, and the low-concentration hydrofluoric acid composite etching solution comprises the following components in percentage by mass: 5%-10% of hydrofluoric acid, 2%-5% of an etching additive and the balance of water; wherein the etching additive comprises the following components in percentage by mass: 8%-25% of a strong oxidant, 2%-5% of an etching accelerant, 0.5%-2% of an interface modification and mass transfer accelerant, 0.1%-3% of a product control and stabilizer, 0.1%-2% of an equipment compatible corrosion inhibitor and the balance of water; the strong oxidant is used for oxidizing silicon nitride to form a silicon oxynitride transition layer, the etching accelerant is used for providing HF molecules and HF2-ions, and the product control and stabilizing agent is used for complexing SiF62-ions generated by etching.

The invention discloses a fluoride-free flotation-microbiological leaching-multistage magnetic separation synergistic tailing purification process, which takes mine tailings as raw materials and is realized by the following steps: 1, fluoride-free flotation desliming and impurity removal: replacing hydrofluoric acid with a novel anion collector (fatty acid derivative), and preferentially removing mica and feldspar under the condition that the pH is 2.5-3.5; 2, removing iron and aluminum by microbiological leaching: leaching for 48 hours at the temperature of 35 DEG C by utilizing an acidophilus bacillus ferroxidans bacterial solution, and dissolving Fe2O3 and Al2O3 in a wrapped state; 3, high-gradient magnetic separation refining: removing magnetic minerals through 1.2 T strong magnetic separation, and then separating weak magnetic impurities through 0.8 T weak magnetic separation; the indexes of the final product are as follows: the purity of SiO2 is greater than or equal to 99.9%, the whiteness is greater than or equal to 94% (ISO standard), the content of Fe2O3 is less than or equal to 80ppm, Al2O3 is less than or equal to 1200ppm, and the requirements of electronic grade (IOTA-4 standard) quartz powder are met.

The invention provides a method for detecting oxygen content in copper / copper alloy, and belongs to the technical field of metal component analysis. According to the method for detecting the oxygen content in the copper / copper alloy, the mixed solution of nitric acid, hydrofluoric acid and water is used for cleaning the sample, nitric acid can perform corrosion cleaning on the sample, and when oxide or nitride which is difficult to dissolve by nitric acid exists on the surface of the sample, the oxygen content in the sample is detected by utilizing the characteristic of small molecular radius of hydrogen fluoride. The cleaning agent can rapidly penetrate through a compact metal oxide layer, reacts with metal oxide, destroys and dissolves the metal oxide layer, effectively cleans impurities such as oxide and nitride on the surface of a sample, and is beneficial to improving the accuracy of oxygen content testing. The fluxing agent and the sample are heated and melted together, so that the melting point of copper or copper alloy can be reduced, covalent bonds are destroyed, oxygen release is facilitated, and the detection accuracy is further improved; and the fluxing agent is used, so that the stability of low oxygen content detection is improved, and the detection of lower oxygen content is realized.

The invention provides a system and a process method for co-production of hexafluoropropylene oxide and trifluoroacetic acid, and relates to the technical field of fluorine chemical industry. The system comprises a raw material storage device, a liquid phase oxidation reaction device, a rectifying tower, a hydrofluoric acid absorption tank, a trifluoroacetic acid absorption tank, a process water tank, a hydrofluoric acid concentration detector and a trifluoroacetic acid concentration detector. According to the method, the hydrofluoric acid and the trifluoroacetic acid are co-produced while the hexafluoropropylene oxide is produced, so that complex production processes such as use of non-renewable resources, high raw material price, use of a catalyst for catalysis, addition of an auxiliary agent and the like in the traditional hydrofluoric acid and trifluoroacetic acid production process are avoided; the technology for continuously producing hydrofluoric acid and trifluoroacetic acid, which is simple and efficient in technological process, low in raw material price and free of catalyst catalysis, is developed, and the technology is relatively high in technicality, low in safety risk and suitable for industrial application.

