222results about "Preparation by halogen replacement" patented technology

To provide a fluorinating agent that can be produced using a simple method, and a fluorination method that uses a fluorinating agent that can be produced using a simple method.SOLUTION: The present disclosure provides a fluorinating agent that comprises a fluorine-containing compound and fluoride ions.SELECTED DRAWING: None

The invention provides an HCFC-22 production method with net zero emission of by-product HFC-23, a production process system integrates a conversion and utilization process system of the by-product HFC-23 in the HCFC-22 production process, the HCFC-22 production process is coupled with a conversion process of HFC-23 and CHCl3, the by-product HFC-23 generated in the HCFC-22 production process is directly converted into HCFC-22 and HCFC-21 in the system, and the HCFC-22 and CHCl3 are converted into HCFC-22 and CHCl3. Through further separation and purification and raw material index control, the HFC-23 conversion catalyst keeps good activity, selectivity and stability, HFC-23 generated in the HCFC-22 production process can be effectively converted, and zero emission of HFC-23 in a system is achieved. The method is simple in process, low in investment cost, low-carbon, environment-friendly, efficient in emission reduction and capable of realizing net zero emission of the byproduct HFC-23 of the HCFC-22 production system.

The invention belongs to the field of fine chemical engineering, and discloses a method for synthesizing 2, 3-dimethyl-2-isopropyl butyronitrile, which comprises the following steps of: adding an organic amine solvent into a high-pressure reaction kettle, adding sodium amide, sodium iodide and a phase transfer catalyst into the reaction kettle under the protection of nitrogen and in a stirring state, stirring for a certain period of time, and reacting for 2-3 hours to obtain 2, 3-dimethyl-2-isopropyl butyronitrile. Dropwise adding a mixed solution of propionitrile and 2-bromopropane into the reactor, controlling the dropwise adding speed and the reaction temperature, continuously reacting for a period of time after the dropwise adding is finished to obtain a reactant solution, cooling the reactant solution, adding water, standing for layering, collecting an organic phase, distilling the organic phase at normal pressure to recover a solvent, and rectifying at reduced pressure to obtain 2, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3-pentanediol. According to the method, the sodium iodide, the phase transfer catalyst and the organic amine have a synergistic effect, so that the reaction time is shortened, and the yield of the product is improved.

The invention belongs to the technical field of octafluorocyclopentene gas preparation, and particularly relates to a catalytic synthesis method of octafluorocyclopentene. The method specifically comprises the following step: under the action of a fluorine-chlorine catalyst, carrying out gas-phase catalytic fluorination reaction on 1-chloroheptafluorocyclopentene and anhydrous hydrogen fluoride at 80-120 DEG C to obtain octafluorocyclopentene. The preparation method of the fluorine-chlorine catalyst comprises the following steps: dissolving metal chloride in water, adding a precipitant, and fully stirring for reaction to obtain slurry; filtering the slurry to remove filtrate to obtain a solid, and washing the solid with deionized water until the solid is neutral; adding aluminum nitrate into the washed solid, fully stirring and drying to obtain a precursor of the catalyst; and performing compression molding on the precursor of the catalyst, roasting, and activating to obtain the fluorine-chlorine catalyst. The method is mild in reaction condition and high in catalytic efficiency.

The present invention relates to the technical field of chemistry, particularly to a 2, 3, 3, 3-tetrafluoropropene preparation method, which comprises: mixing a water-soluble metal salt containing a first metal auxiliary agent and chromium chloride hexahydrate to prepare a first solution, mixing the first solution with first ammonia water, and carrying out first calcination treatment on the obtained first precipitate to obtain a first chromium salt; mixing first chromium salt with graphite and silicon dioxide to obtain a first catalyst precursor, and performing fluorination activation treatment on the first catalyst precursor to obtain a first catalyst; the method comprises the following steps: under the action of a first catalyst, reacting 2-chloro-3, 3, 3-trifluoropropene with hydrogen fluoride to obtain 2, 3, 3, 3-tetrafluoropropene. According to the method, the process route is shortened, the use of highly toxic substances is avoided, the cost is reduced, the pollution to the environment is reduced, and meanwhile, the conversion rate of HCFO-1233xf and the selectivity of HFO-1234yf are improved.

