63results about "Fluosilicic acid" patented technology

A phosphor composition includes a red phosphor material having a red decay rate and a green phosphor material having a green decay rate. The red phosphor material includes a Mn4+ doped phosphor of Formula I and a Eu3+ doped uranium phosphor, and a difference between the red decay rate and the green decay rate is no more than 7 ms, AxMFy:Mn4+ (I), wherein A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Hf, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is an absolute value of a charge of the MFy ion; and y is 5, 6 or 7. A device is also provided.

The invention relates to the technical field of industrial solid waste resource utilization, and particularly discloses a fluorine-containing silicon slag recycling process which comprises five steps of fluorine-containing silicon slag raw material pretreatment, acid leaching fluorine extraction, ammonium fluosilicate preparation, nanometer silica gel purification and wastewater recycling. Fluorine in the fluorine-containing silicon slag is converted into ammonium fluosilicate solid to be recycled, fluorine in the fluorine-containing silicon slag is converted into sodium silicate to be manufactured into nano silica gel to be recycled, only feeding reaction is needed in the whole process, then filtering is conducted, the technological process is simple, and the treatment efficiency of the fluorine-containing silicon slag is improved. 0.3 ton of ammonium fluosilicate (the market price is 8000 yuan / ton) and 0.2 ton of nano silica gel (the market price is 15000 yuan / ton) can be produced from each ton of fluorine-containing silicon slag, and huge economic value can be brought to factories.

The invention belongs to the field of inorganic chemical industry, and particularly relates to a method and a system for efficiently utilizing a phosphate fertilizer byproduct, the method comprises the following steps: carrying out acidolysis on fluosilicic acid with the concentration of more than or equal to 45% wt and concentrated sulfuric acid to generate a mixed solution of silicon tetrafluoride gas and fluorosulfonic acid; the mass ratio of the fluosilicic acid to the concentrated sulfuric acid is controlled to be 1: (4-15); pyrolyzing the obtained fluorosulfonic acid to generate dilute sulphuric acid, hydrogen fluoride and water vapor, forming 98% concentrated sulphuric acid from part of dilute sulphuric acid and fuming sulphuric acid, drying hydrogen fluoride to obtain crude hydrogen fluoride gas, and condensing and rectifying to obtain anhydrous hydrogen fluoride; the rest dilute sulphuric acid is partially compounded and then returned for acidolysis, and the rest dilute sulphuric acid is used for producing white carbon black and flows back to a wet-process phosphoric acid system; and circularly absorbing the obtained silicon tetrafluoride gas by using secondary concentrated fluosilicic acid to obtain fluosilicic acid with the mass concentration of more than or equal to 45%, recycling the fluosilicic acid for acidolysis reaction, and modifying the concentrated by-product silicon dioxide to obtain the high-activity white carbon black. The problems of energy consumption and cost are solved, and efficient circulation and poly-generation of fluorine and silicon resources are achieved in the whole process.

The invention discloses a method for preparing fluosilicate from acidic fluorine-containing wastewater, and belongs to the technical field of wastewater treatment. The method comprises the following steps: carrying out conversion reaction on the acidic fluorine-containing wastewater and a silicon source to obtain conversion reaction clear liquid; adjusting the concentration of the conversion reaction clear liquid by adopting a synthetic reaction clear liquid to obtain a mixed adjusting liquid; carrying out a synthetic reaction on the mixed adjusting solution and a potassium-sodium precipitant solution, and after the synthetic reaction is completed, carrying out solid-liquid separation to obtain a synthetic reaction clear solution and fluosilicate; part of the synthetic reaction clear liquid is used for concentration adjustment, part of the synthetic reaction clear liquid is used for potassium-sodium precipitant solution preparation, and the rest of the synthetic reaction clear liquid enters a subsequent treatment process. According to the method, the acidic fluorine-containing wastewater is used as a raw material, full resource recycling of fluorine elements in the fluorine-containing wastewater is achieved, the synthesis cost of fluosilicate is reduced, and a fluosilicate product which is large in particle size, uniform in particle size, low in water content, high in purity and qualified in quality can be obtained.