The invention discloses a preparation method and application of a high-nitrogen-doped ordered mesoporous carbon supported copper catalyst, and belongs to the technical field of catalyst preparation. The preparation method comprises the following steps: by taking cane sugar and a copper-nitrogen complex as raw materials, SBA-15 as a template agent and sulfuric acid as a catalyst, carrying out equivalent-volume impregnation, low-temperature heat treatment, 800-900 DEG C high-temperature carbonization and nitric acid / hydrofluoric acid demolding to prepare pyrrole nitrogen enriched or pyridine nitrogen enriched high-nitrogen doped ordered mesoporous carbon with a large specific surface area; the preparation method comprises the following steps: loading a copper species on high-nitrogen-doped ordered mesoporous carbon by adopting an equivalent-volume impregnation method, and reducing at 350-400 DEG C to prepare the high-nitrogen-doped ordered mesoporous carbon loaded copper catalyst. The prepared catalyst is high in nitrogen content, large in specific surface area, high in pyridine nitrogen or pyrrole nitrogen enrichment degree and uniform in copper particle dispersion and shows efficient catalytic performance in methanol oxidative carbonylation reaction, and the highest methanol conversion rate is 9.3%.

The invention provides a process system and a process method for recycling a hexafluoropropylene oxide byproduct high-boiling residue, and relates to the field of fine fluorine chemical industry. The process system comprises a heat exchange device, a tubular pyrolysis reaction device, a carbonyl fluoride-trifluoroacetyl fluoride separation tower, a tubular cracking reaction device, a water washing device and an alkali washing device. According to the method disclosed by the invention, the industrial-grade carbonyl fluoride and trifluoroacetyl fluoride are prepared by catalytically pyrolyzing the hexafluoropropylene oxide by-product high-boiling residue; furthermore, a byproduct high-boiling residue of hexafluoropropylene oxide is subjected to complete catalytic cracking to obtain carbonyl fluoride, and a byproduct industrial hydrofluoric acid can be obtained. According to the process system and the process method, the hexafluoropropylene oxide byproduct is recycled into carbonyl fluoride, trifluoroacetyl fluoride and industrial hydrofluoric acid with high added values, harmlessness and recycling of the hexafluoropropylene oxide byproduct high-boiling residues are achieved, the utilization rate of fluorine atoms is 100%, and the process method is mild in reaction condition, economical and environmentally friendly.

The invention provides a zirconium alloy metallographic specimen preparation method which comprises the following steps: (1) pretreatment: intercepting a specimen, avoiding a heat affected zone, and removing greasy dirt on the surface of the specimen; (2) mechanical grinding, wherein the mechanical grinding comprises step-by-step grinding by using metallographic abrasive paper; (3) chemical polishing: chemical polishing comprises the steps of preparing a chemical polishing solution, soaking the sample in the solution and cleaning and wiping the sample, and the chemical polishing solution comprises nitric acid, hydrofluoric acid, oxalic acid and deionized water which are mixed and placed in a polyethylene container; and (4) post-treatment: placing the sample in a nitrogen protective atmosphere furnace, forming an oxide layer on the surface of the sample, and removing residual oxide particles. According to the method, nitric acid, hydrofluoric acid, oxalic acid and deionized water are mixed and placed in a polyethylene container, and the sample is chemically polished, so that the metallographic test piece of the zirconium alloy can be safely and effectively treated, and observation and analysis of a metallographic structure are guaranteed.

The invention discloses a phosphogypsum leachate-carbonate rock dynamic corrosion reaction analysis method based on numerical simulation, and aims to research a migration-corrosion coupling mechanism of acid leachate in a carbonate rock fracture network. The method comprises the following steps: firstly, acquiring a two-dimensional image sequence of a rock core sample through CT (Computed Tomography) scanning, carrying out operations such as threshold segmentation, membrane enhancement and a light shading algorithm on an image by utilizing AVIZO software, extracting fracture structure parameters and establishing a high-precision three-dimensional model; then, multiple groups of simplified models with different fracture widths are constructed in COMSOL Multiphysics, a Darcy flow field and a solute concentration field are coupled on the basis of the Darcy law and a dilute matter transfer theory, and the dynamic corrosion effect under the multi-field coupling effect is quantitatively represented by setting hydraulic gradient boundary conditions and chemical reaction kinetic parameters; the dynamic corrosion reaction process of calcium ions, hydrofluoric acid, sulfuric acid and phosphoric acid in the ardealite leachate and carbonate rocks with different crack widths is accurately simulated.

