30 results about "Potassium bicarbonate" patented technology

The invention relates to a composite powder explosion suppressant for suppressing aluminum hydride explosion and a preparation method of the composite powder explosion suppressant, belongs to the technical field of explosion suppressants, and solves the problems of single action mechanism, high required explosion suppression concentration, low efficiency and the like of a traditional explosion suppressant. According to the solution, the composite powder explosion suppressant for suppressing aluminum hydride explosion is prepared through raw material pretreatment, powder mixing and drying in sequence, and the composite powder explosion suppressant is prepared from the following components in parts by mass: 10.2 to 30.2 parts of melamine cyanurate, 20.4 to 40.6 parts of monopotassium phosphate, 15.2 to 25.2 parts of potassium bicarbonate, 8.4 to 13.2 parts of aluminum hydroxide, 6.8 to 11.1 parts of zinc borate, 5.0 to 9.0 parts of fumed silica and 2.0 to 5.3 parts of calcium silicate. The explosion suppressant can act on different combustion areas and combustion stages in the aluminum hydride explosion process, the physical and chemical explosion suppression effects of all the components of the explosion suppressant are fully exerted, and meanwhile, efficient explosion suppression of aluminum hydride explosion can be achieved through the synergistic effect of all the components.

The invention provides a preparation method and application of biomass derived carbon / konjac glucomannan composite flexible aerogel, and relates to the technical field of aerogel. The preparation method comprises the following steps: co-activating potassium bicarbonate and melamine, and pyrolyzing biomass at high temperature to prepare rice husk biochar, dispersing the biochar in an aqueous solution, adding KGM to form composite sol, filling a mold with the composite sol, putting the mold into a refrigerator, pre-freezing overnight, and carrying out vacuum freeze drying to form the biomass derived carbon / konjac glucomannan composite flexible aerogel. The composite flexible aerogel has a high specific surface area and a rich microporous structure, provides a large number of adsorption sites for VOCs molecules, significantly improves the adsorption capacity of the composite flexible aerogel to VOCs, has good compression resilience and excellent flexibility, is slightly influenced by environmental factors in the adsorption process, and has good application prospects. The three-dimensional porous structure is stable, collapse is not prone to occurring, high adsorption performance can still be kept after repeated use, the service life is long, and recycling is convenient.

The application discloses a method and system for recycling dust removal ash of blast furnace manganese iron smelting, and first proposes a technical route for recycling carbon powder, fluorite, manganese fluoride, manganese sulfate, potassium bicarbonate, potassium sulfate, sodium chloride and other valuable resources by water washing of the dust removal ash of blast furnace manganese iron smelting. The water washing slag and washing wastewater of the dust removal ash of blast furnace manganese iron smelting are simultaneously treated in a cooperative manner, the process can be designed according to the characteristics of the washing wastewater and the water washing slag, the multistage recovery of the valuable resources is realized, new impurities are not introduced, and the added value of the recovered resources is improved. In addition, the whole process does not discharge wastewater and waste gas, has high economic value and meets the green and environment-friendly production requirements.

The invention discloses a preparation method of a carbon dioxide slow-release phase change cold storage agent for fruit and vegetable preservation, which comprises the following steps: 1) synthesizing poly (N-isopropylacrylamide) hydrogel, and soaking the poly (N-isopropylacrylamide) hydrogel in a mixed solution to obtain PNIPAM hydrogel loaded with citric acid; (2) synthesizing Sponge hydrogel, and soaking the Sponge hydrogel in a potassium bicarbonate solution to obtain Sponge hydrogel loaded with potassium bicarbonate; and (3) the Sponge hydrogel and the PNIPAM hydrogel are assembled, and the carbon dioxide slow-release phase change cold storage agent is obtained. The two hydrogels are assembled, so that the PNIPAM gel network shrinks when the temperature rises to be higher than LCST in the transportation process, the loaded citric acid solution is diffused into Sponge gel and reacts with KHCO3 to generate CO2, and after the temperature falls back, the reaction is slowed down or stopped, so that the controlled release of CO2 is realized.