The invention relates to the technical field of preparation of hydrofluoroolefin, in particular to a method for preparing 2, 3, 3, 3-tetrafluoropropene, which comprises the following steps: carrying out fluorination reaction on 3, 3, 3-trifluoro-2-chloropropene and excessive hydrogen fluoride under the action of a catalyst to generate a first mixture flow containing 1, 1, 1, 2, 2-pentafluoropropane (245cb), and separating the first mixture flow from the first mixture flow to obtain the 2, 3, 3, 3, 3-tetrafluoropropene. Then directly introducing the first mixture flow into a dehydrofluorination reactor for gas phase dehydrofluorination reaction to generate a second mixture flow containing 2, 3, 3, 3-tetrafluoropropene, hydrogen fluoride and unreacted raw materials, finally condensing the second mixture to remove hydrogen chloride, condensing and recycling hydrogen fluoride to obtain a third mixture flow, and rectifying the third mixture flow to obtain 2, 3, 3, 3-tetrafluoropropene. And 3, 3, 3, 3-tetrafluoropropene. According to the invention, unavoidable process wastes in the prior art are converted into recyclable reaction raw materials, the environmental protection and economic pressure of by-product treatment in the prior art is eliminated, meanwhile, the purpose of continuous flow reaction is effectively realized, and the process control difficulty and the process cost are reduced.

Systems and methods for the preparation of (Z)-1, 1, 1, 4, 4, 4-hexafluoro-2-butene are provided. Compositions prepared according to one or more of the systems and methods described herein and methods of using these compositions are also provided.

The invention relates to an improved process for the manufacture of a fluorinated organic compound, wherein the process comprises a fluorination reaction of an organic precursor compound having at least one chlorine substituent and / or at least one double bond, and said organic precursor compound is reacted in liquid phase in HF (hydrogen fluoride) serving as solvent and fluorinating agent in the presence of a fluorinating catalyst, and wherein the fluorination reaction is performed in liquid phase in a SiC block chemical reactor, and wherein the reaction mixture is withdrawn from SiC block chemical reactor, and wherein the process comprises optionally isolating and / or purifying the targeted fluorinated organic compound.

The application discloses a continuous production process and equipment for a trifluoromethylbenzene tower, and belongs to the field of organic fluorine chemistry. The production process comprises the following steps: S1: continuously feeding trichloromethylbenzene and hydrogen fluoride into a tower reactor connected with a heat exchanger circulating cooling system in a reverse direction, so that a three-stage continuous fluorination reaction occurs in the tower reactor to obtain crude trifluoromethylbenzene, and unreacted hydrogen fluoride is separated into liquid at the top of the tower and then flows back into the tower reactor; S2: the crude trifluoromethylbenzene obtained in the reaction is subjected to nitrogen bubbling in a bubble tower, and then is continuously distilled in a rectifying tower to obtain finished trifluoromethylbenzene; and S3: byproduct hydrogen chloride generated in the fluorination reaction is introduced into a hydrochloric acid tank to obtain hydrochloric acid, and the content of hydrofluoric acid in the hydrochloric acid is less than 1000 ppm. The method can greatly improve the utilization rate of raw material hydrogen fluoride, improve the purity of byproduct hydrochloric acid, reduce the generation amount of waste acid, avoid the sharp change of pressure in the reaction process, and realize large-scale, continuous, stable and safe production of trifluoromethylbenzene.

The present invention provides a method for the co-production of 1,1-difluoroethane and vinyl chloride, including: (a) vaporizing dichloroethane and hydrogen fluoride, and delivering the vaporized dichloroethane and hydrogen fluoride into a reactor for a catalytic reaction under the action of a catalyst to obtain a reaction product; (b) delivering the reaction product into a first rectifying tower for separation to obtain an overhead product from the first rectifying tower and a bottom product from the first rectifying tower; (c) delivering the overhead product from the first rectifying tower into a second rectifying tower for separation to obtain hydrogen chloride and a bottom product from the second rectifying tower; (d) delivering the bottom product from the second rectifying tower into a purifying tower for purification to obtain an overhead product from the purifying tower; (e) simultaneously delivering the overhead product from the purifying tower and a saturated organic solvent into a third rectifying tower for separation to obtain a 1,1-difluoroethane product and a bottom product from the third rectifying tower; and (f) delivering the bottom product from the third rectifying tower into a fourth rectifying tower for separation to obtain a vinyl chloride product and a bottom stream from the fourth rectifying tower. The present invention has the advantages of simple process, high conversion rate, and good product quality.

The invention provides a preparation method of dichlorohexafluorocyclopentene. Perhalogenated cyclopentene or / and perhalogenated cyclopentadiene is used as a raw material and reacts with HF and Cl2 in a tubular reactor filled with a catalyst to generate dichlorohexafluorocyclopentene, the catalyst needs to be used after being activated for 2-12 h in a mixed gas of HF and F2 at the temperature of 200-600 DEG C, and the catalyst is one or more of molybdenum fluoride, nickel fluoride, cobalt fluoride or molybdenum fluoride; the reaction conditions are as follows: the molar ratio of HF to Cl2 to octachlorocyclopentene or hexachlorocyclopentadiene is (4-10): (1-5): 1, the reaction temperature is 200-500 DEG C, the reaction pressure is 0-2.0 MPa, and the catalyst contact time is 5-90 seconds. According to the method, the reaction process is simple, the needed target object is prepared through one-step gas-phase catalytic fluorination, the method is suitable for large-scale production of dichlorohexafluorocyclopentene, the requirement for equipment is low, and the catalyst activity and stability are high.

The invention discloses a synthesis method of octafluorocyclopentene, which comprises the following steps: 1, carrying out gas phase catalytic fluorination reaction on octachlorocyclopentene and fluorine gas to obtain an intermediate 1, 2-dichlorohexafluorocyclopentene; and 2, by taking the obtained intermediate 1, 2-dichlorohexafluorocyclopentene and anhydrous potassium fluoride as raw materials and dimethyl sulfoxide as a solvent, carrying out high-temperature substitution reaction on the raw materials and potassium fluoride to generate octafluorocyclopentene. The first-step reaction and the second-step reaction are carried out through a circulating system, so that materials can be completely reacted and fully utilized, the pollution is greatly reduced, and the industrial continuous production of octafluorocyclopentene can be realized.

The invention relates to bio-based vinylidene difluoride. The invention also relates to processes for preparing bio-based vinylidene difluoride from various renewable raw materials. The invention further relates to vinylidene difluoride homopolymers obtained by polymerization of said monomer, as well as copolymers obtained by copolymerization of said monomer with one or more compatible co-monomers. Finally, the invention relates to the use of said homopolymers or copolymers in applications such as chemical engineering or electronics, particularly consumer electronic devices.

The present invention discloses a method for preparing perfluorooctyl bromide by catalytic bromination of perfluorooctyl iodide. First, fluorosilicic acid reacts with aluminum hydroxide, and after filtering to remove silicon dioxide, a mixed solution of fluoroaluminate and fluorosilicic acid is obtained. Then, a soluble metal salt additive and graphite powder are added thereto. After coprecipitation, granulation, and sintering, metal oxide-doped aluminum-based catalyst particles are obtained, which are loaded into a fixed-bed reactor. After fluorination with an N2 / HF mixed gas, perfluorooctyl iodide and bromine are vaporized and mixed and then enter the fixed-bed reactor, and perfluorooctyl bromide is prepared by reaction. In the present invention, the reaction raw materials are easily available; the reaction conditions are mild, and materials and equipment matching the process can be found in the existing equipment and material system to support the long-term stable operation of production; through the efficient catalysis of the catalyst and the continuous progress of the reaction gas phase, the reaction efficiency is improved and the consumption of bromine is reduced, so that the whole process has good atom economy and has good application prospects.

A method for producing a hydrofluorocarbon (HFC) is provided, the method being excellent in terms of the conversion of a chlorofluorocarbon and reduced in the formation of by-products.　This method for producing an HFC comprises reacting a chlorofluorocarbon (1A) with hydrogen in the presence of a catalyst to produce a hydrofluorocarbon (2A) in which one or two of the chlorine atoms of the chlorofluorocarbon (1A) have each been replaced with a hydrogen atom, the reaction being conducted using a reactive mixture comprising the chlorofluorocarbon (1A), hydrogen, and hydrogen chloride and having a hydrogen chloride concentration of 100-10,000 mass ppm of the chlorofluorocarbon (1A).

The invention discloses a preparation method of p-chlorobenzotrifluoride, and belongs to the technical field of fluorine-containing carbocyclic compounds, the preparation method comprises the following steps: preparation of carbazolyl copolymer microspheres, chlorination reaction, fluorination reaction and rectification; according to the invention, a four-tower series continuous chlorination reaction system is adopted, each reaction tower independently controls the ultraviolet light power and temperature, and the chlorination reaction is intensified in a segmented manner, so that high-efficiency reaction in the front, middle and later stages is realized; the first tower is mainly used for monochlorination, the second tower is used for deepening dichlorination, the third tower and the fourth tower are used for realizing efficient conversion of polychlorinated products, the reaction time is shortened, the generation of side reaction impurities is reduced, the energy consumption is reduced, the yield and purity of target products are improved, the temperature rise in the reaction process is easier to control, and the safety of the reaction process is further improved. The purity of the parachlorobenzotrifluoride prepared by the method disclosed by the invention is 99.61 to 99.72 percent, and the two-step yield of the parachlorobenzotrifluoride is 96.48 to 96.65 percent.