The invention discloses a tungsten alloy wire which is composed of a tungsten alloy bus and a self-lubricating composite coating, and the self-lubricating composite coating sequentially comprises a pre-coating and a composite coating from inside to outside. The method has the beneficial effects that on one hand, the tungsten alloy bus is subjected to etching treatment through concentrated hydrochloric acid or hydrofluoric acid, and meanwhile, the pre-plating layer is added, so that the binding force between the electroplated layer and the tungsten alloy wire is enhanced; meanwhile, the lubricating composite coating is prepared by adding solid lubricating particles into the electroplating liquid for composite electroplating, so that the die loss in the drawing process is effectively reduced, and the cost is saved; and on the other hand, a nickel aminosulfonate pre-plating process is changed, and impact nickel is used as a pre-plating bottom layer of the diamond wire, so that the binding force of the grinding composite coating and the diamond wire bus is improved, and the problems of wire breakage or silicon wafer scratching and the like caused by falling of the grinding composite coating in the cutting process of the diamond wire can be prevented.

The invention provides an electronic-grade hydrofluoric acid rectification heat exchange device, and relates to the field of heat exchange devices.The electronic-grade hydrofluoric acid rectification heat exchange device comprises a cold recovery box, the surface of the cold recovery box is provided with a hot backflow pipe and a hot circulation box, a plurality of mass transfer boxes are arranged above the cold recovery box, a plurality of mass transfer bottles are fixedly connected to the interiors of the mass transfer boxes, and the tops of the mass transfer boxes are fixedly connected with a top plate; a plurality of adjusting holes are uniformly formed in the surface of the top plate, adjusting boxes are arranged in the mass transfer boxes, high-corrosion-resistance air bags are symmetrically arranged on the surfaces of the adjusting boxes, adjusting blocks are arranged in the adjusting boxes, rotating pipes are arranged in the mass transfer bottles, and stirring paddles are arranged on the surfaces of the rotating pipes. The efficiency and the stability of the hydrofluoric acid rectification heat exchange device are improved, the adaptability of the device to the production scale and different raw materials is improved, and the energy consumption is reduced.

The invention discloses a preparation method of a lithium cobalt oxide material, the lithium cobalt oxide material and a secondary battery, and belongs to the field of positive electrode materials. The lithium cobalt oxide material which is stable in surface structure and good in cycle performance is prepared through acid leaching, phosphate primary coating and fluorine acid ammonium salt secondary coating of lithium cobalt oxide in sequence. The lithium cobalt oxide reacts with H < + > in the acid solution in the acid leaching process, and active sites are formed on the surface of the lithium cobalt oxide; pO4 < 3-> in the phosphate reacts with active sites in the subsequent primary coating process to form stably combined primary coated lithium cobalt oxide, and the phosphate is distributed on the surface of the lithium cobalt oxide in a dotted manner, so that the corrosion of an electrolyte can be inhibited; in the secondary coating process, NH4 < + > in the ammonium fluoride salt is combined with surface O < 2-> of an uncoated area on the surface of the primary coated lithium cobalt oxide to generate water and ammonia gas, so that a tightly coated fluoride coating layer is formed, and the fluoride coating layer can effectively reduce corrosion of hydrofluoric acid generated by electrolyte decomposition to the positive electrode material, reduce release of oxygen on the surface layer and improve the service life of the positive electrode material. The surface structure of the lithium cobalt oxide material is further stabilized.

A novel additive, an electrolyte, and a lithium ion battery, relating to the technical field of lithium ion batteries. The electrolyte comprises a lithium salt and a non-aqueous solvent for dissolving the lithium salt, the electrolyte further comprises an electrolyte additive, the electrolyte additive comprises a positive electrode film-forming additive and a negative electrode film-forming additive, and the electrolyte additive further comprises a fluoro isocyanate-based pyridazine organic compound. The additive can absorb moisture and hydrofluoric acid in the electrolyte, reduce the dissolution of transition metals, improve the thermal stability of lithium hexafluorophosphate, and maintains the stability of a ternary material under high voltage; a sulfuric acid group on the novel additive can be oxidized by oxygen at a positive electrode, so that the oxygen generated when an LFO lithium supplementing agent is activated is absorbed, the capacity exertion, high temperature cycle and high temperature storage of the LFO lithium supplementing agent are significantly improved, and the DCIR of the battery will not obviously increase, thereby improving the stability of the battery.

