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93results about "Product crystals bed crystallization" patented technology

Method for recovering BHET monomer from waste polyester textile alcoholysis solution

The invention provides a method for recovering a BHET monomer from a waste polyester textile alcoholysis solution, and is characterized in that the recovery method comprises the following steps: (1) filtering: mixing the waste polyester textile alcoholysis solution with water under a stirring condition, and filtering at 55-70 DEG C; and (2) cooling crystallization: under a stirring condition, carrying out primary cooling on the filtrate obtained by filtering in the step (1) from 55-70 DEG C to 45-55 DEG C, then adding a BHET seed crystal, then carrying out secondary cooling to 5-15 DEG C, and maintaining the temperature for 20-60 min to obtain the BHET monomer. The mixed solution cooling crystallization method is developed on the basis of complexity of components of the waste polyester textile fabric, the problems that in the conventional production process, a BHET crystal product is low in quality, prone to scaling, difficult to filter and dry and the like are solved, and the obtained BHET product is large in particle size, narrow in particle size distribution, high in purity, good in fluidity and high in stability.
Owner:TIANJIN UNIV

Compositions that contain lipophilic plant material and surfactant, and related methods

Described are liquid compositions that contain a desired (e.g., extracted) plant material such as cannabinoid, terpene, terpenoid, or the like, contained, e.g., dissolved, suspended, or emulsified, in the liquid, which contains surfactant; methods of preparing these types of liquid compositions; and methods of processing this type of liquid composition to collect, isolate, concentrate, or purify a desired target material contained in the liquid composition.
Owner:ZUMPANO MICHAEL V

Use method of 2, 4-dihydroxybenzoic acid dissolving and recrystallizing equipment

The invention discloses a use method of 2, 4-dihydroxybenzoic acid dissolving and recrystallizing equipment, the 2, 4-dihydroxybenzoic acid dissolving and recrystallizing equipment comprises a closed dissolving kettle, a crystallization kettle and a mother liquor storage tank, the closed dissolving kettle, a first separator, a first filtrate storage tank and the crystallization kettle are connected in sequence, and the mother liquor storage tank is connected with a second separator. A discharge port of the crystallization kettle is connected with a feed port of a second separator, a filtrate discharge port of the second separator is connected with a liquid inlet of a second filtrate storage tank, and a liquid outlet of the second filtrate storage tank is communicated with a liquid inlet of the mother liquid storage tank through a third pipeline; the second pipeline between the first separation column and the second pump body is communicated with a liquid outlet of the mother liquid storage tank through a fourth pipeline; the second pipeline between the second pump body and the fourth pipeline is communicated with one end of a backflow pipeline, and the other end of the backflow pipeline is communicated with the first pipeline. The 2, 4-dihydroxy benzoic acid dissolving and recrystallizing equipment disclosed by the invention can be used for preparing 2, 4-dihydroxy benzoic acid with the purity of 99.68%, and the content of metal ions is reduced to 0.15 ppm.
Owner:TIANJIN VOCATIONAL INST

Liquid separation methods

A liquid separation method (10) for separating mono ammonium phosphate ("MAP") (20) in aqueous solution, includes: • a receiving step in which a process liquid which comprises water and MAP is received; • a cooling step in which a controlled cooling process is applied to the process liquid to induce the crystallization (14) of MAP; • a separating step (16) in which the crystallised MAP is separated from the remaining process liquid.
Owner:ARTHUR H VENTURES BV

Method for separating and purifying beta-alanine from fermentation liquor

The invention relates to the technical field of purification of beta-alanine, and discloses a method for separating and purifying beta-alanine from fermentation liquor. The invention provides a method for separating and purifying beta-alanine from fermentation liquor by combining flocculation and resin to overcome the defects that an existing process for separating and purifying beta-alanine from fermentation liquor is tedious in route, high in cost and technology, large in energy consumption and the like. Impurity substances can be effectively removed through the steps of flocculation impurity removal, protein removal, resin adsorption decoloration, resin adsorption elution refining and crystallization extraction of beta-alanine, and the obtained product is high in purity. Meanwhile, the method is simple to operate, mild in process condition and low in cost.
Owner:ZHEJIANG UNIV OF TECH +1