The application designs a method for preparing optically active methyl fluoropropionate by using diethylamine sulfur trifluoride, comprising the following steps: fluorination reaction: under the protection of nitrogen, methyl S-lactate is added to a dry reaction kettle as raw material, the kettle temperature is cooled to a first reaction temperature, diethylamine sulfur trifluoride is added dropwise into the reaction kettle, after dropping, the reaction kettle is heated to a second reaction temperature, after the reaction is completed, the reaction mixture is added dropwise into saturated sodium / potassium bicarbonate aqueous solution to obtain R-2-fluoropropionic acid methyl ester; the molar ratio of diethylamine sulfur trifluoride to methyl S-lactate is 1-1.5:1, the method is high in efficiency, low in three-waste amount, short in reaction path, suitable for industrial production, and has economic value.

The present disclosure provides a method for extracting potassium bicarbonate from a mineral mixture. The method includes combining potassium chloride, sodium bicarbonate, and magnesium carbonate trihydrate in an aqueous solution. The aqueous solution is cooled to form Engel's salt comprising potassium bicarbonate magnesium carbonate tetrahydrate. Engel's salt is separated from the aqueous solution and leached with water to produce an aqueous potassium bicarbonate solution and magnesium carbonate trihydrate. The method may further include recycling at least a portion of the magnesium carbonate trihydrate produced from leaching Engel's salt back into the aqueous solution. The aqueous potassium bicarbonate solution can be processed to produce various potassium bicarbonate products.

This invention relates to compositions, particularly aqueous compositions, comprising: (a) guanidine and / or at least one unsubstituted guanidine salt, and (b) one or more carbonate compounds selected from sodium bicarbonate, sodium carbonate, potassium bicarbonate, potassium carbonate, ammonium bicarbonate, and ammonium carbonate. The compositions are characterized in that the weight ratio of component (a) to component (b) is in the range of 1:14 to 54:1, and in each case, the weight ratio is determined based on the content of guanidine and carbonate ions in the entire composition. The invention further relates to industrial products comprising the compositions of the invention, and the use of the compositions for stabilizing aqueous industrial products against microbial invasion.

A method to produce alkali formate includes introducing a catholyte solution to an electrochemical reaction chamber having a cathode, the catholyte solution comprising a mixture of alkali formate and alkali bicarbonate, introducing carbon dioxide into the electrochemical reaction chamber with a cathode, and applying electricity to the membrane to cause formation and output of alkali formate. A method to produce potassium formate, comprising introducing a catholyte solution to electrochemical reaction chamber, the catholyte solution comprising a mixture of potassium formate and potassium bicarbonate, introducing carbon dioxide into the electrochemical reaction chamber, and applying electricity to the membrane to cause formation and output of potassium formate.

This invention discloses a method for preparing a GLP-1R receptor agonist and a method for preparing its intermediates. The method for preparing the GLP-1R receptor agonist and its intermediates comprises a method for preparing a compound of formula I-1, which includes the following steps: in the presence of an inorganic base, a compound of formula I-1-6 and a compound of formula I-1-7 are subjected to a substitution reaction in a solvent to obtain a compound of formula I-1; wherein the inorganic base includes one or more of potassium carbonate, potassium bicarbonate, sodium carbonate, and sodium bicarbonate. This method has the advantages of high yield and low cost in the preparation of GLP-1R receptor agonists and their intermediates, and shows good application prospects.

According to the method, polyethyleneimine is used as a modifier, corncob is used as a biomass carbon source, potassium bicarbonate is used as an opening agent, water is used as a solvent, and the nitrogen-doped biomass charcoal material is obtained through calcination under inert gas and used for acetylene hydrochlorination reaction. The catalyst has high activity and chloroethylene selectivity in a reaction for preparing chloroethylene through acetylene hydrochlorination in a fixed bed, and has great industrial application value. Under the conditions that the reaction mass space velocity is 2.0 ml / g.min, V (C2H2) / V (HCl) is 1: 1.05 and the reaction temperature is 220 DEG C, the acetylene conversion rate can reach 84.7%, and the vinyl chloride selectivity is greater than 99%. Meanwhile, compared with the activity of a non-nitrogen-doped biomass charcoal material and the activity of nitrogen-doped commercial activated carbon, the activity of the nitrogen-doped biomass charcoal material is improved by 38.2% and 30%, and a novel preparation method of the nitrogen-doped biomass charcoal material is provided for acetylene hydrochlorination reaction.

The invention provides a water-based fire extinguishing agent and a preparation method thereof, and belongs to the technical field of fire extinguishing agents. The water-based fire extinguishing agent comprises a component A and a component B, the component A comprises potassium bicarbonate, potassium carbonate, potassium chloride and sodium acetate, and the component B comprises glycerin and water; the water-based fire extinguishing agent disclosed by the invention is clean in components, safe and pollution-free, can exert a remarkable fire extinguishing effect on general fire disasters, oil fire disasters, edible oil fire disasters and other fire disasters occurring in a home environment, and has very good practicability.

The invention provides a potassium-based carbon capture adsorbent, a preparation method and application, the preparation method comprises the following steps: mixing potassium bicarbonate as a potassium source precursor with deionized water to prepare an impregnation liquid, adding a carrier into the impregnation liquid according to a preset loading capacity, and stirring to obtain a carrier mixture; placing the carrier mixture in a drying oven for heating and drying; extruding, rolling and granulating the dried carrier mixture to obtain adsorbent precursor particles with uniform particle size; the adsorbent precursor particles are subjected to high-temperature calcination, so that potassium bicarbonate is decomposed and converted into potassium carbonate, and the potassium-based carbon capture adsorbent is formed. Potassium bicarbonate is adopted as a potassium source precursor, so that the technical problems of poor forming effect and low mechanical strength caused by deliquescence of potassium carbonate are fundamentally solved, and meanwhile, high mechanical strength and excellent CO2 adsorption performance are achieved.

The invention discloses an antibacterial agent, a thermoplastic resin composite material with excellent antibacterial performance and a preparation method of the antibacterial agent, and the preparation method of the antibacterial agent comprises the following steps: dissolving ammonium zinc sulfate, potassium bicarbonate and acetone in deionized water, and carrying out stirring reaction at 40-60 DEG C for 8-12 hours to obtain a solution A; and filtering, washing and drying the solution A, and calcining at 720-780 DEG C to obtain the zinc oxide type antibacterial agent. The antibacterial thermoplastic resin composite material is prepared from the following components in parts by weight: 96.5 to 106.5 parts of thermoplastic resin, 2.5 to 6.5 parts of antibacterial agent and 0.1 to 0.5 part of antioxidant; the antibacterial mechanism of the synthesized zinc oxide type antibacterial agent is that zinc ions can be gradually dissociated, and when the zinc ions are in contact with bacteria, the zinc ions can be combined with active protease in the bacteria to inactivate the active protease, so that the bacteria are killed, and the antibacterial effect is achieved.

The invention provides a potassium sulfate modified binder for casting and a preparation method thereof, and belongs to the field of casting materials. The potassium sulfate modified binder is composed of the following chemical components: 60 to 65% of core-shell structure potassium sulfate coated gamma-alumina microspheres, 12 to 14% of water glass, 2 to 4% of potassium bicarbonate, 1 to 3% of sublimable urea, 8 to 12% of magnesium potassium silicate fiber, 1 to 2% of boric anhydride, 1 to 3% of a siloxane-terminated polyethylene glycol-polypropylene glycol-block copolymer, 2 to 3% of potassium dihydrogen phosphate, 0.5 to 1.0% of gamma-aminopropyltriethoxysilane, 0.3 to 0.8% of citric acid, 0.5 to 1.0% of tartaric acid, and 0.5 to 1.5% of lithium nitrate. Through precise component selection and function collaborative design, the contradiction that the casting binder adaptive to the intelligent casting island is difficult to balance among room-temperature strength, medium-temperature strength, high-temperature stability and cleaning collapsibility is systematically solved.

The invention belongs to the technical field of environment-friendly materials, and particularly relates to a modified activated carbon composite material and a preparation method and application thereof. The invention provides a modified activated carbon composite material. The modified activated carbon composite material comprises an activated carbon matrix and metal salt loaded on the activated carbon matrix, the metal salt comprises potassium bicarbonate, potassium carbonate, sodium citrate and sodium tripolyphosphate. The modified activated carbon provided by the invention is good in acid gas adsorption effect, high in acid gas removal rate, high in removal rate and saturated adsorption capacity, long in protection time, low in preparation cost and high in anti-interference capability.

