1229 results about "Azeotrope" patented technology

Disclosed herein are azeotrope or near-azeotrope compositions comprising 2,3,3,3-tetrafluoropropene (HFC-1234yf) and hydrogen fluoride (HF). These compositions are useful in processes to produce and purify HFC-1234yf. Additionally, disclosed herein are processes for the manufacture of HFC-1234yf.

Provided are azeotrope-like compositions comprising pentafluoropropene (HFO-1225) and a fluid selected from the group consisting of 3,3,3-trifluoropropene (“HFO-1243zf”), 1,1-difluoroethane (“HFC-152a”), trans-1,3,3,3-tetrafluoropropene (“HFO-1234ze”), and combinations of two or more thereof. Also provided are uses thereof including as refrigerants, blowing agents, sprayable compositions, flame suppressant, and the like.

An azeotrope-like mixture consisting essentially of chlorotrifluoropropene and at least one component selected from the group consisting of a C1-C3 alcohol, a C5-C6 hydrocarbon, a halogenated hydrocarbon, methylal, methyl acetone, water, nitromethane, and combinations thereof.

Low water-containing biomass-derived pyrolysis oils and processes for preparing them are provided. Water-containing biomass-derived pyrolysis oil is distilled in the presence of an azeotrope-forming liquid to form an azeotrope. The azeotrope is removed at or above the boiling point of the azeotrope and low water biomass-derived pyrolysis oil is obtained.

Provided are azeotropic and azeotrope-like compositions of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and hydrogen fluoride (HF). Such azeotropic and azeotrope-like compositions are useful as intermediates in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf).

Provided are azeotrope-like compositions consisting essentially of 1,1,1,2-tetrafluoropropene and 1,1,1,2-tetrafluoroethane and uses thereof, including use in refrigerant compositions, refrigeration systems, blowing agent compositions, and aerosol propellants.

Disclosed herein are azeotrope compositions comprising 1,2,3,3,3-pentafluoropropene and hydrogen fluoride. The azeotrope compositions are useful in processes to produce and in processes to purify 1,2,3,3,3-pentafluoropropene.

An azeotrope-like mixture consisting essentially of a binary azeotrope-like mixture consisting essentially of trans-1-chloro-3,3,3-trifluoropropene (trans-HFO-1233zd) and a second component selected from the group consisting of 2,3,3,3-tetrafluoropropene (HFO-1234yf) and trans-1,3,3,3-tetrafluoropropene (trans-HFO-1234ze), and combinations of these and various uses thereof.

The present invention discloses a graphene oxide film preparation method, which comprises: 1) carrying out an oxidation treatment on graphite powder to obtain a graphite oxide, and peeling to form graphene oxide; 2) dissolving the graphene oxide in water to form a clarified graphene oxide sol; 3) carrying out washing and surface treatment on a porous carrier; and 4) forming the graphene oxide film on the porous carrier surface. The present invention further discloses the graphene oxide film prepared according to the method, and applications of the graphene oxide film in water-containing azeotrope separation. According to the present invention, the inexpensive graphite material is used to prepare the graphene oxide composite film, and the prepared graphene oxide composite film has characteristics of high water permeation selectivity and high permeation flux and can effectively separate the water-containing azeotrope so as to provide an efficient, environmentally friendly and economical way for the water-containing azeotrope separation.

Provided are azeotropic and azeotrope-like compositions of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb). Such azeotropic and azeotrope-like compositions are useful as intermediates in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf).

Disclosed herein are azeotrope or near-azeotrope compositions comprising 2,3,3,3-tetrafluoropropene (HFC-1234yf) and hydrogen fluoride (HF). These compositions are useful in processes to produce and purify HFC-1234yf. Additionally, disclosed herein are processes for the manufacture of HFC-1234yf.

Disclosed herein is a process to produce an azeotrope composition comprising a hydrofluoroolefin and hydrogen fluoride, said process comprising, dehydrofluorinating a hydrofluorocarbon containing at least one hydrogen and at least one fluorine on adjacent carbons, thereby forming a mixture comprising said hydrofluoroolefin, unreacted hydrofluorocarbon and hydrogen fluoride, and distilling the mixture to produce a distillate composition comprising an azeotrope composition containing said hydrofluoroolefin and hydrogen fluoride and a column bottoms composition comprising said hydrofluorocarbon essentially free of hydrogen fluoride. Also disclosed herein are processes for separation of hydrofluoroolefins from hydrofluorocarbons and from hydrogen fluoride.