Processing method for fractionation and rapid crystallization of palm oil

The invention discloses a processing method for fractionation and rapid crystallization of palm oil, which comprises the following steps: (1) heating and controlling a palm oil raw material to be fractionated to 55-65 DEG C (crystal breaking), pumping the palm oil raw material into a crystallizing tank, and then cooling the palm oil raw material to about 25 DEG C under the action of rapid cooling of cooling water (or chilled water) and stirring; (2) continuously reducing the temperature of the palm oil raw material in the crystallizing tank by using chilled water, adding a certain proportion of palm oil (solid-liquid mixture) which is completely crystallized and is in an unseparated state into the crystallizing tank at the interval of 25.0-18.0 DEG C as a seed crystal, and controlling the stirring speed of the crystallizing tank at 15-30r / min until the palm oil raw material is completely cooled and crystallized; (3) after crystallization is completed, if seed crystals need to be added into the crystallizing tank which is cooling and crystallizing, pumping the seed crystals into the crystallizing tank which needs to be added with the seed crystals through a pump; otherwise, immediately pumping into a membrane filter for filtering and separating (preventing the tank from being burnt) to obtain liquid oil and stearin. The palm oil seed crystal is added, so that the crystallization time can be shortened; and through seed crystal induction, the formation of stable-form crystals is accelerated, excessive crystallization is avoided, and the interception loss of filtration is reduced, so that the liquid oil yield is improved.
Owner:CHINA GRAIN OIL IND DONGGUAN CO LTD

Method for producing electronic grade nickel sulfate from nickel powder, crystallization apparatus, and method for controlling the crystallization apparatus

Method for producing electronic grade nickel sulfate from nickel powder, crystallization apparatus, and control thereof The present invention provides a method for producing nickel sulfate, and nickel sulfate produced thereby. The process includes acid leaching, copper removal, acid adjustment, concentration, cooling crystallization, drying and sieving, and secondary leaching. Oxidation In the calcination furnace, the temperature is 400 to 700°C, and 1 kg of compressed air is used for each kilogram of nickel powder. ~5m 3 The reaction time is 1.0 to 2.5 hours, and the temperature during acid immersion is controlled to 45 to 70°C. Then, add dilute sulfuric acid to control the pH to 0.5-1.5 and react for 1-3 hours. The copper removal is to replace the copper with nickel powder, and the acid conditioning is to use nickel hydroxide or The pH is adjusted to 2.5-4.5 using nickel carbonate, and the filtrate is concentrated by The cooling crystallization method is to obtain nickel sulfate crystals and return the mother liquor to the concentrate. Drying and sieving is to add the undersieved material to the crystallizer as seed crystals, and secondary leaching is to Dilute sulfuric acid is added to the leaching slag, and it is reacted with nickel sulfate or hydrogen peroxide until nickel is less than 0.1%. If the first stage is full, the second leaching is continued. The crystallizer is a crystallizer that is connected in series with a second-stage crystallizer and a third-stage crystallizer. A crystallization frame, an oscillator provided under the crystallization frame, and an oscillator provided at the exit end of the crystallization frame. The crystallization frame is a rectangular parallelepiped. The bottom of the ribs are evenly spaced, with a cross section of a circular arc. The distance between two adjacent ribs is S is 1 / 25 to 1 / 15 of the width of the crystallization frame, and either the width b or the height h of the rib The width of the crystallization frame is 1 / 100 to 1 / 150 of the width of the crystallization frame. It does not add any new impurity ions, and does not add any oxidizing agent. The nickel sulfate crystal particles produced are uniform and are free of the static generation. This avoids caking of very large particles, irregularly shaped particles and crystals.
Owner:HUNAN JINYUAN NEW MATERIALS CO LTD