The present application discloses a method for wet-process phosphoric acid to recover fluorine, which includes: an acidolysis step: reacting fluorapatite ore powder containing 26%-28% water with concentrated sulfuric acid, maintaining the reaction temperature above 135°C to generate a fluorine-containing gas and a defluorinated slurry containing anhydrous calcium sulfate, wherein the mass fraction of P2O5 in the defluorinated slurry containing calcium sulfate is greater than or equal to 55%, and the fluorine content is 200 ppm to 2000 ppm; an absorption step: absorbing the fluorine-containing gas with an absorption liquid to obtain a fluorine-containing solution, wherein the fluorine in the fluorine-containing solution accounts for more than 95 wt% of the fluorine in the fluorapatite ore powder; a crystal form reconstruction step: performing crystal form reconstruction on the defluorinated slurry containing anhydrous calcium sulfate and filtering to obtain a hemihydrate calcium sulfate filter cake and a filtrate containing phosphoric acid.

The invention relates to a method for preparing high-purity fluosilicate by taking industrial fluorine-containing sludge as a raw material. Comprising the following steps: slurrying calcium fluoride sludge, acidifying with inorganic acid, adding an adsorbent, and filtering; adding soluble salt into the filtrate to carry out crystallization reaction and adjusting the pH value; and cooling, filtering, washing and drying to obtain a target product. Solid waste resource utilization is achieved, the product purity is larger than or equal to 98%, and energy consumption is reduced by 60% or above compared with a traditional process.

The present invention discloses a method for ultra-stable mineralization of beryllium in "artificial fragrant flower stone". The amounts of Ca 2+ , Li + , SiO3 2‑ and F ‑ in the beryllium-containing wastewater or beryllium-containing solid waste slurry are adjusted to an appropriate range for mineralization reaction, so that the free beryllium cations and anions are mineralized into a stable fragrant flower stone [Ca3Li2(BeSiO4)3F2] form, realizing the long-term stabilization of the toxic beryllium element, eliminating the beryllium pollution risk of beryllium-containing wastewater and solid waste, and being particularly suitable for the harmless treatment of beryllium-containing waste generated in the processes of mining, ore dressing, smelting and material processing of beryllium-containing ores such as beryllium ore, lithium ore and fluorite ore. It can make the beryllium content in the wastewater and the beryllium leaching toxicity in the solid waste lower than the national standard, and has the advantages of low cost, no toxicity, simple construction process, high stabilization efficiency, good long-term stability and no secondary pollution.

The present disclosure relates to a method for concentrating fluorosilicic acid from a first liquid stream comprising fluorosilicic acid. In one implementation, the solution comprising fluorosilicic acid and a gaseous stream comprising silicon tetrafluoride is introduced into a first reactor. The first reactor reacts to form the products and separates the products into at least one intermediate gas stream and at least one intermediate liquid stream. The at least one intermediate liquid stream is then introduced into at least one additional reactor. At least one product of the reactor is then separated using the at least one additional reactor. The at least one additional reactor separates the at least one product into at least a final liquid stream comprising fluorosilicic acid. The fluorosilicic acid mass percentage in the at least one final liquid stream is greater than the fluorosilicic acid mass percentage in the at least one first liquid stream.

The present invention relates to the field of water treatment, and discloses a method for resource recycling and reuse of fluorine-containing waste acid and recovery equipment. The equipment includes a fluorine-containing waste acid regulating water tank, a mixing reactor, a fully automatic drum microfilter, an inorganic membrane separation device and a control module. The fluorine-containing waste acid is first pre-treated in the regulating water tank, and then sequentially processed through the mixing reactor reaction, the fully automatic drum microfilter solid-liquid separation, and the inorganic membrane separation device for deep treatment to achieve waste acid resource recycling; the method steps cover the waste acid pretreatment, reaction treatment, solid-liquid separation, and membrane separation treatment links, and are precisely controlled using a sequential control algorithm and a PID control algorithm. The dosage of the reagent and the pressure adjustment are calculated according to specific formulas, respectively, and the influence of historical data is fully considered, so that the treatment process can be controlled more accurately; the invention can efficiently remove fluorosilicic acid impurities, effectively solve the problem of fluorine-containing waste acid treatment, and provide strong support for related enterprises to reduce costs and achieve green production.

