Chunsheng Yan

Bio: Chunsheng Yan is an academic researcher. The author has contributed to research in topics: Hydrofluoric acid & Sulfuric acid. The author has an hindex of 6, co-authored 27 publications receiving 114 citations.

Preparation of magnesium fluoride

Abstract: The invention relates to a manufacturing method of magnesium fluoride, which takes ammonium fluoride and magnesium chloride as raw materials and comprises the steps as follows: (1) an ammonium fluoride solution whose concentration is 30 to 45 percent and a magnesium chloride solution whose concentration is 25 to 36 percent are added in a reaction kettle at the same time for reaction, and a magnesium fluoride ground-paste is generated; (2) the obtained magnesium fluoride ground-paste is filtered to prepare a magnesium fluoride paste which is cleaned by using hot water the temperature of which ranges from 60 to 70 DEG C; the magnesium fluoride paste is dried for 1 to 2 hours at the temperature ranging from 250 to 400 DEG C after washing, and the finished product of the magnesium fluoride is obtained The manufacturing method adopts the ammonium fluoride instead of hydrofluoric acid, wherein, the ammonium fluoride can be obtained through the ammonolysis by adding ammonia water into fluosilicic acid that is a by-product in the phosphate fertilizer industry; the fluosilicic acid is the deleterious-waste which is the by-product during the phosphate fertilizer production process, has very little purpose, and badly influences the environmental protection; in the manufacturing method, the development and the utilization of the fluosilicic acid greatly relieve the environmental protection pressure of the phosphate fertilizer production and the influences on the surrounding environment; and the cost is lower and the material is easy to get because the fluosilicic acid is the by-product in a phosphate fertilizer factory, thereby lowering the manufacturing cost of the magnesium fluoride

Process for preparing kryocide

Abstract: The invention relates to a method for manufacturing cryolite, which takes fluoride-containing waste residues in electrolytic aluminum industry asa raw material which is processed through fragmentation, floatation, acid dipping and neutralization to obtain the cryolite. The method utilizes the carbon residues or electrolytes which are the wastes generated in the electrolytic aluminium to be processed through working procedures such as fragmentation, floatation, acid dipping, neutralization, etc., so the wastes are changed into the cryolite which can be utilized renewedly, thereby realizing the cyclic utilization of fluorine resource, saving the precious fluorite resource for the country, also being beneficial for the electrolytic aluminium to reduce the self consumption, relieving the environment pollution caused by the piling-up of fluoride-containing waste residues of the electrolytic aluminium, and according with the industrial policy of the country for developing the recycling economy. In addition, impurities such as bitumen carbon granules, graphite carbon, etc. in the reaction process can be used as graphite blocks for sale after being processed. By adopting the method, the manufacturing cost of the cryolite is lowered and the economic benefit is remarkable.

Method for producing aluminun fluoride

Abstract: The present invention relates to process of producing aluminum fluoride with fluorosilicic acid and aluminum hydroxide as material. The process includes the following steps: 1. reacting fluorosilicic acid solution and sodium sulfate for 10-60 min, filtering to obtain solid sodium fluorosilicate and waste sulfuric acid solution to be treated and drained; 2. decomposing aluminum fluorosilicate at 300-800 deg.c for 1-5 hr to produce solid sodium fluoride and silicon tetrafluoride gas; 3. absorbing silicon tetrafluoride gas with water and hydrolyzing, filtering to obtain fluorosilicic acid solution to be returned to the step 1 and solid silica, and washing and drying silica to obtain carbon white; 4. reacting solid sodium fluoride and sulfuric acid, condensing, rectifying to obtain anhydrous hydrofluoric acid and solid sodium sulfate returned to the step 1; and 5. reacting anhydrous hydrofluoric acid and aluminum hydroxide to produce aluminum fluoride product. The process is environment friendly.

Method for preparing aluminum fluoride

Abstract: The present invention relates to process of producing aluminum fluoride with ammonium fluoride or ammonium bifluoride and solid aluminum hydroxide as material. The process includes the following steps: gasifying ammonium fluoride or ammonium bifluoride at high temperature, mixing gaseous ammonium fluoride or ammonium bifluoride and solid aluminum hydroxide in the reaction ratio inside a fluidized bed reactor to react fast at 500-600 deg.c to produce solid aluminum fluoride product, and condensating the mixed gas of ammonia and water vapor the reaction produces to obtain ammonia water. The process is simple, and has low cost and high aluminum fluoride product quality.

Preparation method of lithium hexafluorophosphate

Abstract: The invention relates to a preparation method of lithium hexafluorophosphate. The method comprises the following steps: (1), enabling anhydrous hydrogen fluoride and strong phosphoric acid to react under the protection of inert gas to prepare hexafluorophosphoric acid; (2), adding oleum to the hexafluorophosphoric acid prepared in the step (1) under cooling stirring to prepare phosphorus pentafluoride gas; (3), dissolving high-purity lithium fluoride in an anhydrous hydrogen fluoride solution to form an anhydrous hydrogen fluoride solution containing the lithium fluoride; (4), cooling and guiding the phosphorus pentafluoride gas into the anhydrous hydrogen fluoride solution containing the lithium fluoride, reacting, crystallizing, separating and drying to obtain a pure lithium hexafluorophosphate product; and (5), continuously guiding the unreacted and cooled phosphorus pentafluoride gas to the anhydrous hydrogen fluoride solution containing the lithium fluoride and continuously reacting to obtain a lithium hexafluorophosphate finished product. The phosphorus pentafluoride in the process is cooled to fully react so as to prevent incomplete reacted phosphorus pentafluoride powder from causing environmental-protection pressure.