Preparation system and method for xylitol crystal

The present disclosure provides a preparation system and a preparation method for xylitol crystals. In the preparation system, outlets of a first centrifuge are connected with an inlet of a hot air drying tank and an inlet of a primary mother liquor storage tank through pipelines, respectively. Outlets of a second centrifuge are connected with an inlet of a second fluidized bed dryer and an inlet of a secondary mother liquor storage tank through pipelines, respectively. An outlet of a dicrystalline sugar dissolution tank is connected with an inlet of a blending tank through a pipeline. An outlet of a tricrystalline sugar dissolution tank is connected with the inlet of the primary mother liquor storage tank. The blending tank is provided with an inlet for a raw material of xylitol hydrogenation solution. An output of an outlet of a first fluidized bed dryer is prepared xylitol crystals.
Owner:ZHEJIANG HUAKANG PHARMA

Method for separating high-purity chlorogenic acid and neochlorogenic acid from stevia rebaudiana chlorogenic acid product based on membrane coupling extraction crystallization

The invention discloses a method for separating high-purity chlorogenic acid and neochlorogenic acid from a stevia rebaudiana chlorogenic acid product based on membrane coupling extraction crystallization. The method comprises the following steps: preparing a first to-be-treated solution by taking the stevia rebaudiana chlorogenic acid product as a raw material; treating the first to-be-treated liquid through an ultrafiltration membrane and a nanofiltration membrane in sequence to obtain a trapped fluid II, concentrating the trapped fluid II, and adjusting the pH value to obtain a second to-be-treated liquid; extracting the second to-be-treated liquid with an ethyl acetate-n-butyl alcohol saturated aqueous solution to obtain a raffinate phase I and an extract phase I; adjusting the pH of the raffinate phase I to obtain a third to-be-treated solution; extracting the third to-be-treated liquid with an ethyl acetate-n-butyl alcohol saturated aqueous solution to obtain a raffinate phase II and an extract phase II; drying the extract phase I, crystallizing, pulping and purifying to obtain high-purity chlorogenic acid; and drying the extract phase II, crystallizing, pulping and purifying to obtain the high-purity neochlorogenic acid. According to the method, membrane separation, solvent extraction and fractional crystallization are coupled, and high-efficiency and high-selectivity separation and purification of chlorogenic acid and neochlorogenic acid in a stevia rebaudiana chlorogenic acid product are realized.
Owner:DONGTAI HAORUI BIOTECHNOLOGY CO LTD

Method of manufacturing a particulate transition metal carbonate material

A method of manufacturing a particulate transition metal carbonate material is described. The method includes mixing a transition metal precursor salt with a second salt in a liquid vehicle. A precipitation reaction is then performed to form a slurry of the particulate transition metal carbonate material in the liquid vehicle. The particulate transition metal carbonate material may find use as seeds in a subsequent precipitation reaction. Methods of manufacturing a particulate precursor materials are also described, including performing a precipitation reaction between one or more transition metal sources in the presence of seed particles in a reaction mixture within a precipitation reaction vessel, to form the particulate precursor material by precipitation onto the surface of the seed particles.
Owner:DYSON TECH LTD

Process for preparing ammonium chloride

A process and a chemical production unit for producing crystalline ammonium chloride in the presence of a crystallization additive are provided, wherein the process comprises the steps a) reacting NH3 and HCl by feeding NH3 and HCl to an aqueous solution of ammonium chloride; b) crystallizing ammonium chloride from the aqueous ammonium solution obtained in step a), and c) separating the crystalline ammonium chloride, wherein energy required in step b) is generated in step a). The crystalline ammonium chloride, obtainable by said process, is suitable as a flavoring agent, as an animal feed additive, as an additive for a cosmetic composition or as an additive for a pharmaceutical composition.
Owner:BASF SE

A production process for producing metallic magnesium and industrial silicon by decomposing serpentine using the hydrochloric acid method.

This invention provides a production process for manufacturing metallic magnesium and industrial silicon by decomposing serpentine using the hydrochloric acid method. [Solution] The present invention provides a method for processing serpentine ore as a raw material using a two-stage countercurrent hydrochloric acid leaching process. The wet process steps include storage and filtration of the slurry after ore dressing, two-stage hydrochloric acid leaching under atmospheric pressure, washing and filtration of the silicon slag after leaching, removal of iron and nickel precipitation from the leaching solution, separation, washing and filtration of the obtained iron hydroxide and nickel hydroxide, crystallization and evaporation of the magnesium chloride solution, and production of hydrochloric acid using the gas generated after the thermal decomposition of magnesium chloride. The present invention has developed a serpentine decomposition technology using hydrochloric acid, a metallic magnesium production process using a drying-electrolytic method, and a process for producing industrial silicon by smelting silicon slag in an electric furnace.
Owner:TOLI COUNTY ZHONGDA MAGNESIUM IND CO LTD

Method for rapidly solidifying aluminum isopropoxide

The invention relates to the technical field of metal alkoxide preparation, and particularly provides a method for rapidly solidifying aluminum isopropoxide, which comprises the following steps: concentrating liquid aluminum isopropoxide in vacuum at 80-90 DEG C until the concentration is greater than or equal to 95%; sequentially adding 0.1 to 0.2 percent of a crystallization assisting solvent TXIB, 0.05 to 0.1 percent of a nanoscale aluminum isopropoxide seed crystal and 0.01 to 0.1 percent of a magnesium isopropoxide eutectic seed crystal; crystallization is completed through gradient cooling, and the whole process is less than or equal to 24 hours; and finally, carrying out solid-liquid separation, washing and drying to obtain the high-purity aluminum isopropoxide crystal. Through the synergistic effect of the bifunctional seed crystal and the TXIB, the crystallization period is remarkably shortened, the crystal quality is improved, and the method is suitable for industrial production.
Owner:YANGZHOU ZHONGTIANLI NEW MATERIAL

A process for the preparation of high purity trans-4-propionylcyclohexylbenzene

The application discloses a preparation method of high-purity trans-4-propionylcyclohexylbenzene, and belongs to the technical field of liquid crystal material preparation. The method is based on dynamic synergy of three-stage gradient temperature control, seed addition in batches and intermittent stirring, and in a single petroleum ether solvent system, crystal growth is induced through ultralow-temperature cyclic crystallization and precise temperature control; in combination with a matching filter-drying integrated machine, continuous operation of low-temperature solid-liquid separation and vacuum drying is realized. The application significantly improves the purity and yield stability of the product, and one-time high-purity crystals are obtained, overcoming the problems of incomplete impurity separation, high energy consumption and large batch fluctuation in the traditional process, and simultaneously adapting to the industrial production demand, and providing a green and efficient high-purity preparation path for liquid crystal intermediates.
Owner:SHANDONG QIYANG PHOTOELECTRIC TECH CO LTD

A production method for improving the content of anthracene and carboline in crude anthracene product by using crystal nucleus seed

This invention belongs to the technical field of anthracene oil processing and production, and discloses a production method for increasing the anthracene and carbide content in crude anthracene products using crystal nucleus seeds. The method mainly involves cooling the heated raw anthracene oil to 75°C, then adding high-quality crystal nucleus seeds (70% anthracene content, 17% carbide content, and ≤1% mechanical impurities) to a crystallization tank at a mass ratio of 1:75. At this point, the high-quality crystal nucleus seeds promote the formation of new crystal nuclei in the anthracene oil liquid. As the temperature decreases, the newly formed crystal nuclei gradually grow. Simultaneously, the temperature is naturally lowered to below 65°C through stirring, and the cooling system in the crystallization tank is activated to further cool the temperature to 35-40°C. The mixture is then repeatedly fed and dried in a centrifuge to produce high-quality crude anthracene. This invention utilizes unique high-quality crystal nucleus seeds to achieve an anthracene content of over 40% and a carbide content of over 14% in crude anthracene even when the anthracene and carbide content in the raw anthracene oil is low or unstable, resulting in a superior-grade crude anthracene product.
Owner:SHANXI XINHAIXIANG NEW MATERIAL CO LTD