The invention relates to the field of water treatment, and discloses a fluorine-containing waste acid resource recycling method and recycling equipment, and the equipment comprises a fluorine-containing waste acid adjusting water tank, a mixing reactor, a full-automatic roller microfilter, inorganic membrane separation equipment and a control module. The waste acid is subjected to reaction in a mixing reactor, solid-liquid separation by a full-automatic roller microfilter and advanced treatment by inorganic membrane separation equipment in sequence, so that the waste acid is recycled; the method comprises the steps of waste acid pretreatment, reaction treatment, solid-liquid separation and membrane separation treatment, and accurate regulation and control are carried out by utilizing a sequence control algorithm and a PID control algorithm. The chemical dosage and the pressure regulation are respectively calculated according to a specific formula, and the influence of historical data is fully considered, so that the treatment process can be more accurately controlled; according to the method, fluosilicic acid impurities can be efficiently removed, the problem of fluorine-containing waste acid treatment is effectively solved, and powerful support is provided for related enterprises to reduce cost and realize green production.

The invention belongs to the field of waste liquid recycling, and discloses a method for preparing potassium fluosilicate by using mixed waste acid, which comprises the following steps: S1, silica fume acidification pretreatment: soaking silica fume in an acid solution for acidification, carrying out precipitation separation on the silica fume, drying, and grinding to obtain acidified silica fume; s2, mixing the raw materials: uniformly mixing the acidified silica fume and the silicon dioxide powder; s3, preparation of fluosilicic acid: adding a mixture of acidified silica fume and silicon dioxide powder into the mixed waste acid, and uniformly stirring by a mechanical stirrer; and S4, preparation of potassium fluosilicate: adding a potassium chloride saturated solution into the fluosilicic acid solution to generate potassium fluosilicate precipitate. The method has the advantages and effects of being high in fluorine ion utilization efficiency, low in production cost and high in finished product purity.

This invention belongs to the field of fly ash treatment technology, specifically disclosing a method for separating potassium and sodium from fly ash, including the following steps: adjusting the acid concentration in the fly ash washing solution to 40-65% and the temperature to 40-65℃, adding a sodium precipitating agent and maintaining the reaction temperature, and filtering to obtain sodium salt and potassium-containing waste liquid. This invention utilizes precipitation to recover sodium ions from fly ash washing solution. After filtration, sodium salt precipitate and potassium-containing waste liquid are obtained. During this process, the reaction is controlled under acidic conditions to prevent potassium ion precipitation. At 40-60℃, the sodium precipitating agent reacts with sodium ions to obtain sodium salt precipitate with large crystals, which allows for more convenient and thorough filtration, resulting in better separation of potassium and sodium ions in the fly ash washing solution. The sodium salt precipitate is further washed with a displacement agent to replace the potassium ions attached to the surface of the sodium salt precipitate with sodium, improving the purity of the sodium salt product. Finally, multiple water washings are performed to reduce the acidity of the sodium salt precipitate, resulting in a sodium salt product with stable quality.

The invention relates to the field of photovoltaic production, in particular to a photovoltaic wastewater treatment method which comprises the following steps: mixing fluorine-containing wastewater with waste acid to obtain fluorine ion wastewater; adding waste silicon dioxide powder into the fluorine ion wastewater to obtain fluosilicic acid wastewater; adding an alkaline sodium source into the fluosilicic acid wastewater to obtain sodium fluosilicate wastewater; and carrying out separation treatment on the sodium fluosilicate wastewater, and extracting bottom-layer jelly to obtain sodium fluosilicate and photovoltaic treatment water. According to the method, waste acid and waste silicon dioxide powder generated in the photovoltaic production process are both utilized, the fluorine content in the wastewater is greatly reduced while no extra chlorine-containing fluorine removal agent is added, fluorine is extracted as a by-product with high purity, photovoltaic wastewater pollution is reduced, the environmental friendliness is improved, and meanwhile, the energy consumption is reduced. The wastewater treatment cost is further reduced, and potential profits are created.

Provided are a liquid dispersion of fluoride particles, which has low viscosity and excellent dispersibility, and is suitable for producing an optical film such as an antireflection film; a method for producing the same; and an optical film using the same. The liquid dispersion of fluoride particles according to the present invention is that in which particles of a fluoride represented by the chemical formula AxCFy (wherein A represents sodium or potassium, C represents silicon or boron, x is 1 or 2, and y is 4 or 6) are dispersed in an aprotic organic solvent having a relative permittivity of 5 to 40, and the optical film according to the present invention is produced by using the liquid dispersion of fluoride particles.