The invention discloses a preparation method and application of an iron-sulfur co-doped composite carbonaceous catalyst, and belongs to the technical field of nano catalytic materials. According to the method, biomass powder and potassium bicarbonate are mixed, calcined and modified with an H2O2 solution to prepare a porous carbon material with rich active groups, the porous carbon material serves as a carrier, then the carrier, FeSO4. 7H2O dissolved in ethylene glycol and L-cysteine are subjected to a hydrothermal reaction, and the iron-sulfur co-doped composite carbonaceous catalyst of a Fe and S co-doped carbon structure is formed. According to the method, the raw materials are cheap and easy to obtain, the preparation method is simple and convenient, and the prepared iron-sulfur co-doped composite carbonaceous catalyst has efficient degradation performance on phenols and derivatives thereof in water and also has good stability.

The present disclosure includes a multi-fluid kit for three-dimensional printing. The multi-fluid kit can include a fusing agent including water and a radiation absorber that absorbs and converts radiation energy into heat, an acidic agent including water and an acidic component having a pH of about pH 1 to about pH 6.9, and a porosity promoter including water and a porosity promoting compound. The porosity promoting compound can chemically react with the acidic component to generate a gas, and can be selected from sodium bicarbonate, potassium bicarbonate, or a combination thereof.

The invention discloses a potassium intercalation metallic transition metal chalcogenide nano array as well as a preparation method and application thereof. The method for preparing the potassium intercalation metallic transition metal chalcogenide nano array comprises the following steps: taking transition metal disulfide and a potassium source compound as raw materials, and forming the one-dimensional potassium intercalation metallic transition metal chalcogenide nano array on a substrate through chemical vapor deposition; wherein the potassium source compound is selected from one or more of potassium carbonate, potassium bicarbonate, potassium oxalate and potassium sulfate. The potassium intercalation metal transition metal chalcogenide nano array prepared by the method disclosed by the invention is flat in surface and can be used as a material of electrodes such as transistors and the like. According to the method of the invention, the resultant product can be adjusted to produce an ohmic contact or a Schottky contact by changing the composition of the precursor material as a raw material.

The present invention discloses a process for the pretreatment of biomass and an application for energy storage based on the synergistic action of a neutral, low-melting-point solvent and potassium bicarbonate, and in particular comprising the following steps: Step 1: Preparation of the neutral, low-melting-point solvent; Step 2: Pretreatment of wheat straw with the solvent obtained in Step 1 to obtain lignin; Step 3: Enzymatic saccharification of the product obtained in Step 2; Step 4: Production of DES-based lignin-carbon materials. This invention uses a neutral DES as the base solvent and potassium bicarbonate (KHCO₃) as a weak base synergist, with wheat straw being used as the primary raw material. The process is characterized by ease of handling, high practicality, and environmental friendliness without pollution.It synergistically optimizes the high value potential of lignin and delivers energy storage materials with high mechanical strength, superior electrochemical performance and excellent safety.

The present invention provides a hair treatment agent that can suppress the decrease in hair strength (firmness, resilience, resistance to breakage, and combability) caused by dyeing and bleaching treatments, while simultaneously suppressing the generation of unpleasant odors in the hair caused by these treatments. [Solution] A hair treatment agent used in mixture with a second agent containing hydrogen peroxide, comprising a carboxylic acid or a salt thereof and an alkaline agent, wherein the carboxylic acid is tartaric acid, the content of the carboxylic acid or salt thereof is 0.001 to 5% by mass, the alkaline agent is at least one selected from the group consisting of ammonia, diethanolamine, and aminomethylpropanol, and further contains a pH buffer, the pH buffer is a carbonate selected from the group consisting of ammonium bicarbonate, ammonium carbonate, sodium bicarbonate, sodium carbonate, potassium bicarbonate, and potassium carbonate, and the pH is 8.5 to 11.5.

The invention relates to the field of ready-to-eat meat balls, in particular to a preparation method of a high-water-retention ready-to-eat meat ball, which is used for solving the problems that the existing ready-to-eat meat ball usually adopts phosphate for water retention and adopts a chemical preservative for corrosion prevention, so that safety dispute and adverse influence on flavor exist. By adding a proper amount of ingredients with a water-retaining function, such as sodium carbonate, potassium bicarbonate, sodium citrate, modified starch, trehalose, psyllium husk powder, methyl cellulose, hydroxypropyl methyl cellulose and microcrystalline cellulose, the prepared meat balls are compact in structure, and the problem that when traditional meat balls are subjected to high-temperature sterilization, the meat balls are not easy to break is solved. According to the instant meat ball, the problem that water loss of the meat ball affects the mouth feel of a product is solved, the eating mouth feel of the instant meat ball is improved, the composite preservative is added, the antibacterial property and antioxidant activity of the composite preservative can be utilized, under the combined action, the growth of bacteria can be remarkably inhibited, free radicals can be eliminated, oxidation of lipid or protein can be slowed down, and the shelf life of food can be prolonged.

