US3282801A - Extractive distillation of tetrafluoroethylene with an oxygenated hydrocarbon - Google Patents

Extractive distillation of tetrafluoroethylene with an oxygenated hydrocarbon Download PDF

Info

Publication number
US3282801A
US3282801A US256520A US25652063A US3282801A US 3282801 A US3282801 A US 3282801A US 256520 A US256520 A US 256520A US 25652063 A US25652063 A US 25652063A US 3282801 A US3282801 A US 3282801A
Authority
US
United States
Prior art keywords
tetrafluoroethylene
extractive distillation
distillation
class consisting
fluorocarbons
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US256520A
Other languages
English (en)
Inventor
Wiist Herbert Albert
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
EIDP Inc
Original Assignee
EI Du Pont de Nemours and Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to NL131714D priority Critical patent/NL131714C/xx
Application filed by EI Du Pont de Nemours and Co filed Critical EI Du Pont de Nemours and Co
Priority to US256520A priority patent/US3282801A/en
Priority to DEP33431A priority patent/DE1295543B/de
Priority to FR962672A priority patent/FR1381844A/fr
Priority to NL6400982A priority patent/NL6400982A/xx
Priority to BE643472A priority patent/BE643472A/xx
Priority to GB5155/64A priority patent/GB1034894A/en
Application granted granted Critical
Publication of US3282801A publication Critical patent/US3282801A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C17/00—Preparation of halogenated hydrocarbons
    • C07C17/38—Separation; Purification; Stabilisation; Use of additives
    • C07C17/383—Separation; Purification; Stabilisation; Use of additives by distillation
    • C07C17/386—Separation; Purification; Stabilisation; Use of additives by distillation with auxiliary compounds
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S62/00—Refrigeration
    • Y10S62/918—Halocarbon

