1142results about "Preparation by halogen replacement" patented technology

A method for preparing 2,3,3,3-tetrafluoroprop-1-ene comprising (a) providing a starting composition comprising at least one compound having a structure selected from Formulae I, II and III:

CX₂═CCl—CH₂X  (Formula I)

CX₃—CCl═CH₂  (Formula II)

CX₃—CHCl—CH₂X  (Formula III)

• • wherein X is independently selected from F, Cl, Br, and I, provided that at least one X is not fluorine;

(b) contacting said starting composition with a first fluorinating agent to produce a first intermediate composition comprising 2-chloro-3,3,3-trifluoropropene and a first chlorine-containing byproduct; (c) contacting said first intermediate composition with a second fluorinating agent to produce a second intermediate composition comprising 2-chloro-1,1,1,2-tetrafluoropropane and a second chlorine-containing byproduct; and (d) catalytically dehydrochlorinating at least a portion of said 2-chloro-1,1,1,2-tetrafluoropropane to produce a reaction product comprising 2,3,3,3-tetrafluoroprop-1-ene.

One or more materials selected from 1,1,1,3,3-pentachloropropane, 1,1,3,3-tetrachloropropene and 1,3,3,3-tetrachloropropene are used as the specific materials described above. Before submitting the materials and HF to a fluorination reaction, almost all water is removed from them.To continuously manufacture useful intended products efficiently as well as to prevent deactivation of the catalyst and the accumulation of organic substances with high boiling points when manufacturing said useful 1,1,1,3,3-pentafluoropropane and/or 1-chloro-3,3,3-trifluoropropene, by fluorinating the specific materials with HF in the presence of a catalyst.

The invention provides an economic process for the manufacture of 1,3,3,3-tetrafluoropropene (HFC-1234ze) by a two stage process. A hydrofluorination of 1-chloro-3,3,3-trifluoropropene (HCFC-1233zd) into 1-chloro-1,3,3,3-tetrafluoropropane (HCFC-244fa) and 1,1,1,3,3-pentafluoropropane (HFC-245fa) is conducted, followed by the dehydrochlorination of HCFC-244fa and dehydrofluorination of HFC-245fa into HFC-1234ze.

The present invention relates to an improved method for manufacturing 2-chloro-3,3,3,-trifluoropropene (HCFC-1233xf) by reacting 1,1,2,3-tetrachloropropene, 1,1,1,2,3-pentachloropropane, and/or 2,3,3,3-tetrachloropropene with hydrogen fluoride, in a vapor phase reaction vessel in the presence of a vapor phase fluorination catalyst and stabilizer. HCFC-1233xf is an intermediate in the production of 2,3,3,3-tetrafluoropropene (HFO-1234yf) which is a refrigerant with low global warming potential.

This invention relates a process for the manufacture of the HFO trans-1,3,3,3-tetrafluoropropene (HFO trans-1234ze). More particularly, the invention pertains to a process for the manufacture of the HFO trans-1234ze by first dehydrofluorinating 1,1,1,3,3-pentafluoropropane to thereby produce a mixture of cis-1,3,3,3-tetrafluoropropene, trans-1,3,3,3-tetrafluoropropene and hydrogen fluoride. Then optionally recovering hydrogen fluoride and then recovering trans-1,3,3,3-tetrafluoropropene.

The invention provides an economic process for the manufacture of 1,3,3,3-tetrafluoropropene (HFO-1234ze) by a two stage process. A vapor phase hydrofluorination of 1-chloro-3,3,3-trifluoropropene (HCFC-1233zd) into 1-chloro-1,3,3,3-tetrafluoropropane (HCFC-244fa) and/or 1,1,1,3,3-pentafluoropropane (HFC-245fa) is conducted, followed by the thermal dehydrochlorination of HCFC-244fa and dehydro fluorination of HFC-245fa into HFO-1234ze in the presence of a catalyst which comprises one or more of alkali metal halides, alkaline earth metal halides, halogenated metal oxides, zero oxidation state metals, zinc halides, palladium halides, and activated carbon.

Disclosed is process for the production of (E) 1-chloro-3,3,3-trifluoropropene (HCFO-1233zd(E)) by conducting a continuous reaction without the use of a catalyst. Also disclosed is an integrated system for producing hydrofluoro olefins, particularly 1233zd(E). The manufacturing process includes six major unit operations: (1) a fluorination reaction of HCC-240fa (in continuous or semi-batch mode) using HF with simultaneous removal of by-product HCl and the product 1233zd(E); (2) recycle of unreacted HCC-240fa and HF together with under-fluorinated by-products back to (1); (3) separation and purification of by-product HCl; (4) separation of excess HF back to (1); (5) purification of final product, 1233zd(E); and (6) isomerization of by-product 1233zd(Z) to 1233zd(E) to maximize the process yield.

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.