The utility model discloses an electronic-grade hydrofluoric acid production system, industrial hydrofluoric acid is input into the system to obtain high-purity electronic-grade hydrofluoric acid, and the system comprises a graphite evaporator, a rectifying tower and a condenser, the graphite evaporator is provided with a feeding pipeline and a condensed water outlet, and the feeding pipeline is used for inputting industrial hydrofluoric acid into the graphite evaporator; a steam pipeline is further arranged on the graphite evaporator, the other end of the steam pipeline is connected with the rectifying tower, the steam pipeline is used for conveying gas heated by the graphite evaporator into the rectifying tower, and the rectifying tower is used for rectifying and separating hydrofluoric acid gas produced by the graphite evaporator; industrial hydrofluoric acid is added into the graphite evaporator to be heated to obtain hydrofluoric acid, then the hydrofluoric acid is fed into the rectifying tower with a certain height to be distilled, backflow is conducted in proportion, the product quality meets the requirement, and continuous production can be achieved through combination of the graphite evaporator and the rectifying tower; liquid hydrofluoric acid is used as a raw material, high risk of anhydrous hydrogen fluoride gas is avoided, and safety of the system is improved.

The invention discloses a tungsten alloy wire and a product and a preparation method thereof, the tungsten alloy wire is composed of a tungsten alloy bus and a self-lubricating composite coating, and the self-lubricating composite coating sequentially comprises a pre-coating and a composite coating from inside to outside. On one hand, the tungsten alloy bus is etched through hydrofluoric acid, and meanwhile, the pre-plating bottom layer is added, so that the binding force between the electroplated layer and the tungsten alloy bus is enhanced. Meanwhile, the lubricating composite coating is prepared by adding solid lubricating particles into the electroplating liquid for composite electroplating, so that the die loss in the drawing process is effectively reduced, and the cost is saved; and on the other hand, a nickel aminosulfonate pre-plating process is changed, and impact nickel is used as a pre-plating bottom layer of the diamond wire, so that the binding force of the grinding composite coating and the diamond wire bus is improved, and the problems of wire breakage or silicon wafer scratching and the like caused by falling of the grinding composite coating in the cutting process of the diamond wire can be prevented.

The invention relates to the technical field of semiconductors and electronic chemicals, and particularly discloses an etching solution for selectively etching silicon nitride and titanium nitride and a preparation method of the etching solution, the etching solution comprises the following components in percentage by mass: 10-45% of phosphoric acid, 1-5% of hydrofluoric acid, 0.5-2.5% of a pH buffer agent, 0.01-1.8% of a solubilizer, 0.1-7% of an etching inhibitor and the balance of water. Wherein the pH buffering agent can effectively stabilize the pH of the etching solution, and the solubilizer can improve the solubility of a solvent in the etching solution, reduce the tension of a solid-liquid phase interface in the solution and promote the transfer rate of interphase substances; the etching inhibitor and metal can form a layer of film on the surface of titanium nitride in a coordination bond mode, and it is guaranteed that silicon nitride and titanium nitride have the high selection ratio. The etching solution provided by the invention can inhibit the etching rate of titanium nitride under the condition of higher etching rate of silicon nitride, and can ensure that the requirement of high selection ratio of silicon nitride and titanium nitride is met.

The invention provides a production method and application of niobium hydroxide in tantalum-niobium hydrometallurgy, and relates to the technical field of tantalum-niobium hydrometallurgy. Tantalum-niobium ore is ground to obtain tantalum-niobium particles; hydrofluoric acid and sulfuric acid are added into the tantalum-niobium particles for a decomposition reaction, and decomposition liquid containing tantalum and niobium is obtained; carrying out acid regulation on the decomposition liquid containing tantalum and niobium, and then extracting with MIBK (Methyl Isobutyl Ketone) to obtain a loaded organic phase containing tantalum and niobium; carrying out acid pickling on the tantalum-niobium loaded organic phase to obtain a tantalum-niobium loaded phase; extracting the tantalum-niobium load phase by using an anti-niobium solution to obtain a fluoroniobic acid solution; adding urea into the fluoroniobic acid solution to carry out neutralization reaction, and filtering to obtain a niobium hydroxide crude product; leaching the niobium hydroxide crude product, and drying after leaching to obtain a niobium hydroxide product; the urea is used as the neutralizer for neutralization, liquid ammonia is not used any more, the production risk is greatly reduced, and the safety production cost is reduced.