Definitions

  • the process of the present invention relates to the separation of fluorocarbons, and, more particularly, to the extractive distillation of tetrailuoroethylene.
  • One of the preferred methods of preparing tetrafiuoroethylene is by pyrolysis of chlorodifluoromethane at temperatures above 700 C., as disclosed in greater detail in US. 2,551,573, issued to Downing et al. on May 8, 1951.
  • the Downing et a1. method results in the production of a large number of fluorocarbons in addition to tetrafluoroethylene.
  • These compounds include hexafluoropropylene, perfluorocyclobutane, trifluorometihane, difluoromet'hane, chlorotrifluoromethane, perfluoroisobutylene, dichlorodifluoromethane, chlorotrifluoroethylene, dichlorotetrafiuoroethane, chlorotetrafluoroethane, chlorohexafluoropropane, a homologous series of compounds (11 up to 13) and a number of other compounds which have not been completely identified.
  • tetrafluoroethylene is produced by pyrolysis of brornodifluoromethane.
  • the pyrolysis of the bromodifi-uoromethane produces a large number of fluorocarbons in addition to tetrafluoroethylene.
  • the p-yrolysate contains a number of compounds which form azeotropes with tetrafluoroethylene or boil so close to tetrafluoroe-thylene that separation by direct distillation is difiicult.
  • R OH, R2OR3, R OOR5, and RsC ⁇ where R to R are saturated aliphatic or aromatic hydrocarbon radicals, which are liquidat distillation conditions, and, in particular, those which contain up to 12 carbon atoms.
  • the process of the present invention is based on the discovery that the volatility of fiuorocarbons boiling close to tetrafluoroethylene, which generally have from 1 to 2 carbon atoms, or form azeotropes with tetrafiuoroethylene, is so changed by the addition of the extractive distillation agents of the present invention, that the separation of these groups of compounds becomes a matter of simple distillation. Additionally, it was surprisingly found that these oxygenated hydrocarbons do not react with the reactive fluorocarbons separated by the process of the present invention, such as tetra-fiuoro ethylene.
  • Examples of azeotropes of perfluorocarbons and fluorocarbons separated by the extractive distillation of the present invention are tetrafluoroethylene and difluoromethane, and tetrafiuoroethylene and trifluoromethane.
  • Most of the close boiling fluorocarbon and perfluorocarbon compounds will 'be apparent from any table listing the physical properties of fluorocarbon and perfluorocarbon compounds, an example of which is pentafluoroethane and tetrafluoroethylene.
  • the process of the present invention is of particular utility in combination with processes for the preparation of tetrafluoroethylene, which is prepared by the pyrolysis of chlorodifiuoromethane, bromodifluoromethane or by inorganic and organic [fluoride arc processes known in the art.
  • the prefer-red extractive distillation agents of the present invention are volatile hydrocarbon alcohols, ethers, esters and ketones which are liquid under distillation conditions and include methanol, ethanol, propanol, isopropanol, butanol, isobutano-l, tert-butyl alcohol, decanol, phenol, benzyl alcohol, o-cres-ol, dimethyl ether, diethyl ether, methyl ethyl ether, methyl propyl ether, methyl phenyl ether, ethyl benzyl ether, acetone, methyl ethyl ketone, diethyl ketone, acetophenone, propi'oplaenone, methyl acetate, ethyl formate, methyl propionate, ethyl acetate, propyl formate, etc.
  • the quantity of the extractive distillation agent to be employed can be varied over a wide range. Even the addition of small quantities of the extractive distillation agent will significantly affect the volatility. In order to readily facilitate the separation of the higher boiling fiuoroinated hydrocarbons obtained from the pyrolysis, after removal of starting material and tetrafluoroethylene it is preferred to employ from 1 to 25 times the weight of the extractive distillation agent as compared to the weight of the higher boiling fluorocarbons.
  • the relative volatilities of the components of the mixture illustrated in the tables below were determined using acetone as the extractive distillation agent.
  • Table III a pressure of 125 p.s.i.a. and a temperature of 63.5 C. were employed.
  • the mole percentage of acetone in the liquid was 79.0 and the mole percentage of acetone in the vapor was 10.3.
  • Table IV a pressure of 60.5 p.s.i.a. and a temperature of 768 C. were employed.
  • the mole percentage of the acetone'in the liquid was 93.0 and the mole percentage of the acetone in the vapor was 15.9.
  • Tetrafluoroethylene is taken as the most volatile component.
  • Example I Crude tetrafluoroethylene, having the following composition.
  • Example I1 Crude tetrafluoroethylene, having the following composition Mol percent was fed vapor phase into a 43" long, 1" diameter packed column (35 40 theoretical plates) operating at atmospheric pressure, 25" up from the base at a rate of 400 g./hr. Acetone at 70 C. was fed from the top of the column at 600 g./ hr. Reflux was at an approximate ratio of 1:1. Temperature of the column ranged from 76 C. at the top of the column to +31 C. at the base. Purity of the tetrafiuoroethylene removed overhead was greater than 99.9 mol percent.
  • the process of the present invention provides a simple, effective and economic method for the recovery of pure tetrafluoroethylene when formed in admixture With other fiuorocarbons, such asare obtained in the pyrolysis of chlorodifluorornethan'e and bromodifiuoromethane.
  • a process for separating tetrafiuoroethylene from fiuorocarbons containing from 1 to 2 carbon atoms and, in addition to fluorine, elements selected from the class consisting of hydrogen and halogen, having atomic numbers from 17 to 53 inclusive in admixture with the tetrafluoroethylene the steps of distilling the mixture, by extractive distillation in the presence of an oxygenated hydrocarbon, liquid at distillation conditions and selected from the class consisting of alcohols, ethers, ketones and esters, said oxygenated hydrocarbons having the general formulas R OH, R OR R COR and R6COOR7, where R to R are radicals selected from the class consisting of saturated aliphatic and aromatic hydrocarbon radicals, and removing the tetrafiuoroethylene as an overhead from the distillation zone.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
US256520A 1963-02-06 1963-02-06 Extractive distillation of tetrafluoroethylene with an oxygenated hydrocarbon Expired - Lifetime US3282801A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
NL131714D NL131714C (en)) 1963-02-06
US256520A US3282801A (en) 1963-02-06 1963-02-06 Extractive distillation of tetrafluoroethylene with an oxygenated hydrocarbon
DEP33431A DE1295543B (de) 1963-02-06 1964-01-22 Verfahren zur Abtrennung von Tetrafluoraethylen aus den bei der Pyrolyse von Chlordifluoraralkan oder Bromdifluormethan anfallenden Gemischen
FR962672A FR1381844A (fr) 1963-02-06 1964-02-05 Procédé de distillation des fluorocarbures
NL6400982A NL6400982A (en)) 1963-02-06 1964-02-06
BE643472A BE643472A (en)) 1963-02-06 1964-02-06
GB5155/64A GB1034894A (en) 1963-02-06 1964-02-06 Improvements in or relating to fluorocarbon separation

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US256520A US3282801A (en) 1963-02-06 1963-02-06 Extractive distillation of tetrafluoroethylene with an oxygenated hydrocarbon

Publications (1)

Publication Number Publication Date
US3282801A true US3282801A (en) 1966-11-01

Family

ID=22972533

Family Applications (1)