The present application discloses a full-process continuous process for synthesizing 1,1,1,3,3-pentafluoropropane, including a telomerization reaction: vinyl chloride, carbon tetrachloride, catalyst 1 and a cocatalyst are added to a pre-reactor mixer for premixing to obtain mixture 1, mixture 1 is pumped into a reactor system for telomerization reaction to obtain the material of the telomerization reaction, the material of the telomerization reaction is continuously pumped out and separated to obtain R240fa, and the separated vinyl chloride, carbon tetrachloride, catalyst 1, cocatalyst and unseparated R240fa are returned to the pre-reactor mixer for continuous reaction; a fluorination reaction: the R240fa, chlorine gas and anhydrous hydrogen fluoride obtained from the telomerization reaction are continuously introduced into a fluorination reaction kettle containing activated catalyst 2 for fluorination reaction to obtain a fluorination reaction product, the fluorination reaction product is separated to obtain 1,1,1,3,3-pentafluoropropane, and the remaining product after separating 1,1,1,3,3-pentafluoropropane is returned to the fluorination reaction kettle for continuous reaction.

The invention provides a fluorination catalyst composition, a preparation method and application thereof, and a method for catalyzing 1, 1, 1, 3, 3-pentachloropropane to generate E-1-chloro-3, 3, 3-trifluoropropene, and belongs to the field of materials. The fluorination catalyst composition comprises a main catalyst and a third metal element loaded on the main catalyst, wherein the main catalyst is biomass charcoal simultaneously modified by a first metal element and a second metal element; wherein the first metal element comprises at least one of rare earth metal elements; the second metal element comprises at least one of Zr, Nb, Mo, V, Fe, Mn, Ti, Hf, Ga, In and Sn; the third metal element comprises at least one of Mg, Ca, Ba and Sr. The fluorination catalyst composition provided by the invention can efficiently catalyze 1, 1, 1, 3, 3-pentachloropropane to generate a gas phase fluorination reaction to generate E-1-chloro-3, 3, 3-trifluoropropene, has the advantages of high conversion rate, strong selectivity, long service life and the like, and is suitable for wide application.

Minimum-boiling, heterogeneous azeotropic and azeotrope-like compositions including 1,1,2,2,3-pentachloropropane (HCC-240aa) and hydrogen fluoride (HF), as well as methods for using these azeotropic or azeotrope-like compositions in the production of trifluorochloropropenes.

A method for the production of (Z)-1,1,1,4,4,4-hexafluoro-2-butene (Z-1336mzz) is described, utilizing readily available halogenated starting materials, such as 1,1,1-trichloro-2,2,2-trifluoroethane (CFC-113a) and carbon tetrachloride.

A method of synthesizing 3,3,3-trifluoropropene including contacting 1,1,1,3-tetrachloropropane, in the vapor phase, at a temperature sufficient to effect dehydrochlorination to form 1,1,3-trichloro-1-propene. The 1,1,3-trichloro-1-propene is isolated and subsequently contacted, in the vapor phase, with hydrogen fluoride in the presence of a fluorination catalyst at a temperature sufficient to effect formation of 3,3,3-trifluoropropene.

The invention discloses a preparation method of 2-bromo-1, 1, 1, 3, 3, 3-hexafluoropropane, and belongs to the technical field of synthesis of fluorine-containing intermediates. According to the preparation method, perfluoro-2-methyl-2-pentene and hypobromite are used as raw materials, 2-bromo-1, 1, 1, 3, 3, 3-hexafluoropropane is prepared under the action of an aprotic polar solvent under the low-temperature condition, the preparation method is low in cost and easy to obtain, the steps are simple and convenient, the reaction conditions are mild and rapid, and the method is suitable for industrial production. And a stable and reliable intermediate source is provided for downstream fields of fluorine-containing medicines, electronic chemicals and the like.

Provided are a fluorinating agent that can be produced using a simple method, and a fluorination method that uses a fluorinating agent that can be produced using a simple method. The present disclosure provides a fluorinating agent that comprises a fluorine-containing compound and fluoride ions.

A process is provided which includes contacting a haloalkane reactant with a fluorination agent in the liquid phase, in the presence of a catalyst, under conditions which are free of or substantially free of a superacid, to produce a product stream including a haloalkane product, preferably a hydro(chloro)fluorocarbon.