The invention relates to azeotropic and azeotrope-like mixtures of 1,1,1-trifluoroethane (HFC-143a) and hydrogen fluoride and a process for separating the azeotrope-like mixtures. The compositions of the invention are useful as an intermediate in the production of HFC-143a. The latter is useful as a nontoxic, zero ozone depleting fluorocarbon useful as a solvent, blowing agent, refrigerant, cleaning agent and aerosol propellant.

An azeotrope-like mixture consisting essentially of chlorotrifluoropropene and at least one component selected from the group consisting of pentane, hexane, methanol, and trans-1,2-dichloroethene.

Provided are ternary azeotropic and azeotrope-like compositions of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf), 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb), and hydrogen fluoride (HF). Such azeotropic and azeotrope-like compositions are useful as intermediates in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf).

The invention provides a method and apparatus for continuous extraction of plant oils from plant tissue using an advantageous azeotrope of ethanol and water and employing the differing solubility of plant oils in ethanol and water to drive formation of a non-toxic oil tincture.

A liquid phase process is disclosed for producing halogenated alkane adducts of the formula CAR1R2CBR3R4 (where A, B, R1, R2, R3, and R4 are as defined in the specification) which involves contacting a corresponding halogenated alkane, AB, with a corresponding olefin, CR1R2═CR3R4 in a dinitrile or cyclic carbonate ester solvent which divides the reaction mixture into two liquid phases and in the presence of a catalyst system containing (i) at least one catalyst selected from monovalent and divalent copper; and optionally (ii) a promoter selected from aromatic or aliphatic heterocyclic compounds which contain at least one carbon-nitrogen double bond in the heterocyclic ring. When hydrochlorofluorocarbons are formed, the chlorine content may be reduced by reacting the hydrochlorofluorocarbons with HF. New compounds disclosed include CF3CF2CCl2CH2CCl3, CF3CCl2CH2CH2Cl and CF3CCl2CH2CHClF. These compounds are useful as intermediates for producing hydrofluorocarbons. Azeotropes of CClF2CH2CF3 with HF and azeotropes of CF3CH2CHF2 with HF are also disclosed; as are process for producing such azeotropes. A process for purification of certain hydrofluorocarbons and / or chloro-precursors thereof from mixtures of such compounds with HF is also disclosed.

Disclosed is a process for the purification of a mixed diol stream. The mixed diol stream comprising two-, three-, and four-carbon diols is separated into component diols by extraction with a hydrophobic solvent mixture. The diols recovered in the extractant may be removed from the extractant stream by back extraction with water or by distillation with an azeotrope-forming agent present, preferably an azeotroping agent already present in the extractant mixture.

There is provided an azeotrope or azeotrope-like composition containing (A) 1,1,2,2-tetrafluoro-1-methoxyethane and (B) a compound formed of at least one selected from the group consisting of (Z)-1-chloro-3,3,3-trifluoropropene, 2-bromo-3,3,3-trifluoropropene, and (E)-2-bromo-1,3,3,3-tetrafluoropropene.

The invention relates to a method for preparing sec-butyl acetate, which includes steps as follows: (1) with the existence of a catalyst and under the condition of addition reaction, C4 olefin contacts and reacts with acetic acid for a plurality of times; (2) the reaction products obtained in Step (1) are rectified and separated, C4 light components are obtained from the top of a tower and tower bottoms are obtained from the bottom of the tower; (3) the tower bottoms obtained in Step (2) and water are boiled and rectified, sec-butyl acetate and C8 olefin are obtained from the top of the tower in the form of azeotrope and acetic acid is obtained from the bottom of the tower; (4) the azeotrope obtained in Step (3) is condensed, oil and water separation is carried out and aqueous phase products and oil phase products containing C8 olefin and sec-butyl acetate are obtained; and (5) the oil phase products obtained in Step (4) and water are boiled and rectified, C8 olefin is obtained from the top of the tower in the form of azeotrope and sec-butyl acetate is obtained from the bottom of the tower. The method provided by the invention can obtain relatively high yield of sec-butyl acetate and can obtain sec-butyl acetate and recycle acetic acid at a relatively high purity.