Application Number Title Priority Date Filing Date
US256520A Expired - Lifetime US3282801A (en) 1963-02-06 1963-02-06 Extractive distillation of tetrafluoroethylene with an oxygenated hydrocarbon

Country Status (6)

Country Link
US (1) US3282801A (en))
BE (1) BE643472A (en))
DE (1) DE1295543B (en))
FR (1) FR1381844A (en))
GB (1) GB1034894A (en))
NL (2) NL6400982A (en))

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3326780A (en) * 1964-12-29 1967-06-20 Du Pont Extractive distillation of hexafluoropropylene epoxide mixture
US3391201A (en) * 1964-12-30 1968-07-02 Ciba Ltd Process for separating mixtures of cycloaliphatic fluorine compounds
US3720587A (en) * 1971-08-02 1973-03-13 Airco Inc Separating 1-chloro-2,2,2-trifluoro-ethyl difluoromethyl ether from 1-chloro-2,2,2-trifluoroethyl difluorochloro-methyl ether by azeotropic distillation
US3989601A (en) * 1975-09-08 1976-11-02 The Dow Chemical Company Purification of 1,1,1-trichloroethane by extractive distillation
US4134796A (en) * 1977-11-17 1979-01-16 Asahi Glass Company Ltd. Method of purifying hexafluoropropylene oxide
FR2409973A1 (fr) * 1977-11-28 1979-06-22 Asahi Glass Co Ltd Procede de purification de l'oxyde d'hexafluoropropylene
US4898645A (en) * 1987-09-01 1990-02-06 Hoechst Aktiengesellschaft Process for the production of pure tetrafluoroethylene
US5049241A (en) * 1990-03-27 1991-09-17 E. I. Du Pont De Nemours And Company Extractive distillation
US5626023A (en) * 1995-02-16 1997-05-06 Praxair Technology, Inc. Cryogenic rectification system for fluorine compound recovery using additive liquid
US5830325A (en) * 1995-02-01 1998-11-03 E. I. Du Pont De Nemours And Company Separating and removing 1, 1, 1-trifluoroethane by using azeotropic distillation
US5919340A (en) * 1994-08-17 1999-07-06 Daikin Industries Ltd. Process for recovering pentafluoroethane
US6047560A (en) * 1997-03-12 2000-04-11 Showa Denko K.K. Process for separating pentafluoroethane and 1,1,1-trifluoroethane
US6179967B1 (en) * 1993-05-25 2001-01-30 Showa Denko K.K. Purification process of pentrafluoroethane

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2638650C2 (de) * 1976-08-27 1982-11-25 Hoechst Ag, 6000 Frankfurt Verfahren zur Abtrennung von Tetrafluoräthylen aus Gasgemischen

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2339160A (en) * 1940-08-02 1944-01-11 Shell Dev Distillation process
US2357028A (en) * 1943-08-04 1944-08-29 Shell Dev Solvent extraction process
US2456184A (en) * 1946-04-17 1948-12-14 Du Pont Purification of tetrachlorethylene
US2473911A (en) * 1943-07-19 1949-06-21 Ici Ltd Production of fluorocarbons
US2604439A (en) * 1952-07-22 Distillation of
US3101304A (en) * 1960-04-28 1963-08-20 Du Pont Distillation process for fluorocarbons
US3152051A (en) * 1962-03-12 1964-10-06 Pennsalt Chemicals Corp Separation of a mixture containing tetrafluoroethylene and fluoroform by extractive distillation

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1293690A (fr) * 1960-04-28 1962-05-18 Du Pont Procédé de distillation extractive de carbures fluorés

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2604439A (en) * 1952-07-22 Distillation of
US2339160A (en) * 1940-08-02 1944-01-11 Shell Dev Distillation process
US2473911A (en) * 1943-07-19 1949-06-21 Ici Ltd Production of fluorocarbons
US2357028A (en) * 1943-08-04 1944-08-29 Shell Dev Solvent extraction process
US2456184A (en) * 1946-04-17 1948-12-14 Du Pont Purification of tetrachlorethylene
US3101304A (en) * 1960-04-28 1963-08-20 Du Pont Distillation process for fluorocarbons
US3152051A (en) * 1962-03-12 1964-10-06 Pennsalt Chemicals Corp Separation of a mixture containing tetrafluoroethylene and fluoroform by extractive distillation