The invention discloses a preparation method and application of composite gel for heavy metal contaminated soil remediation. The method comprises the following steps: treating scaphium scaphigerum powder by using a first multi-element eutectic solvent to prepare a biomass suspension; treating polylactic acid by using a second multi-element eutectic solvent to prepare a polylactic acid suspension; heating, stirring and uniformly mixing the two suspensions, adding a chitosan solution, carrying out ultrasonic emulsification, slowly adding potassium bicarbonate and ammonium bicarbonate, and preparing porous gel in situ; and carrying out functional modification on the gel by using a mixed solution containing dopamine, polyhydric alcohols and the like. According to the invention, habitat sites are provided for microorganisms by regulating and controlling the pore structure of the gel, carbon and nitrogen nutrients are provided for the growth of the microorganisms, and heavy metals in the soil are solidified through the effects of chelation, electrostatic adsorption and the like. The gel prepared by the invention can effectively solidify heavy metals in mining area soil, remarkably improve diversity of soil microbial communities, promote proliferation of functional microorganisms, improve microbial biomass and repair a micro-ecological environment of damaged soil in a mining area.

The application discloses a three-dimensional open porous doped carbon material and preparation and application thereof, and belongs to the technical field of new energy materials. The three-dimensional open porous doped carbon material is prepared by using a heterocyclic polymer as a carbon source and a doping source, double potassium salt (potassium chloride and potassium bicarbonate) as an activator, and acetylacetone salt as a metal source, and through steps of ball milling, high-temperature carbonization, acid pickling and drying. The whole preparation process is simple, no organic solvent is involved, and the process is green and efficient. The obtained product has a high heteroatom doping amount, a high specific surface area, excellent pore size distribution characteristics and excellent electrochemical performance. Based on the special electrochemical nitrate reduction mechanism, when the product is used for electrocatalytic reduction of nitrate to synthesize ammonia, the yield is high, the faradic efficiency is excellent, and the long-time running stability is good. The application is an effective expansion in the field of ammonia synthesis, and can provide a new idea for application of the porous carbon material in the field of electrocatalytic reduction of nitrate to synthesize ammonia.

The invention relates to the technical field of CO2 electrochemical synthesis waste liquid recycling, in particular to a selective salt separation treatment method for potassium formate-potassium bicarbonate mixed wastewater and a separation system of the selective salt separation treatment method. The method comprises the following steps: preheating mixed wastewater of which the total salt concentration is 25-330 g per 100 g H2O and the concentration ratio of potassium bicarbonate to potassium formate is greater than or equal to 0.38, selectively separating out large-particle potassium bicarbonate crystals in a negative pressure evaporation and cooling crystallizer, and enabling the concentration ratio of potassium bicarbonate to potassium formate of cooling mother liquor to be less than or equal to 0.33; and feeding the mother liquor into a potassium formate evaporative crystallization system, and concentrating to deeply separate out high-purity potassium formate. According to the method disclosed by the invention, the non-equilibrium separation interval of the solubility curves of the two salts is actively manufactured and maintained, so that the purity of the potassium bicarbonate and potassium formate crystals meets the industrial grade standard, and the problem of'clamping 'of waste salt recycling in a CO2 electrochemical synthesis route is thoroughly solved.

The application discloses a kind of preparation method and application of nano confined zirconium phosphate biochar composite material, belong to environmental functional material technical field, its steps are: (1) peanut shell is crushed and mixed with potassium bicarbonate, pyrolysis activation is carried out under protective atmosphere, after washing ash with dilute hydrochloric acid, mesoporous biochar carrier is prepared;(2) zirconium oxychloride octahydrate is configured into precursor solution and is introduced into the carrier, and continuous stirring is carried out to promote zirconium ion to be fully diffused and impregnated in the mesoporous channel inside the carrier, (3) add phosphoric acid solution to carry out in-situ precipitation reaction, after washing, dry and obtain composite material.The application utilizes the channel confined effect of carrier, realizes the uniform dispersion of zirconium phosphate active component in the pore of biochar at nanoscale, effectively solves the problem of nano-particle agglomeration.The obtained material has excellent selective adsorption performance for heavy metals in wastewater, and the application process is simple, raw materials are cheap, and has wide application prospect in the field of heavy metal wastewater treatment.