The invention discloses a method for synergistically preparing and purifying sodium fluosilicate by using fluorine-containing waste acid and fly ash. The method comprises the following steps: crushing household garbage incineration fly ash, pulping, pickling, and carrying out solid-liquid separation to obtain crude calcium water; sequentially carrying out heavy metal removal, denitrification, oxidation and neutralization treatment on the crude calcium water, and carrying out solid-liquid separation to obtain refined calcium water; carrying out primary calcium removal treatment on the obtained refined calcium water, and carrying out solid-liquid separation to obtain crude brine; carrying out deep calcium removal treatment on the crude brine to obtain refined brine mainly containing sodium chloride; pretreating the fluorine-containing waste acid to obtain a fluosilicic acid solution; mixing and reacting the fluosilicic acid solution with refined salt water, controlling the pH value of a reaction system to be less than 2, and performing solid-liquid separation to obtain crude sodium fluosilicate; and carrying out multistage countercurrent oxidation washing on the crude sodium fluosilicate, and drying to obtain a sodium fluosilicate product. And resource comprehensive utilization of the fluorine-containing waste acid and the fly ash is realized.

The invention relates to the technical field of chemical raw material production, and particularly discloses a potassium fluosilicate synthesis device and a synthesis method thereof. The device comprises a box body, a feeding mechanism, a mixing mechanism, a multi-stage detection mechanism and an adjusting mechanism. The feeding mechanism realizes accurate proportioning and conveying of fluosilicic acid solution and sylvite solution (such as potassium chloride and potassium sulfate solution) through a plurality of independent conveying pumps. The mixing mechanism adopts a multi-stage disc type reaction tube, a bending part and an inner diameter expansion design, so that fluosilicate (SiF) and potassium ions (K) fully react to generate potassium fluosilicate (K2SiF6) precipitate, and an electric heating tube synchronously regulates and controls the reaction temperature (40-80 DEG C). And the multi-stage detection mechanism performs three-stage pH real-time detection on the slurry through the three detection boxes connected in series and the rotary mixing shaft, so that the detection precision is improved. And dynamically adjusting the pH value to a target range (5.5-6.5) through an acid adding pipe (such as injection of hydrochloric acid) or an alkali adding pipe (such as injection of a sodium hydroxide solution) according to a detection result.

The present invention discloses a method for producing potassium fluorosilicate. The process for generating potassium fluorosilicate in the present invention includes the following steps: 1) Refine fluosilicic acid and place it in a fluosilicic acid storage tank for standby; 2) Dissolve and remove impurities from potassium chloride to obtain a potassium chloride solution; 3) React the refined fluosilicic acid and the potassium chloride solution in a synthesis tank to obtain a potassium fluorosilicate crystal slurry, and then centrifuge and wash it with a centrifuge to obtain potassium fluorosilicate. The production method of potassium fluorosilicate in the present invention is simple, and can reasonably utilize the filtrate and filter residue generated during the production process, reducing the production cost.

This invention discloses a method for separating fluorosilicic acid and hydrofluoric acid using an anion exchange membrane, comprising the following steps: adding a flocculant to a fluorosilicic acid-hydrofluoric acid mixture, aging it, then adding a desulfurizing agent to carry out a desulfurization reaction to obtain a mixed solution, adding the mixed solution to the feed side of an anion exchange membrane for membrane separation, and obtaining a hydrofluoric acid solution with a mass concentration of 2-30% on the clear water side after separation. This invention uses a flocculant to rapidly settle solids such as sodium fluorosilicate and potassium fluorosilicate in the fluorosilicic acid-hydrofluoric acid mixture, uses a desulfurizing agent to remove sulfuric acid, and then uses an anion exchange membrane to effectively separate fluorosilicic acid and hydrofluoric acid in the fluorosilicic acid-hydrofluoric acid mixed solution. The hydrofluoric acid separated by membrane separation has high purity and high output value, increases the utilization rate of by-product hydrofluoric acid, and reduces costs.