The utility model discloses a monochlorodifluoromethane production and separation device, which comprises a fluorination reaction kettle (1) and a fluorinated product concentration tower (2) connected with the fluorination reaction kettle (1), the fluorinated product concentration tower (2) is connected to a monochlorodifluoromethane product tank, the fluorinated product concentration tower (2) is also connected to a disproportionation reactor (3), and the disproportionation reactor (3) is connected with the fluorination reaction kettle (1). The disproportionation reactor (3) is connected to a disproportionation product concentration tower (4) through a pre-concentration tower (5), a pre-cooler (7) is arranged on the periphery of the pre-concentration tower (5), a tower top condenser (6) is arranged on the periphery of the top of the disproportionation product concentration tower (4), and the bottom of the pre-concentration tower (5) is connected to the fluorination reaction kettle (1) through a second return pipe (9). Reaction products are effectively separated, the utilization rate of all materials is high, continuous production and operation can be achieved, energy consumption is reduced, and operation is convenient.

The present invention provides a method for the hydrodehalogenation of halogenated alkanes promoted by visible light, and belongs to the technical field of organic synthesis. The present invention carries out the hydrodehalogenation of halogenated alkanes under the condition of visible light illumination, and initiates free radicals under the promotion of visible light to realize the cleavage of the carbon-halogen bond of the halogenated alkanes to generate alkyl free radicals, and simultaneously utilizes mercaptan to provide a hydrogen source to generate a reduction hydrogenation product, and the addition of an organic amine is conducive to the capture of the halogen free radicals generated by the reaction, thereby improving the reaction rate and having a high yield. The method of the present invention is simple to operate, and the reaction conditions are mild, and the reaction can occur at room temperature. The hydrogen source is mercaptan, and has good tolerance to reducible functional groups such as carbon-carbon double bonds, ester groups, and cyano groups, and therefore has good functional group tolerance and a wide range of substrates.

Provided is a method for producing a fluoroethane compound with which it is possible to efficiently produce a fluoroethane compound that is a target product. Comprising a step (A) in which the chlorofluoroethane compound according to the present invention is subjected to a reduction reaction in the presence of a catalyst in which at least one metal selected from the group consisting of Ni, Pd, Pt, Ru and Rh is supported on activated carbon to produce a product containing a fluoroethane compound. With this production method, a fluoroethane compound, which is a target product, can be efficiently produced.

There is provided a method for producing chlorofluorobutane (CFB) by forming chlorinated butadiene by dimerizing trichloroethylene (TCE) and fluorinating hydrogen atoms of the chlorinated butadiene. Trichloroethylene (TCE) is dimerized by using a dimer represented by the following formula (1) as a solvent and in the presence of a free radical generating agent at a temperature of 100° C. or higher. Hexachlorobutadiene (C4Cl6) is produced from the above dimer by chlorination and dehydrochlorination reaction, and further, the chlorofluorobutane (CFB) is produced by fluorinating the hexachlorobutadiene.

The invention relates to the technical field of organic synthesis, in particular to a synthesis method of 1-chloro-3, 3, 3-trifluoropropene, which comprises the following steps: S1, firstly, metering an organic raw material HCC-240fa, feeding the metered organic raw material HCC-240fa into a preheater, and mixing the metered organic raw material HCC-240fa with anhydrous hydrofluoric acid (HF); 2, HFC-245fa formed by mixing HCC-240fa and anhydrous hydrofluoric acid is heated through a preheater, then a fluorination catalyst is added into the HFC-245fa, stirring is conducted again, and then 1-chloro-3, 3, 3-trifluoropropene is synthesized through gas phase fluorination; and S3, carrying out water washing, alkali washing and drying on the obtained 1-chloro-3, 3, 3-trifluoropropene reaction product, and carrying out online gas chromatographic analysis to determine the purity and yield of the product. According to the invention, 1-chloro-3, 3, 3-trifluoropropene is subjected to water washing, alkali washing and drying, then on-line gas chromatographic analysis is carried out to remove inorganic salts and other impurities in the 1-chloro-3, 3, 3-trifluoropropene, the washed product is subjected to alkali washing to further neutralize residual acidic substances, and finally, drying treatment is carried out to ensure the purity and stability of the product, so that the product quality is improved. According to the method, the 1-chloro-3, 3, 3-trifluoropropene can be effectively purified and refined, and the quality and the purity of the 1-chloro-3, 3, 3-trifluoropropene are improved.