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3326780A (en) * 1964-12-29 1967-06-20 Du Pont Extractive distillation of hexafluoropropylene epoxide mixture
US3391201A (en) * 1964-12-30 1968-07-02 Ciba Ltd Process for separating mixtures of cycloaliphatic fluorine compounds
US3720587A (en) * 1971-08-02 1973-03-13 Airco Inc Separating 1-chloro-2,2,2-trifluoro-ethyl difluoromethyl ether from 1-chloro-2,2,2-trifluoroethyl difluorochloro-methyl ether by azeotropic distillation
US3989601A (en) * 1975-09-08 1976-11-02 The Dow Chemical Company Purification of 1,1,1-trichloroethane by extractive distillation
US4134796A (en) * 1977-11-17 1979-01-16 Asahi Glass Company Ltd. Method of purifying hexafluoropropylene oxide
FR2409973A1 (fr) * 1977-11-28 1979-06-22 Asahi Glass Co Ltd Procede de purification de l'oxyde d'hexafluoropropylene
US4898645A (en) * 1987-09-01 1990-02-06 Hoechst Aktiengesellschaft Process for the production of pure tetrafluoroethylene
US5049241A (en) * 1990-03-27 1991-09-17 E. I. Du Pont De Nemours And Company Extractive distillation
US6179967B1 (en) * 1993-05-25 2001-01-30 Showa Denko K.K. Purification process of pentrafluoroethane
US5919340A (en) * 1994-08-17 1999-07-06 Daikin Industries Ltd. Process for recovering pentafluoroethane
US5830325A (en) * 1995-02-01 1998-11-03 E. I. Du Pont De Nemours And Company Separating and removing 1, 1, 1-trifluoroethane by using azeotropic distillation
US5626023A (en) * 1995-02-16 1997-05-06 Praxair Technology, Inc. Cryogenic rectification system for fluorine compound recovery using additive liquid
US6047560A (en) * 1997-03-12 2000-04-11 Showa Denko K.K. Process for separating pentafluoroethane and 1,1,1-trifluoroethane

Also Published As

Publication number Publication date
NL131714C (en))
FR1381844A (fr) 1964-12-14
BE643472A (en)) 1964-08-06
GB1034894A (en) 1966-07-06
DE1295543B (de) 1969-05-22
NL6400982A (en)) 1964-08-07

Similar Documents

Publication Publication Date Title
US3282801A (en) Extractive distillation of tetrafluoroethylene with an oxygenated hydrocarbon
US3101304A (en) Distillation process for fluorocarbons
US5445716A (en) Separation of ethanol from isopropanol by extractive distillation
RU2101271C1 (ru) Способ выделения пентафторэтана из смеси с хлорпентафторэтаном
EP0749407B1 (en) Separating and removing impurities from tetrafluoroethanes by using extractive distillation
US2559519A (en) Extractive distillation of alcohols with glycol ethers
US3349009A (en) Separation of hydrocarbons by distilling with a fluorocarbon
EP0935593B1 (en) Process for the purification of 1,1-difluoroethane
US4584063A (en) Separation of acetone from methanol by extractive distillation
US2478362A (en) Distillation process for separating products of perchloro-ethylene fluorination
US5129997A (en) Process for the recovery of mixtures of chlorotetrafluoroethane and octafluorocyclobutane
US4092257A (en) Constant boiling admixtures of toluene/perfluoro-n-heptane
US4666563A (en) Separation of isopropyl ether from isopropanol and water by extractive distillation
US2593451A (en) Dehydrochlorination of polychloroethanes
US4501645A (en) Separation of methanol from acetone by extractive distillation
US3846332A (en) Azeotropes of 1-chloro-2,2,2-trifluoroethyl difluoromethyl ether with acetone, methyl ethylketone and tetrahydrofuran
EP0743933B1 (en) Process for separating pentafluoroethane from a mixture comprising halogenated hydrocarbons and chloropentafluoroethane
US3404189A (en) Preparation of fluorinated alkyl iodides by selective telomerization
US5919340A (en) Process for recovering pentafluoroethane
US4549938A (en) Separation of methanol from methyl acetate by extractive distillation
US3720587A (en) Separating 1-chloro-2,2,2-trifluoro-ethyl difluoromethyl ether from 1-chloro-2,2,2-trifluoroethyl difluorochloro-methyl ether by azeotropic distillation
JP2827912B2 (ja) ペンタフルオロエタンの製造方法
US5723429A (en) Azeotropic or azeotrope-like compositions of tetrafluoroethane and chlorotetrafluoroethane
US4308410A (en) Production of chloroprene
KR20010041583A (ko) 과플루오로시클로부탄의 정제 방법