The invention relates to the technical field of calcium superphosphate preparation and fluorine resource recycling, in particular to a method for preparing calcium superphosphate and co-producing fluosilicic acid by using wet-process phosphoric acid sludge acid filter residues, which comprises the following steps: carrying out filter pressing on wet-process phosphoric acid sludge acid to prepare clear liquid and acid sludge, and returning the clear liquid to a clear acid tank; acidifying the acid sludge with sulfuric acid and repulping to obtain a mixture A; filtering and washing the mixture A to obtain filter residues B and filtrate C; the filter residue B is subjected to acidolysis again with concentrated sulfuric acid under the conditions of high temperature and negative pressure, gas generated by acidolysis is washed and absorbed to prepare fluosilicic acid D, a solid-liquid mixture E left after acidolysis and the filtrate C are mixed and react with the pretreated phosphate tailings in proportion to obtain a transition product G, and after a curing reaction is conducted at the temperature of 50-60 DEG C, a single superphosphate product H is obtained; a feasible way is provided for comprehensive utilization of the wet-process phosphoric acid sludge and the phosphate tailings, the channel of the superphosphate raw material is widened, and the recycling efficiency of fluorine resources is improved.

The invention discloses a method for preparing fluosilicic acid from yellow phosphorus slag, which comprises the following steps: drying the yellow phosphorus slag, pretreating, and carrying out acidolysis reaction on the pretreated yellow phosphorus slag; solid residues in reactants obtained after the reaction are removed, and filtrate containing fluosilicic acid is obtained; adding sodium sulfide into the obtained filtrate to purify and remove impurities, removing heavy metal ions, adjusting the pH value of the filtrate, and filtering again to obtain purified filtrate; and concentrating the purified filtrate under reduced pressure to separate out fluosilicic acid crystals or directly obtain a fluosilicic acid solution. According to the method disclosed by the invention, resource utilization of the yellow phosphorus slag is realized, accumulation of wastes is reduced, and pollution to the environment is reduced; by optimizing process conditions, the recovery rate of fluorine resources is increased, and the production cost is reduced; in addition, the method is simple in process and suitable for large-scale industrial production, has both technical feasibility and industrial application prospects, and provides important technical support for green transformation of the phosphorus chemical industry.

The invention relates to a semiconductor industry ammonium sulfate solid recycling method, which comprises: (1) mixing a sodium-containing ammonium sulfate solid and an ammonium sulfate solution at a temperature of 60-85 DEG C to obtain a saturated ammonium sulfate solution at a temperature of 60-85 DEG C; (2) carrying out cooling crystallization on the saturated ammonium sulfate solution, and carrying out solid-liquid separation to obtain refined ammonium sulfate and a first mother solution; (3) adjusting the pH value of the first mother liquor to be alkaline, and performing heavy metal impurity removal to obtain impurities and second mother liquor; and recycling the second mother liquor according to the sodium content in the second mother liquor. According to the method provided by the invention, a high-purity ammonium sulfate product can be obtained; and the discharge of mother liquor can be reduced, a sodium fluosilicate byproduct can be produced, the utilization rate of resources is improved, and the economic requirement and the environmental protection requirement are both considered.

The present invention provides a method for recovering fluorine in a wet-process phosphoric acid production process using flash evaporation and cooling coupled with cyclone flow. The method comprises: subjecting a slurry obtained from the acid hydrolysis of phosphate rock to flash evaporation and cooling for crystallization to obtain a flashed slurry; and subjecting the obtained flashed slurry to cyclone separation to recover fluorosilicate particles. The method, provided herein, utilizes flash evaporation and cooling coupled with cyclone separation to separate and recover fluorine from the acid hydrolysis of phosphate rock into large-particle fluorosilicates. The process is simple and easy to operate, and without the need for the addition of any chemical reagents, the method achieves excellent fluorine recovery, with a recovery rate exceeding 32.4%. This method can effectively reduce the fluorine content in phosphogypsum and phosphoric acid produced during the wet-process phosphoric acid production process and facilitates the subsequent recycling of fluorine resources.