The utility model relates to a method which utilizes a vapour permeation membrane to separate dimethyl carbonate from methanol azeotrope. Saturated vapour at the temperature of 64 to 120 DEG C and with the pressure of 0.10 to 0.6 MPa is sent into a membrane separator and is contacted with a separation membrane, the downstream side of the membrane separator keeps the vacuum degree at 4 to 200 mmHg by vacuum pumping, the dimethyl carbonate first passes through a concentration membrance filter at the permeation side of the membrane and is condensed into liquid under the condition of vacuum and low pressure, the liquid mixture directly enters into an atmospheric rectifying column, dimethyl carbonate with more than or equal to ninety nine point five percent of content is produced from the bottom of the column, and high-concentration methanol is produced from the interception side of the membrane separator and enters into next technique unit. The separation membrane is an organic composite membrane, an organic and mineral composite membrane or a mineral membrane which can preferentially permeate dimethyl carbonate, and the method has the advantages of simple technique and low energy consumption; the throughput of the permeation of the membrane is increased, and the area of the membrane is reduced; safety and reliability are increased, and the purity of dimethyl carbonate is increased as well.

Disclosed herein are azeotrope compositions comprising 1,2,3,3,3-pentafluoropropene and hydrogen fluoride. The azeotrope compositions are useful in processes to produce and in processes to purify 1,2,3,3,3-pentafluoropropene. Additionally, disclosed herein are azeotrope and near-azeotrope compositions comprising 1,1,1,2,3,4,4,5,5,5-decafluoropentane and hydrogen fluoride.

The invention discloses a method for synthesizing poly (ethylene glycol) methyl ether methacrylate. Methyl methacrylate and PGME are synthesized to generate the poly (ethylene glycol) methyl ether methacrylateby through the ester exchange reaction. The catalyst used in the ester exchange reaction is a base catalyst and has high catalytic activity; an inhibitive substance is added in the reaction system to avoid the polyreaction in the process of reaction and air is put into the reaction system; the reaction temperature is moderate and is between 80 and 85 DEG C; the reaction side product of methanol and a reaction medium form an azeotrope which is taken out of the reaction system, thereby ensuring that the reaction is done completely. The method quantificationally converts the PGME into the poly (ethylene glycol) methyl ether methacrylate, has esterification rate close to 100 percent, avoids the polyreaction and other side reactions, has simple steps and is suitable for the industrial production.

The invention discloses a method for continuously extracting, rectifying and separating mixed alcohols from water, relates to a chemical separating method, and in particular to a method for continuously extracting, rectifying and separating mixed alcohols such as aqueous mixtures of ethanol, n-propyl alcohol, isobutyl alcohol and the like. According to the method, extractive distillation and common rectifying are combined together, and a multi-column combined step-by-step separating method is adopted to separate mixed alcohols from water step by step and recycle components with high purity. The method comprises steps of: with ethylene glycol as an extraction agent, separating the mixed alcohols from water in an extractive rectifying column B1, wherein the column B1 adopts normal pressure rectification, the reflux ratio is 1:1-10:1, the mixed alcohols can be get from the column top, and a mixture of a solvent and water can be get from the column bottom; recovering most of the solvent from a solvent recovering column B4 and recycling the solvent; and effectively separating the mixed alcohols through columns B2 and B3. According to the method, extractive distillation and common rectifying are combined together, the extraction agent is used to avoid the azeotrope of alcohols and water, and continuous separation of multiple columns are adopted to recover the components with high purity step by step, so that the method has high economic and environmental benefits.

Foam-forming compositions containing azeotropic or azeotrope-like mixtures containing cis-1,1,1,4,4,4-hexafluoro-2-butene are disclosed. The foam-forming composition contains (a) an azeotropic or azeotrope-like mixture of cis-1,1,1,4,4,4-hexafluoro-2-butene with methyl formate, 1,1,1,3,3-pentafluorobutane, trans-1,2-dichloroethylene, pentane, isopentane, cyclopentane, HFC-245fa, or dimethoxymethane; and (b) an active hydrogen-containing compound having two or more active hydrogens. Also disclosed is a closed-cell polyurethane or polyisocyanurate polymer foam prepared from reaction of an effective amount of the foam-forming composition with a suitable polyisocyanate. Also disclosed is a process for producing a closed-cell polyurethane or polyisocyanurate polymer foam by reacting an effective amount of the foam-forming composition with a suitable polyisocyanate.

Provided are azeotropic and azeotrope-like compositions of 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) and hydrogen fluoride (HF). Such azeotropic and azeotrope-like compositions are useful as intermediates in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf).