150 results about "Dehydrohalogenation" patented technology

A process for the production of fluorinated olefins, preferably fluorinated propenes, by contacting a feed stream containing a fluorinated olefin and hydrogen with a first amount of catalyst to produce the hydrofluorocarbon, wherein a first exit stream contains unreacted fluorinated olefin and hydrogen; contacting the first exit stream with a second amount of catalyst to produce a hydrofluorocarbon, wherein the second amount of catalyst is preferably greater than the first amount of catalyst; and contacting the hydrofluorocarbon with a catalyst for dehydrohalogenation to produce a product stream of fluorinated olefin.

A process for making a fluorinated olefin having the step of dehydrochlorinating a hydrochlorofluorocarbon having at least one hydrogen atom and at least one chlorine atom on adjacent carbon atoms, preferably carried out in the presence of a catalyst selected from the group consisting of (i) one or more metal halides, (ii) one or more halogenated metal oxides, (iii) one or more zero-valent metals/metal alloys, (iv) a combination of two or more of the foregoing.

A photochemical reaction apparatus including a reactor and a light source situated so that light from the light source is directed through a portion of the reactor wall is disclosed. The apparatus is characterized by the portion of the reaction wall comprising a functionalized copolymer of a terminally functionalized perfluoro(alkyl vinyl ether). Also described is a photochemical reaction process using said reactor. The functional group of the copolymer of the apparatus and the process is selected from —SO₂F, —SO₂CI, —SO₃H, —CO₂R (where R is H or C1-C3 alkyl), —PO₃H₂, and salts thereof. A process for increasing the flourine content of at least one compound selected from hydrocarbons and halohydrocarbons, comprising: (a) photochlorinating said at least one compound, and (b) reacting the halogenated hydrocarbon in (a) with HF. A process for producing an olefinic compound, comprising: (a) photochlorinating at least one compound selected from hydrocarbons and halohydrocarbons containing at least two carbon atoms and at least two hydrogen atoms to produce a halogenated hydrocarbon containing a hydrogen substituent and a chlorine substituent on adjacent carbon atoms; and (b) subjecting the halogenated hydrocarbon produced in (a) to dehydrohalogenation.

Disclosed is a process for preparing cis-1,1,1,4,4,4-hexafluoropropene comprising the steps of (a) reacting CCl₄ with a compound having the formula CF₃CX═CXH, where each X is independently halogen or hydrogen, to form a compound having the formula CF₃CXClCXHCCl₃; (b) fluorinating the compound formed in step (a) to form a compound having the formula CF₃CXHCXHCF₃; (c) converting the compound formed in step (b) by a reaction selected from the group consisting of dehydrohalogenation, dehalogenation and both reactions, to form a compound having the formula CF₃C≡CCF₃; and (d) catalytically reducing the compound formed in step (c) with hydrogen to form the compound having the formula:

The invention discloses a magnesium fluoride-based catalyst which is stable at the temperature of over 400 DEG C and large in specific surface area and application of the magnesium fluoride-based catalyst. The invention aims at solving the problems such as low thermal stability and small specific surface area existing in the preparation of the magnesium fluoride-based catalyst in the prior art. The method for preparing the magnesium fluoride-based catalyst disclosed by the invention comprises the following steps: (1) preparing a turbid liquid solution containing a magnesium metal insoluble salt and a surfactant, refluxing at the temperature of 100 DEG C, roasting under the condition of 400-550 DEG C for 4 hours, thereby obtaining magnesium oxide with the large specific surface area; (2) dropwise adding an aqueous solution of hydrofluoric acid or ammonium fluoride into the magnesium oxide base body obtained in the step (1) for fluorinating, roasting at the temperature of 400-500 DEG C for 4 hours, thereby preparing magnesium fluoride; and (3) dropwise adding the aqueous solution doped with components into the magnesium oxide base body obtained in the step (2), and finally roasting at the temperature of 400-500 DEG C so as to prepare the catalyst. According to the catalyst disclosed by the invention, high-efficiency dehydrohalogenation reaction can be realized by virtue of halofluoroalkane.

The invention discloses a catalyst for greenly synthesizing halogenated arylamine by means of catalytic hydrogenation of a halogenated aromatic nitro compound. The catalyst comprises a carrier and anactive component and is characterized in that TiO2, ZrO2, neutral Al2O3 or active carbon is used as the carrier, and a bi-component metal consisting of Au and Pt, Pd, Ir or Ru is used as the active component, wherein the metal accounts for 0.1-2.0% of the carrier in terms of weight percent and the two metal elements (the Au and the Pt, Pd, Ir or Ru) in the bi-component metal keep a weight ratio of1.0:0.1-0.5. The catalyst is highly active and selective during the preparation of the halogenated arylamine by means of catalyzing the hydrogenation of the halogenated aromatic nitro compound, can achieve 100% of raw material conversion rate and 100% of target product selectivity in conditions of normal temperature, 1MPa and H2 and causes no dehalogenation reaction. In addition, the catalyst hasstable activity, can be repeatedly used for a plurality of times and can conveniently cause the catalyst to be separated from a product after the reaction. The adoption of the process for preparing the halogenated arylamine can lead to low cost and zero pollution, and has relatively great implementing value and social and economic benefits.