The present invention relates to the technical field of water treatment, more specifically, it relates to a kind of resource treatment method of BOE waste liquid, and its technical scheme key points are, comprise the following steps: S1, sodium salt solution is added to BOE waste liquid to react, obtain sodium fluorosilicate and the first waste liquid;S2, aluminum salt solution is added to the first waste liquid, and pH is adjusted to 4-7, and cryolite and the second waste liquid are obtained;S3, defluorinating agent and heavy capture agent are added to the second waste liquid, and the first waste residue and the third waste liquid are obtained;S4, pH of the third waste liquid is adjusted to 2-4, evaporation crystallization is carried out, and evaporation condensation water and concentrated liquid are obtained;S5, the concentrated liquid is pumped into cooling crystallization tank and cooled, centrifuged, and ammonium salt and final mother liquor are obtained;S6, the third waste liquid and the final mother liquor are returned to the S1 and the S2 for circulation. The present invention can realize the resource recovery of components in BOE waste liquid, and has the advantages of obtaining high-value sodium fluorosilicate, cryolite and agricultural grade ammonium salt products.

The application discloses a preparation method and application of ferrous hexafluorosilicate and iron-silicon composite material, and adopts hydrofluoric acid and ferrosilicon alloy to prepare ferrous hexafluorosilicate in one step; the difficulty of the application lies in controlling the content of the hydrofluoric acid and the weight of the ferrosilicon alloy, and regulating a certain proportion to achieve balance; although the hydrofluoric acid is highly toxic, the method can achieve good effects by using a small amount of the hydrofluoric acid, and can adopt the excessive ferrosilicon alloy to minimize environmental pollution and be more friendly to the environment; when the prepared ferrous hexafluorosilicate is used as a negative material of a lithium ion battery, irreversible lithium fluorosilicate can be effectively relieved, thereby being favorable to lithium ion embedding and discharging, better relieving volume expansion caused in the charging and discharging process, maintaining the stability of a pole piece structure, greatly improving the electrochemical performance of the lithium ion battery, improving the specific capacity of the battery, and being capable of well reducing the production cost of the lithium ion.

The present application belongs to the technical field of waste liquid treatment, and particularly relates to a graphite purification waste liquid treatment method and a treatment system. The present application introduces a pre-acid pickling system to utilize waste acid twice, reduces the amount of acid used in the acid pickling process of graphite purification, improves the use efficiency of acid liquid, thereby reducing the cost of the graphite purification process and significantly enhancing the overall economy. The present application also introduces a sodium fluorosilicate production line, effectively realizing the resource utilization of residual fluorosilicic acid and fluorosilicate in waste water. Not only can the operation cost of reagents in the subsequent water treatment process be effectively reduced, but also the produced sodium fluorosilicate can be sold to improve economic benefits. An evaporation crystallization system is used to crystallize and recover valuable salts in waste water. The obtained crystalline salt can be further used as a raw material for other products. The treatment system provided by the present application can realize the resource utilization and recycling of waste acid and waste water, and achieve zero emission.

The invention discloses a method for utilizing de-heavy residue from wet-process phosphoric acid, comprising the following steps: step 1), grinding and finely grinding low-grade phosphate ore; step 2), adding the powdered material in step 1), mixing and placing the mixture in a disc pelletizing machine for pelletizing; heating the dried pellets with conventional yellow phosphorus furnace charge, condensing volatilized arsenic sulfide and lead sulfide through a flue gas heat exchanger, and enriching them to obtain arsenic-lead dust; step 6), raising the furnace temperature in step 5) to 1300° C. to 1600° C., condensing P vapor and SiF4 gas generated by the high-temperature reaction through spraying water, and collecting them; step 7), performing solid-liquid separation of the solid yellow phosphorus collected in step 6) and liquid H2SiF6 to obtain a main product, yellow phosphorus, and a by-product, H2SiF6. The preparation of the pellets according to the invention does not require the addition of an additional binder or sintering, has low energy consumption, and has better effects; the invention can separate and enrich As and Pb elements in the de-heavy residue without causing phosphorus loss, and the arsenic-lead dust can be used as a raw material for lead smelting.