The present disclosure provides a method for extracting potassium bicarbonate from a mineral mixture. The method includes combining potassium chloride, sodium bicarbonate, and magnesium carbonate trihydrate in an aqueous solution. The aqueous solution is cooled to form Engel's salt comprising potassium bicarbonate magnesium carbonate tetrahydrate. Engel's salt is separated from the aqueous solution and leached with water to produce an aqueous potassium bicarbonate solution and magnesium carbonate trihydrate. The method may further include recycling at least a portion of the magnesium carbonate trihydrate produced from leaching Engel's salt back into the aqueous solution. The aqueous potassium bicarbonate solution can be processed to produce various potassium bicarbonate products.

The present invention provides carbonation methods for treating industrial byproduct streams comprising sodium sulfate with one or more carbonation reagents, including but not limited to (i) potassium bicarbonate and / or potassium carbonate; or (ii) carbon dioxide (CO2) and a potassium salt, thereby producing (i) a solid phase comprising one or more potassium sulfate salts and (ii) a liquid phase comprising carbonic acid salts in solution. The one or more potassium sulfate salts comprise potassium sulfate (K2SO4), glaserite, or other sodium potassium sulfate salts. The carbonic acid salts comprise sodium carbonate (Na2CO3) and / or sodium bicarbonate (NaHCO3). The present invention also provides processes for isolating the aforementioned salts from industrial byproduct streams. The present invention also provides cyclical processes for recovering and recycling reagents for producing the aforementioned salts from the industrial byproduct streams and from product streams containing the aforementioned salts.

The invention discloses a dual-biomass-derived nitrogen-oxygen co-doped porous carbon material, a preparation method thereof and a supercapacitor based on the dual-biomass-derived nitrogen-oxygen co-doped porous carbon material, and belongs to the technical field of supercapacitor electrode materials. Lignin and silkworm chrysalis meal are mixed according to the mass ratio of 5: 4 and then soaked in a metal nitrate solution, dried and carbonized; the preparation method comprises the following steps: mixing, melting and polymerizing sodium carbonate, potassium bicarbonate and melamino-formaldehyde resin to obtain a composite activation-doping integrated reagent; uniformly mixing the carbonized product with a composite activation-doping integrated reagent, and performing vacuum drying to obtain a calcined precursor; and sequentially carrying out microwave-assisted gradient activation and supercritical fluid purification to obtain the double-biomass-derived nitrogen-oxygen co-doped porous carbon material. The material prepared by the method has a high specific surface area, a reasonable hierarchical pore structure and high-activity heteroatom sites, is mixed with a binder and a conductive agent to prepare a supercapacitor, and has excellent specific capacitance, rate capability and cycle stability.

The invention provides a compound feed additive containing potassium bicarbonate and valonia tannin, which can effectively improve the problem of loose stool of chickens caused by replacement of soybean meal by corn protein peptide, and does not influence the growth performance of the chickens.

The invention discloses a continuous preparation method of an acyl fluoride compound, according to the continuous preparation method, in the presence of a catalyst, perfluoroolefin with a general formula of R1R2C = CR3R4 and carbonyl fluoride are subjected to an addition reaction to prepare the acyl fluoride compound with a general formula of CFR3R4-CR1R2-COF, R1, R2, R3 and R4 are independently selected from CnF2n + 1, and n is 0-6; the catalyst is a non-loaded body porous catalyst and consists of bicarbonate and hydrofluoride, and the bicarbonate is selected from one or more of lithium bicarbonate, sodium bicarbonate, potassium bicarbonate, cesium bicarbonate, magnesium bicarbonate, calcium bicarbonate, strontium bicarbonate and barium bicarbonate; the hydrogen fluoride salt is selected from one or more of lithium fluoride, sodium fluoride, potassium fluoride, cesium fluoride, magnesium fluoride, calcium fluoride, strontium fluoride and barium fluoride; the mass percentage ratio of the bicarbonate to the hydrofluoride is (0-60%): (40-100%). The method is mild in continuous reaction condition, easy to operate, almost free of byproducts and suitable for continuous production.