The invention provides a photocatalytic halohydrocarbon dehalogenation conversion method which comprises the following steps: adding a photocatalyst quantum dot/rod into a solvent to obtain a solutionA; adding halohydrocarbon and an electronic sacrificial body into the solution A to obtain a solution B; utilizing a light source to irradiate the solution B and catalyzing the solution B to performhalohydrocarbon dehalogenation conversion. According to the photocatalytic halohydrocarbon dehalogenation conversion method disclosed by the invention, a nano quantum dot and a nano quantum rod are applied to dehalogenation conversion reaction of alkyl halide, alkenyl halide and alkyne halide for the first time; the reaction conditions are moderate, visible light is utilized as driving energy, a product is hydrocarbon compound, and the whole process has the advantages of environmental protection, conciseness and high efficiency. In addition, higher hydrocarbon of carbon chain growth can be generated after dehalogenation reaction, so that the method has potential application in preparation of higher hydrocarbon. According to the method disclosed by the invention, halohydrocarbon dehalogenation conversion and deuteration marking processes are jointly performed; hydrocarbon deuteration marking can be finished when a halohydrocarbon dehalogenation process is finished. The invention furtherprovides a method for performing deuteration marking on hydrocarbon.

Oxides CeO2, ZrO2, La2O3 and Pr6O11 or their salts are prepared into mixed ionic nitric acid solution; small amount of surfactant and carbon nanotube are added into precipitant solution to prepare mixed precipitant solution; two kinds of solution are made to react to produce precipitate; and the precipitate is incinerated at 400-700 deg.c to obtain quarternary nanometer-level cerium-based carbon nanotube-containing composite RE oxide. The composite oxide has high specific surface area at both low temperature and high temperature and high heat stability. It may be used in various catalytic reaction process, such as hydrosulfurization, hydrodenitrification, dehydrohalogenation, internal combustion engine waste gas treatment and dehydrocyclization of hydrocarbon and other organic matters, and is especially suitable for use in purifying automobile tail gas.

The invention discloses a catalyst used in preparation of fluorine-containing olefin through dehydrohalogenation of halohydrofluoroalkane. The catalyst is represented as nwt. %Y/X, wherein Y represents a catalyst promoter and is one or more selected from alkali metal ions Na<+>, K<+> and Cs<+>, rare earth metal ions La<3+>, Ce<4+>, Y<3+> or high-valence metal ions Al<3+>, Fe<3+>, Ti<4+> and Zr<4+>; X represents a main active ingredient and is one or a mixture of more of alkali metal magnesium, calcium and/or barium oxide; n is the using amount of the catalyst promoter and accounts for 30 percent of the main active ingredient at most; and the catalyst is mainly used for preparation of the fluorine-containing olefin through gas-phase dehydrohalogenation of the halohydrofluoroalkane.

Halofluorinated alkylene monomers are made by a method comprising the steps of: (a) subjecting a first polymer which is the reaction product of a fluorinated vinyl monomer and a vinyl comonomer to dehydrohalogenation to form a second polymer; (b) treating the second polymer with an oxidizing agent to form an oxidation product consisting of a alpha , omega -dicarboxylic acid or an ester derivative thereof; and (c) treating said oxidation product with a reducing agent to form a reduction product consisting of a a alpha , omega -diol. Preferably, the first polymer has a structure of -[CH2CYZ(CF2CFX)n]m- wherein X and Y=F, Cl or Br; X and Y may be the same or different; Z=H, F, Cl, Br, alkyl or perfluoroalkyl containing from about 1 to about 10 carbon atoms; n=an integer larger than about 1; and m is an integer between about 2 and about 105. The alpha , omega -dicarboxylic acids and alpha , omega -diols produced herein can be directly used as polycondensation monomers. Alternatively, the alpha , omega -dicarboxylic acids and alpha , omega -diols can be further derivitized to tri-, tetra- or other multifunctional alcohols which may be directly used as condensation monomers or they may be converted to acrylates which may be photocured in the presence of a radical photoinitiator into transparent polymers which are useful as optical waveguiding materials.

A process for the manufacture of halogenated olefins in semi-batch mode by dehydrohalogenation of halogenated alkanes in the presence of an aqueous base such as KOH which simultaneously neutralizes the resulting hydrogen halide. During the process, aqueous base is continuously added to the haloalkane which results in better yields, lower by-product formation and safer/more controllable operation.

A process for preparing perfluorovinylethers having general formula: R f O-CF=CF 2 (IA) wherein R f is a C 1 -C 3 alkyl perfluorinated substituent; comprising the following steps: 1a) fluorination with fluorine of olefins of formula: CY''Y=CY'Cl (II) wherein Y, Y' and Y'', equal to or different from each other, are H, Cl, Br, with the proviso that Y, Y' and Y'' are not contemporaneously hydrogen; and obtainment of fluorohalogencarbons of formula: FCY''Y-CY'ClF (III) wherein Y, Y' and Y'' are as above; 2a) dehalogenation or dehydrohalogenation of the fluorohalogencarbons (III) and obtainment of fluorohalogen olefins of formula: FCY I =CY II F (IV) wherein Y I and Y II , equal to or different from each other, have the meaning of H, Cl, Br with the proviso that Y I and Y II are not both H; 3a) reaction between a hypofluorite of formula R f OF and a fluorohalogenolefin (IV), obtaining the fluorohalogenethers of formula: RfO-CFY I -CF 2 Y II (I) wherein Y I , Y II , equal to or different from each other, are Cl, Br, H with the proviso that Y I and Y II cannot be contemporaneously equal to H; 4a) dehalogenation or dehydrohalogenation of the compounds (I) and obtainment of the perfluorovinylethers (IA).

A process is disclosed for producing an olefinic compound from a least one compound selected from hydrocarbons and halohydrocarbons containing at least two carbon atoms and at least two hydrogen atoms. The process involves (a) directing light from a light source through the wall of a reactor to interact with reactants comprising chlorine and said at least one compound in said reactor, thereby producing a saturated halogenated hydrocarbon having increased chlorine content by photochlorination, and (b) dehydrohalogenating said saturated halogenated hydrocarbon produced by the photochlorination in (a); and is characterized by the light directed through the reactor wall being directed through a poly(perhaloolefin) polymer.

The invention relates to a method of preparing halogen aromatic amine by catalyzing aryl halide nitrocompound through selective hydrogenation. The method comprises the following steps: in scCO2, a non-noble metal Ni catalyst is adopted to catalyze the aryl halide nitrocompound and prepare the halogen aromatic amine through selective hydrogenation under the low temperature ranging from 31 to 100 DEG C; in the scCO2, the hydrogenation speed of -NO2 group in the aryl halide nitrocompound is higher than the speed in ethanol obviously, and the dehalogenation reaction is markedly inhibited, so that the selectivity of the halogen aromatic amine is more than 99 percent is realized. The cost of the Ni catalyst is lower than a noble metal catalyst; the Ni catalyst has ferromagnetism at the same time, thereby providing the possibility to the reactor operation and the catalyst separating by adopting an external magnetic field.

The invention relates to a preparation method of vinylene carbonate, which comprises halogenated ethylene carbonate and dehydrohalogenation agent which are subject to contact reaction. The dehydrohalogenation agent is ammonia with a purity of not less than 99.9 percent. The yield of the vinylene carbonate prepared by adopting the method provided by the invention reaches as high as 85 percent, resultant can be quite easily separated and purified, and the purity of the resultant can reach 99.5 percent (GC) through general distillation and a crystallization method. Raw materials of the dehydrohalogenation agent can be easily obtained at low price; furthermore, excessive ammonia can be recycled, so the production cost is greatly reduced compared with using organic amine as the dehydrohalogenation agent. In addition, molecular weight of the ammonia that is used as the dehydrohalogenation agent is small, thus greatly reducing the weight of side products under the same situation.

The invention relates to a method for synthesizing indoline in formula (I) and a derivative thereof. Titanium dioxide laden copper of Cu/TiO2 with a charge number between 5 and 15 weight percent is taken as a catalyst. The a compound in formula (II) and the catalyst have condensation reaction under the action of a dehydrohalogenation agent to produce the indoline, wherein R1, R2, R3 and R4 represent hydrogen, C1 to C4 represent alkyl, C1 to C4 represent alkoxyl group and nitryl, and C1 to C4 represent hydroxyalkyl; and R5 represents hydrogen, and C1 and C2 represent alkyl. The method avoids the operation at high pressure, avoids the use of raw materials such as organic amine and the catalyst with high price and great toxicity, lowers the cost, improves the operating environment, is easy to reclaim the catalyst and has high yield of the product.

The invention provides a method and a system for processing wastes of halogenated POPs (Persistent Organic Pollutants). The method comprises the steps of adding catalysts into the wastes of the POPs, wherein the catalysts are alkali metal oxides and/or alkaline earth metal oxides; performing dehalogenation for 0.5-5 hours at the temperature of 250-600 DEG C under an atmosphere condition that the content of oxygen in the environment is less than or equal to 1%; and cooling the wastes after dehalogenation under an anoxic atmosphere condition, and cooling the wastes to below 150 DEG C, thus finishing treatment of the wastes. Meanwhile, the invention also provides a method for implementing the method. Through the technical scheme of the method and the system, the wastes of the halogenated POPs can be effectively subjected to dehalogenation, processing efficiency is good, the processing process is easily-controllable, the cost is low, and the method and the system are applicable to treatment of the wastes of the industrial POPs.

The invention relates to a preparation method of halogenation cycloolefin and belongs to the field of chemical synthesis. According to the preparation method, in an amide or alkylamine solvent, with halogenation cycloparaffin as a raw material, a dehalogenation reaction is conducted, and the target product halogenation cycloolefin is obtained. According to the method, the reaction conditions are mild, the yield of the halogenation cycloolefin is high, dangerous reduction agents such as metal or hydrogen do not need to be used, the technology is safe and reliable, solid waste such as metal halide is not generated, and a common distillation means can be used for effective industrial separation.