The present invention relates to a metal-ion-doped lithium hexafluorosilicate, a preparation method thereof, a negative electrode sheet, a preparation method thereof, and a lithium-ion battery. Among them, the chemical formula of the metal-ion-doped lithium hexafluorosilicate is Li<subgt;2-x< / subgt;A<subgt;x< / subgt>SiF<subgt;6< / subgt>, where A is a Group I metal and does not include Li, and x is 0.5 - 1.5. The negative electrode sheet includes a current collector, an active material layer attached to the surface of the current collector, and a SEI film made of the Li<subgt;2-x< / subgt>A<subgt;x< / subgt>SiF<subgt;6< / subgt> described above. The Li<subgt;2-x< / subgt>A<subgt;x< / subgt>SiF<subgt;6< / subgt> of the present invention has a large interlayer spacing and a rich pore structure. By using Li<subgt;2-x< / subgt>A<subgt;x< / subgt>SiF<subgt;6< / subgt> to pre-form a SEI film on the surface of the negative electrode sheet, during the cycling process, the rich pore structure and the larger interlayer spacing can better improve the desolvation ability of Li<supgt;+< / supgt>, accelerate the transport of Li<supgt;+< / supgt>, and induce uniform lithium deposition, and then generate a SEI film rich in inorganic substances between the SEI film and the active material layer, further inhibiting the formation of lithium dendrites, improving the cycling stability and service life of the lithium-ion battery, and significantly enhancing the stability and capacity of the negative electrode sheet during fast charging.

The invention discloses a titanium-containing ore separation method and a titanium-containing ore separation system. The separation method comprises the following steps: carrying out fluorination reaction on a fluorinating agent and titanium-containing ore to obtain a fluorinated product; carrying out first-stage sublimation-desublimation treatment on the fluorinated product to obtain a mixture of silicon-containing fluoride and an unreacted fluorinating agent and first-stage sublimation residues; performing second-stage sublimation-desublimation treatment on the first-stage sublimation residues to obtain titanium-containing fluoride and second-stage sublimation residues; and carrying out third-stage sublimation-desublimation treatment on the second-stage sublimation residues to obtain vanadium-containing fluoride and third-stage sublimation residues. According to the separation method provided by the invention, silicon oxide, titanium oxide, vanadium oxide, iron oxide and the like in the ore react with the fluorinating agent to generate a mixture containing various fluorides; and sublimating fluorides corresponding to the elements from a mixture generated by the fluorination reaction at different temperature sections, so as to separate and purify a target product.

The invention discloses a method for recovering fluorosilicate from high-purity quartz sand pickling wastewater, and belongs to the field of fluorosilicate recovery technology. The method of the present invention comprises the following steps: S1 high-purity quartz sand is pickled with hydrofluoric acid (ultrapure);S2 pickling is press-filtered to pickling solution after the pickling is completed to obtain fine quartz sand solid and fluorosilicic acid filtrate;S3 fluorosilicic acid filtrate is stirred and heated up and concentrated and then continues to add inorganic alkali solution for sedimentation, until the mixed solution pH is 7.2-7.5 and stops adding inorganic alkali solution;S4 carries out press-filtration to the mixed solution after sedimentation, collects filter cakes to dryness and obtains fluorosilicate. The fluorosilicate purity obtained by applying this method to reclaim is high and the recovery rate is high, and it is achieved that waste resources can be reused, and environmental protection is achieved, with the characteristics of green environmental protection economy.

The invention discloses a preparation method of phosphorus ore defluorination and low-power-consumption yellow phosphorus. The preparation method comprises the steps of first-stage reaction, batching and balling, second-stage reaction, tail gas purification and electric furnace reduction. The method comprises the following steps: by taking medium-low-grade complex collophanite, phosphoric acid, low-silicon high-calcium phosphorite and calcium carbonate or calcium oxide as raw materials, carrying out a first-stage reaction by regulating the ratio of CaO to P2O5 in a mixture for one time; regulating and controlling the ratio of CaO / P2O5 to SiO2 / CaO for the second time, pelletizing, and calcining to carry out a second-stage reaction. The reaction gas is silicon tetrafluoride, and is used for preparing anhydrous hydrogen fluoride and other fluorine-containing products after being purified; the reaction solid phase is low-fluorine high-grade phosphorite, when the phosphorite is used for preparing yellow phosphorus, the fluorine overflow rate and the dust rate are greatly reduced, the phosphorus reduction rate is obviously improved, and the power consumption of the yellow phosphorus is obviously reduced. The technology is a preferred route for energy conservation and consumption reduction of yellow phosphorus and efficient recovery of fluorine resources; meanwhile, phosphorus, fluorine and silicon elements in the middle-low-grade complex collophanite can be directly utilized in a high-valued mode, and a new route is opened up for efficient utilization of a large amount of low-grade complex collophanite in China.