The invention relates to the technical field of metal material surface treatment, in particular to a high-cleanliness rust-proof surface treatment process for a double-H control shell, which comprises the following steps: immersing the shell in an aqueous solution containing hydrofluoric acid, citric acid, nano titanium dioxide-graphene composite powder and polyethylene glycol, and performing ultrasonic degreasing activation; then carrying out coupling treatment by using an ethanol solution containing KH-550 silane and hydroxylated carbon nanotubes; then spraying an anti-rust solution containing fluorine-silicon modified epoxy resin and zinc oxide-titanium dioxide core-shell particles, and carrying out gradient curing to form a film; and finally, after argon plasma bombardment, ultraviolet irradiation hole sealing is carried out. According to the process, through multi-step innovative treatment, a composite protective film is formed on the surface of the shell, particulate pollutants are reduced to 5 / cm < 2 > or below, the contact angle is increased to 130 degrees or above, the salt mist tolerance is over 1500 hours, the film layer is thin, the hardness is high, the adhesive force is high, the environment friendliness and economical efficiency are achieved, and diversified industrial requirements can be met.

The invention discloses a method for detecting trace chromium element in copper foil based on ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometer), which comprises the following steps: soaking a lithium battery copper foil in a mixed solution of concentrated nitric acid and hydrofluoric acid for high-temperature digestion, adding a scandium internal standard solution, and fixing the volume to obtain a solution to be detected; preparing a mixed standard solution of chromium element and scandium element with a plurality of concentration gradients, and establishing a standard curve through ICP-OES; and determining the content of the chromium element in the to-be-detected solution according to the standard curve. The lithium battery copper foil is digested through a mixed acid system, concentrated nitric acid provides an acid environment and an oxidation effect, hydrofluoric acid promotes dissolution, it is ensured that the copper foil is completely dissolved, and the digestion efficiency is improved; a scandium internal standard method is introduced, a dynamic background correction mode of ICP-OES is adopted, a scandium internal standard element can correct signal fluctuation in a sample introduction process, dual guarantee is formed by the scandium internal standard element and dynamic background correction, interference of a copper matrix on a Cr spectral line is specifically eliminated, and the trace chromium element detection precision is remarkably improved.

The invention relates to a method for recovering hydrogen fluoride gas, which is used for recovering hydrogen fluoride gas in NF3 produced by an electrolytic method, and the method comprises the following steps: mixed gas discharged from a cathode of an electrolytic bath flows into a gas buffer tank; ammonium hydrogen fluoride in the mixed gas is condensed in the gas buffer tank, the residual hydrogen and hydrogen fluoride flow into the micro-channel unit, the hydrogen fluoride is condensed in the micro-channel unit, the condensed hydrogen fluoride flows back to the gas buffer tank, and the uncondensed hydrogen fluoride and hydrogen flow into the falling film absorption unit; the hydrogen fluoride is absorbed by an absorber in the falling film absorption unit, the hydrogen fluoride is recovered as a hydrofluoric acid solution, and the residual hydrogen and the residual hydrogen fluoride flow into a three-waste treatment pond; and residual hydrogen fluoride in the three-waste treatment tank is completely absorbed. According to the invention, the single-tube parallel micro-channel condenser is adopted as a condensation unit, and the tube diameter is as small as 10-1000 microns, so that the heat exchange area is greatly increased, the hydrogen fluoride gas can be more effectively condensed and recovered, and the recovery efficiency is remarkably improved.

The invention relates to the technical field of photoetching, in particular to an anti-HF photoresist-removing alkali-soluble photoresist and a preparation method thereof. The problems that in the prior art, photoresist is poor in hydrofluoric acid resistance effect, and alkali is difficult to dissolve in the photoresist removing process are solved; the preparation method comprises the following steps: introducing a silicon-oxygen bond to obtain modified phenolic resin, adding a fluorine-containing acrylate monomer to obtain modified acrylate, stirring, dispersing, filtering and removing impurities from the modified phenolic resin, the modified acrylate, propylene glycol methyl ether acetate, a photosensitive substance and an auxiliary agent to obtain a photoresist colloid; stirring and dispersing the photoresist colloid and the modified nano titanium dioxide, and removing impurities to obtain the hydrofluoric acid-resistant degumming alkali-soluble photoresist; rigid silica groups and rigid fluorine-containing groups are introduced, modified nano titanium dioxide is cooperatively used for filling gaps of photoresist resin, the hydrofluoric acid resistance of the photoresist is improved, meanwhile, after acid etching, the resin gaps are used for improving the alkali dissolution rate, and pollutant generation and organic solvent use in the photoresist removing process are reduced.