Sulphate removal using fluidized bed reactor

A process for treating fluids for the removal of sulphate therefrom, the process comprising passing a fluid containing a sulphate and carbonate through a fluidized bed reactor; and, loading sulphate to said fluidized bed reactor at a rate that is greater than 1 kg of sulphate per square metre of said fluidized bed reactor per hour (kg SO4 / m2 / hr); thereby co-precipitating the sulphate and carbonate. The process must maintain the supersaturation levels of calcium sulphate within a predefined range of 100-450% and provides a loading rate of sulphate in the reactor that is greater than 1 kg of sulphate per square metre of reactor per hour (kg SO4 / m2 / hr).
Owner:IDE WATER TECH LTD

Method for initiating crystallization by means of plasma and crystallization generator

The invention relates to a method for initiating the crystallization of a solute present in a solution (S) at a concentration that makes it metastable, comprising the application of one or more plasma pulses to the solution (S).
Owner:CENTSUPELEC

Methods for preparing cannabinoids

The pharmaceutical industry is highly regulated to ensure the safety, efficacy, and quality of medicines, and discoloration of medicines is one of the major causes of drug recalls. It is an object of the present invention to provide an improved method for producing stable, substantially pure cannabinoids for use in medicines. The use of such stable, substantially pure cannabinoids in medicines will improve patient compliance with medication. The main steps of this method are decarboxylation, extraction, winterization, and crystallization.
Owner:JAZZ PHARM RES UK LTD

Preparation system for compound crystals of erythritol and high-intensity sweeteners and method therefor

Systems and methods for preparing compound crystals of erythritol and high-intensity sweeteners are provided. The systems may comprise a fermentation liquid storage tank (1), a ceramic membrane filtration system (2), a nanofiltration system (3), a first evaporator (4), a first crystallization kettle (5), a first centrifuge (6), a sugar dissolution tank (7), a decolorization tank (8), an ion exchange column (9), a blending tank (10), a second evaporator (11), a second crystallization kettle (12), a second centrifuge (13), a hot-air drying tank (14), a fluidized drying bed (15), and a finished product tank (16) sequentially connected through pipelines. The systems may further comprise a high-intensity sweetener storage tank (17), a primary mother liquor tank (18), and a secondary mother liquor tank (19). The finished product tank (16) may store a prepared compound crystallization product of the erythritol and the high-intensity sweetener.
Owner:ZHEJIANG HUAKANG PHARMA

Methods for recovering organic acids or salts or lactones thereof from aqueous solutions using water solvent crystallization and compositions thereof

Compositions and methods are provided for producing crystalline forms of organic acids or salts or lactones thereof from an aqueous solution. More specifically, methods are provided for producing a crystalline form of a salt of mevalonic acid (also referred to as X-MVA) from an aqueous solution, comprising subjecting the aqueous solution comprising said X-MVA to a purification step to produce a purified solution and crystallizing said X-MVA from said purified solution by water solvent crystallization. Methods are also provided for producing mevalonolactone from an aqueous solution comprising X-MVA, comprising subjecting the aqueous solution comprising said X-MVA to cation exchange thereby converting said aqueous solution comprising X-MVA to an aqueous solution comprising mevalonolactone (MVL). Methods are also provided for producing mevalonolactone monohydrate crystals.
Owner:DANISCO US INC

Large particle size sodium nitrate multi-stage flash cooling crystallization production system and production process

ActiveCN118892666BDistillation regulation/controlChemical industryMulti-stage flash distillationPhysical chemistry
The present application relates to a kind of large particle size sodium nitrate multistage flash cooling crystallization production systems, it includes feed unit, evaporation unit, seed unit, flash crystallization unit, condensation unit, thickening unit, centrifugal drying unit and mother liquor reflux unit, seed unit includes material pump and seed tank, the discharge port of separator is connected to seed tank by material pump;Flash crystallization unit includes first flash crystallization ware, first material pump, second flash crystallization ware, second material pump, third flash crystallization ware and third material pump, the discharge port of seed tank is connected to the feed port of first flash crystallization ware, first flash crystallization ware, second flash crystallization ware, third flash crystallization ware are sequentially connected.The sodium nitrate solution of the present application is distributed uniformly by multistage flash, crystal growth time, and crystal size is adjusted by controlling fine crystal elimination amount, crystal size is large, particle size distribution is uniform, crystal size D90≥0.9mm, variation coefficient CV≤25.
Owner:SHANGHAI ZHONGTENG ENVIRONMENTAL PROTECTION TECH CO LTD