Estimating Cost and Energy Demand in Producing Lithium Hexafluorophosphate for Li-Ion Battery Electrolyte

Abstract: In this work, the production of lithium hexafluorophosphate (LiPF6) for lithium-ion battery application is studied. Spreadsheet-based process models are developed to simulate three different production processes. These process models are then used to estimate and analyze the factors affecting cost of manufacturing, energy demand, and environmental impact due to greenhouse gas (GHG) emissions. The results indicate that in a facility with a capacity of making 10,000 t per year of LiPF6 the cost of production is around $20 per kg of LiPF6, energy consumption is around 30 GWh per year, and the emission of greenhouse gases in CO2-equivalent gases is around 80 t per day. The impact of change in process and economic parameters on the cost of production, energy demand, and emissions is studied. In addition, a few insights on reducing the cost of production are presented. Finally, the impact of varying LiPF6 costs on the overall cost of a Li-ion battery ($ kWh–1) is presented.

Preparation method of lithium hexafluorophosphate

Abstract: The invention relates to a preparation method of lithium hexafluorophosphate The preparation method comprises the following steps of: (1) distilling to obtain hydrogen fluoride liquid of which the purity is over 9999 weight percent; (2) reacting the high-purity hydrogen fluoride liquid with phosphorus pentachloride to obtain mixed gas of the phosphorus pentafluoride and hydrogen chloride; (3) introducing the mixed gas of the phosphorus pentachloride and the hydrogen chloride into hydrogen fluoride and lithium fluoride, reacting at a certain temperature and under certain pressure to obtain solution of lithium hexafluorophosphate, exhausting hydrogen chloride gas at regular time, and absorbing by using water to prepare byproduct hydrochloric acid; and (4) crystallizing and separating, namely filtering the solution of lithium hexafluorophosphate, delivering filtrate into a crystallizing slot, separating the lithium hexafluorophosphate out at the temperature of between -70 and 80 DEG C,filtering, and performing primary drying and secondary drying to obtain a lithium hexafluorophosphate product, wherein the residual hydrogen fluoride gas is displaced by nitrogen The preparation method has readily available raw materials and is easy to operate, the purity of the obtained lithium hexafluorophosphate product is over 999 percent, the moisture is lower than 10ppm, and the production requirements of lithium ion electrolytic cells are met

Process method for producing fluorine compounds and silicon compounds by cleanly utilizing fluosilicic acid

Abstract: The invention discloses a process method for producing fluorine compounds and silicon compounds by cleanly utilizing fluosilicic acid. The process method comprises the following steps of: preparing fluosilicic acid as a phosphorus chemical by-product into an anhydrous aluminum fluoride product, a sodium fluoride product and a cryolite product, and combining with other industrial waste silicon slags and aluminum slags to prepare a 4A zeolite product. The process method comprehensively utilizes the fluosilicic acid and has high resource recovery rate, wherein the recovery rate of the fluorine element reaches higher than 90 percent. Waste silicon dioxide slags generated in the process can be recycled to produce white carbon black and the 4A zeolite, and a mother liquor, a cleaning solution and waste gas which are generated in the production process are all recycled, thereby the environmental pollution is reduced, and the purposes of zero emission and no pollution are truly achieved, thus the method completely meets the requirement for clean production. The invention has the advantages of advanced production process, good product quality and high value, wherein the fluorine content of the aluminum fluoride is high and between 63-65 percent; the quality index of the obtained white carbon black meets the requirement on the standard of the chemical industry; and the quality of the 4A zeolite product meets the requirements on the national standard and the standard of European and American developed countries.

Method for preparing battery grade lithium fluoride

Abstract: The invention discloses a method for producing battery-grade lithium fluoride, which comprises the following steps: (1) dissolving industrial-grade lithium carbonate in water to prepare a lithium carbonate slurry which contains 10 percent to 30 weight percent of lithium carbonate, introducing CO2 gas into the slurry, controlling the temperature to between 30 and 40 DEG C and carrying out carbonization for 4 to 5 hours, then filtering, wherein the filter cake is the lithium carbonate which is not completely carbonized and trace impurities and used for producing industrial-grade lithium fluoride; and the filter liquor is for later use; and (2) mixing the filter liquor obtained by the step (1) and hydrofluoric acid in a volume ratio of 10-35:1, controlling the temperature to between 70 and 80 DEG C and reacting the mixture for 3 to 4 hours to obtain a lithium fluoride slurry, and then filtering, wherein the obtained filter liquor returns to the step (1) for preparing the lithium carbonate slurry, and the obtained filter cake is a lithium fluoride ointment; and drying the lithium fluoride ointment to obtain the lithium fluoride. The method has the advantages of readily available raw materials, short production technological flow, simple equipment and easy operation; meanwhile, the whole process flow is a circulation system, so the utilization rate of raw materials is high and the environmental pollution is less.

Preparation method of sodium fluoride

Abstract: The invention discloses a preparation method of sodium fluoride. The preparation method comprises the following steps: adding sodium sulfate solution at the mass percentage concentration of 12 to 28 percent into ammonium fluoride solution at the temperature of between 30 and 65 DEG C to generate sodium sulfate precipitate, wherein the ammonium fluoride at the mass percentage concentration of 8 to 50 percent serves as a raw material and the adding speed of the sodium sulfate is 40 to 200 ml/min; reacting for 60 to 130 minutes by controlling the stirring speed to 130 to 400 r/min; performing solid liquid separation to obtain sodium sulfate filter cakes; washing the filter cakes by using deionized water; and drying to obtain the sodium sulfate products. Compared with the prior art, the method has the advantages of using the sodium sulfate as the raw material instead of the conventional sodium chloride, preventing chloride ions from entering a production system, reducing corrosion-resistant requirement of the equipment and saving production cost. The method is simple and practical in process route and provides technological theory support for production of the sodium fluoride in the fluorine chemical industry enterprises.