Disclosed is a process for the synthesis of 1,3,3,3-tetrafluoropropene that comprises, in one preferred embodiment, providing a compound of the formula CF₃CH₂CHFX, wherein X is a selected from the group consisting of chlorine, bromine and iodine, and exposing said compound to reaction conditions effective to convert said compound to 1,3,3,3-tetrafluoropropene. Other processes for forming 1,3,3,3-tetrafluoropropene are also disclosed.

A process for the manufacture of CF₃CH═CHF and/or CF₃CH═CF₂ is disclosed. The process involves involves (a) reacting HF and at least one halopropene of the formula CX₃CCI═CCIX (where each X is independently F or CI) to produce a product including both CF₃CCI═CF₂ and CF₃CHCICF₃; (b) reacting CF₃CCI═CF₂ and/or CF₃CHCICF₃ produced in (a) with hydrogen to produce a product including CF₃CH₂CHF₂ and/or CF₃CH₂CF₃; (c) dehydrofluorinating CF₃CH₂CHF₂ and/or CF₃CH₂CF₃ produced in (b) to produce a product comprising CF₃CH═CHF and/or CF₃CH═CF₂; and (d) recovering CF₃CH═CHF and/or CF₃CH═CF₂ from the product produced in (c). In (a), the CF₃CCI═CF₂ and CF₃CHCICF₃ are produced in the presence of a fluorination catalyst comprising at least one chromium-containing component selected from (i) a crystalline alpha-chromium oxide where at least 0.05 atom % of the chromium atoms in the alpha-chromium oxide lattice are replaced by divalent copper, and (ii) a chromium-containing composition of (i) which has been treated with a fluorinating agent.

An integrated process for the manufacture of HFO trans-1,3,3,3-tetrafluoropropene (HFO trans-1234ze) by first catalytically dehydrofluorinating 1,1,1,3,3-pentafluoropropane to thereby produce a mixture of cis-1,3,3,3-tetrafluoropropene, trans-1,3,3,3-tetrafluoropropene and hydrogen fluoride. Then optionally recovering hydrogen fluoride, catalytically isomerizing cis-1234ze into trans-1234ze, and recovering trans-1,3,3,3-tetrafluoropropene.

The invention relates to the preparation of 1-chloro-1,1,3,3,3-pentafluoropropane (HCFC-235fa), useful as an intermediate in the production of 1,1,1,3,3-pentafluoropropane (HFC-245fa). The invention further relates to a process for the preparation of HFC-245fa comprising reacting HCFC-235fa with hydrogen in the presence of a reduction catalyst wherein the said HCFC-235fa is prepared by reacting CCl3CHCCl3 with hydrogen fluoride in the presence of fluorination catalyst in either the liquid phase or the vapor phase.

According to the first characteristic of the present invention, there is provided a production process for 1,3,3,3-tetrafluoropropene including: the first step of reacting 1,1,1,3,3-pentachloropropane with hydrogen fluoride thereby obtaining 1-chloro-3,3,3-trifluoropropene; and the second step of reacting 1-chloro-3,3,3-trifluoropropene obtained in the first step with hydrogen fluoride in a gaseous phase in the presence of a fluorination catalyst. According to the second characteristic of the present invention, there is provided a dehydration process including bringing 1,3,3,3-tetrafluoropropene containing at least water into contact with zeolite.

The invention discloses a process for preparing 1, 1, 1, 3-HFO-1234ze, which resolves the problem of low selectivity of HFO-1234ze. The invention takes 1, 1, 1, 3, 3-HCC-240fa as raw material, including the following steps that a, placing hydrogen fluoride (HF) and HCC-240fa into a reactor to react with fluorination catalyst, b, distilling and detaching the produced fluid in step a which flows into a distillation tower, the tower bottom components of 1, 1, 1, 3, 3-HCC-240fa, 1-chlorine-3, 3, 3-HCFC-1233zd and hydrogen fluoride recycle to the reactor, the tower top components of hydrogen fluoride and HFO-1234ze enter after-treatment system and obtaining object product HFO-1234ze after processes of deoxidation, dehydration and distillation and the like. The invention is mainly used to prepare HFO-1234ze.

The invention provides an economic process for the manufacture of the hydrofluorocarbon 1,1,3,3,3-pentafluoropropene (HFC-1225zc). HFC-1225zc can be made from the dehydrochlorination of 1-chloro-1,1,3,3,3-pentafluoropropane (HCFC-235fa). Alternatively, HFC-1225zc can also be made from the dehydrofluorination of 1,1,1,3,3,3-hexafluoropropane (HFC-236fa). HFC-1225zc) is a compound that has the potential to be used as a low Global Warming Potential refrigerant, blowing agent, aerosol propellant, or solvent.

A method for producing fluorinated organic compounds, including hydrofluoropropenes, which preferably comprises converting at least one compound of formula (I):

CF₃(—CX²X²)_nCX¹═H₂  (I)

to at least one compound of formula (II):

CF₃(CX²X²)_nCX¹═H₂  (II),

where X¹ is Cl, Br or I, each X² is independently selected from the group consisting of H, Cl, F, Br or J, and n is 0, 1, or 2.