Method for simultaneously preparing high-content isochlorogenic acid A and high-content isochlorogenic acid C

The invention discloses a method for simultaneously preparing high-content isochlorogenic acid A and high-content isochlorogenic acid C. The method comprises the following steps: dissolving a stevia rebaudiana polyphenol product in purified water, and adjusting the pH value to obtain a treating fluid 1; adsorbing the treating fluid 1 through macroporous adsorption resin, jacking the treating fluid 1 through purified water, and mixing effluent liquid during adsorption and purified water jacking to obtain effluent liquid 1; concentrating the effluent 1 by using a reverse osmosis membrane, adjusting the pH value to obtain a treating fluid 2, and extracting the treating fluid 2 by using an ethyl acetate saturated aqueous solution to obtain a raffinate phase I and an extract phase I; adjusting the pH value of the raffinate phase I, and extracting with an ethyl acetate-n-butyl alcohol saturated aqueous solution to obtain a raffinate phase II and an extract phase II; after drying the extract phase I, sequentially crystallizing and recrystallizing to obtain high-purity isochlorogenic acid C; and drying the extract phase II, and sequentially crystallizing, pulping and purifying to obtain the high-purity isochlorogenic acid A. The method comprises the following steps: removing impurities by adopting macroporous adsorption resin, extracting by adopting a solvent step by step, carrying out crude separation on the isochlorogenic acid A and the isochlorogenic acid C, and carrying out subsequent crystallization and refining to obtain the high-content isochlorogenic acid A and the high-content isochlorogenic acid C.
Owner:DONGTAI HAORUI BIOTECHNOLOGY CO LTD

Crystalline forms of picolinamide fungicide compound

The present technology relates to processes useful for making crystalline S)-1, 1-bis(4-fluorophenyl)propan-2-yl (3-acetoxy-4-methoxypicolinoyl)-Lalaninate Compound (I) comprising: distilling a mixture comprising: an aprotic organic solvent, a protic organic solvent, Compound (I) and seed Compound (I), or comprising: distilling a mixture comprising: an aprotic organic solvent and Compound (I), and crystallizing Compound (I) by creating a second mixture comprising: a protic organic solvent, Compound (I) and seed Compound (I). Processes disclosed herein describe more stable, storage compatible preparations of Compound (I). Also disclosed are preparations of Compound (I) which have fewer (trace) impurities.
Owner:CORTEVA AGRISCIENCE LLC

A sterile cefepime hydrochloride and a direct preparation method thereof

The application belongs to the technical field of biological medicine, and particularly relates to a sterile cefepime hydrochloride and a direct preparation method thereof. The method comprises the following steps: firstly, 7-MPCA solution and AE active ester solution are simultaneously subjected to condensation reaction through a solid alkali catalyst column; then, the condensation liquid is subjected to extraction and phase separation, twice pH adjustment and crystallization, active carbon decolorization and sodium sulfite reduction to obtain cefepime hydrochloride to be crystallized; then, a part of the cefepime hydrochloride to be crystallized is prepared into a seed crystal mixed solution, the remaining cefepime hydrochloride to be crystallized and a crystallization solvent are added into the seed crystal mixed solution at a specific speed to obtain sterile cefepime hydrochloride. The method realizes continuous production of sterile cefepime hydrochloride, greatly shortens the preparation period of sterile cefepime hydrochloride, reduces side reactions and product degradation, and the obtained cefepime hydrochloride product is high in quality and yield and stable, and is beneficial to industrial production.
Owner:NORTH CHINA PHARMA HEBEI HUAMIN PHARMA

Cefotaxime acid and a continuous process for its preparation

The application belongs to the technical field of biological medicine, and specifically provides a cefotaxime acid and a continuous preparation method thereof. The method comprises the following steps: firstly, mixing 7-ACA suspension liquid with triethylamine solution; then, condensing the mixture with AE-active ester solution; then, extracting and separating the condensate liquid twice through an extraction separation device and methylene chloride back extraction to obtain an aqueous phase; reacting the aqueous phase with hydrochloric acid to obtain cefotaxime acid crystallization liquid; finally, taking part of the cefotaxime acid crystallization liquid to prepare seed crystal mixture liquid, adding the remaining cefotaxime acid crystallization liquid and crystallization solvent into the seed crystal mixture liquid at a specific speed to obtain cefotaxime acid. The method realizes continuous preparation of cefotaxime acid, significantly shortens the preparation period, improves the production efficiency, reduces the side reaction and product degradation, lays a foundation for preparing high-quality cefotaxime acid, and is beneficial to industrial production.
Owner:NORTH CHINA PHARMA HEBEI HUAMIN PHARMA

Method, equipment and system for extracting and purifying phosphoric acid in anodizing chemical polishing waste liquid

The invention discloses an extraction and purification method, purification equipment and system for anodic oxidation chemical polishing waste liquid phosphoric acid, relates to the technical field of waste liquid recovery and phosphoric acid purification, and solves the technical problems that the existing anodic oxidation chemical polishing waste liquid phosphoric acid extraction effect is poor, and the purity needs to be improved. S2, an impurity removal agent is added into the chemical polishing waste acid solution obtained after preliminary filtration and impurity removal in the step S1, solid-liquid separation is conducted after mixing, and clear liquid and sediment are obtained; s3, carrying out negative-pressure low-temperature evaporation on the clear liquid obtained in S2 to obtain concentrated liquid; s4, phosphoric acid seed crystals are added into the concentrated solution obtained in S3 for crystal growth purification, and purified phosphoric acid is obtained.The purification system comprises a filtering device, a precipitation tank, a storage tank, Mcllaval low-temperature evaporation equipment and purification equipment which are arranged in sequence, and the technical effects that the purity of obtained phosphoric acid is high, and the electronic grade E1 is achieved are achieved.
Owner:MAX INTELLIGENT DYNAMIC CO LTD

Production method and system of melamine

The invention relates to the technical field of melamine, and discloses a production method and system of melamine. The generation method comprises the following steps: taking urea as a raw material to react to obtain melamine, and collecting mixed gas containing the melamine; the method comprises the following steps: sequentially carrying out cooling filtration, fluidization crystallization and gas-solid separation on the mixed gas containing melamine, and collecting solids to obtain a melamine product; the fluidized crystallization comprises the following steps: the cooled and filtered mixed gas and medium particles enter a fluidized bed crystallizer for fluidized crystallization to obtain mixed gas containing melamine crystals, and the mixed gas containing the melamine crystals is discharged from the top of the fluidized bed crystallizer.
Owner:SICHUAN GOLDEN ELEPHANT SINCERITY CHEM CO LTD +1

Lithium compound manufacturing method and lithium compound manufacturing device

Provided is a method for producing a lithium compound, by which a high purity lithium compound can be efficiently produced from low quality lithium carbonate containing impurities such as salt water, the method comprising: mixing lithium carbonate, an acid such as an organic acid and water in a reaction tank 1 to produce an aqueous organic acid lithium compound solution containing an organic acid lithium compound; mixing the organic acid lithium compound and a metal hydroxide in a reaction tank 2 to produce an aqueous lithium hydroxide solution; returning an organic acid, which is regenerated by means of an electrochemical device from an organic acid metal compound by-produced when the aqueous lithium hydroxide solution is produced, to the reaction tank 1, and using this as the organic acid. Also provided is an apparatus for producing a lithium compound, the apparatus having the reaction tank 1, the reaction tank 2, the electrochemical device and a return pipe, each of which have a specific function.
Owner:IDEMITSU KOSAN CO LTD