Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C17/00—Preparation of halogenated hydrocarbons
  • C07C17/35—Preparation of halogenated hydrocarbons by reactions not affecting the number of carbon or of halogen atoms in the reaction
  • C07C17/358—Preparation of halogenated hydrocarbons by reactions not affecting the number of carbon or of halogen atoms in the reaction by isomerisation

Definitions

• the disclosure herein relates in general to processes for the catalytic isomerization between E and Z isomers of 1 ,2,3,3,3-pentafluoropropene (HFC-1225ye).
• HFC-1225ye 1 ,2,3,3,3-pentafluoropropene
• the production of other hydrofluorocarbons for use in applications such as solvents, blowing agents, cleaning agents, aerosol propellants, heat transfer media, dielectrics, fire extinguishants and power cycle working fluids has also been the subject of considerable interest.
• HFC-1225ye having zero ozone depletion and a low global warming potential, has been identified as a potential refrigerant.
• HFC- 1225ye can also find use in other applications such as solvents, cleaning agents, foam expansion agents, aerosol propellants, heat transfer media, dielectrics, fire extinguishing agents, stehlants and power cycle working fluids.
• HFC-1225ye may also be used to make polymers.
• HFC-1225ye may exist as one of two configurational isomers, E or Z, which boil at different temperatures.
• HFC-1225ye may be preferably used as the Z-isomer or the E-isomer or a mixture thereof. It is known that Z-HFC-1225ye is thermodynamically more stable than E- HFC-1225ye.
• the Z/E ratio of 1 ,2,3,3,3- pentafluoropropene can be increased by decreasing the temperature of the HFC-1225ye in the vapor phase in presence of aluminum catalysts, or that the Z/E ratio can be decreased by increasing the temperature of the HFC-1225ye in the vapor phase in the presence of aluminum catalysts.
• a process has been provided to increase the ZIE ratio of 1 ,2,3,3,3- pentafluoropropene.
• the process comprises: contacting a starting material comprising 1 ,2,3,3,3-pentafluoropropene in the vapor phase with an aluminum catalyst selected from the group consisting of fluorided alumina and high surface area amorphous aluminum fluoride to obtain a final product comprising 1 ,2,3,3,3-pentafluoropropene, wherein the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene in the final product is increased relative to the ZIE ratio of 1 ,2,3,3,3-pentafluoropropene in said starting material.
• a process has also been provided to decrease the ZIE ratio of 1 ,2,3,3,3- pentafluoropropene.
• the process comprises: contacting a starting material comprising 1 ,2,3,3,3-pentafluoropropene in the vapor phase with an aluminum catalyst to obtain a final product comprising 1 ,2,3,3,3- pentafluoropropene, wherein the ZIE ratio of the 1 ,2,3,3,3- pentafluoropropene in the final product is decreased relative to the ZIE ratio of 1 ,2,3,3,3-pentafluoropropene in said starting material.
• HFC-1225ye may exist as one of two configurational isomers, E or Z.
• HFC-1225ye (with no isomer designation) as used herein refers to either of the isomers, E-1225ye (CAS reg no. 5595-10-8) or Z-1225ye (CAS reg. no. 5528-43-8), as well as any combinations or mixtures of such isomers.
• HFC-1225ye may be prepared by methods known in the art, such as those described in US Patent Nos. 5,396,000, 5,679,875, 6,031 ,141 , and 6,369,284.
• the term "isomehzation process” is intended to mean any process by which the Z/E ratio of HFC-1225ye is changed, either increased or decreased.
• ZIE ratio is intended to mean the molar ratio of Z isomer to E isomer of an olefin.
• ZIE ratio of HFC- 1225ye is intended to mean the molar ratio of Z-1225ye to E-1225ye.
• an elevated temperature is intended to mean a temperature higher than room temperature.
• the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion.
• a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
• “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).
• the present disclosure provides a process for increasing the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene in a final product relative to the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene in a starting material.
• the process comprises contacting the starting material comprising 1 ,2,3,3,3-pentafluoropropene in the vapor phase with an aluminum catalyst to obtain a final product comprising 1 ,2,3,3,3-pentafluoropropene.
• the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene in the final product is increased relative to the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene in said starting material.
• the HFC-1225ye in the starting material is either E-HFC-1225ye or a mixture of E-HFC-1225ye and Z-HFC-1225ye.
• the HFC-1225ye in the starting material has a lower ZIE ratio than the HFC-1225ye in the final product.
• the ZIE ratio of 1 ,2,3,3,3-pentafluoropropene in the final product is at least 10. In another embodiment, the ZIE ratio of 1 ,2,3,3,3-pentafluoropropene in said final product is at least 20. In another embodiment, the ZIE ratio of 1 ,2,3,3,3-pentafluoropropene in the final product is at least 40.
• the contacting is conducted at a temperature of from about -20 0 C to about 150 0 C. In another embodiment, the contacting is conducted at a temperature of from about -10 0 C to about 100 0 C. In another embodiment, the contacting is conducted at a temperature of from about 0 0 C to about 50 0 C. In another embodiment, the contacting is conducted at about ambient, i.e., room temperature.
• the present disclosure also provides a process for decreasing the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene in a final product relative to the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene in a starting material.
• the process comprises contacting the starting material comprising
• 1 ,2,3,3,3-pentafluoropropene in the final product is decreased relative to the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene in said starting material.
• the HFC-1225ye in the starting material is either Z-HFC-1225ye or a mixture of E-HFC-1225ye and Z-HFC-1225ye.
• the HFC-1225ye in the starting material has a higher ZIE ratio than the HFC-1225ye in the product.
• the contacting is conducted at an elevated temperature.
• the contacting is conducted at a temperature of from about 300 0 C to about 450 0 C.
• the catalyst is an aluminum catalyst which can be used in vapor phase reactions.
• the process occurs in the vapor phase, i.e., the 1 ,2,3,3,3-pentafluoropropene is in the vapor phase.
• the catalyst may be selected from the group consisting of high surface area amorphous aluminum fluoride and fluohded alumina.
• the catalyst may be prepared by treatment of aluminum oxide (also known as alumina or AI2O3) with HF at elevated temperature (as described in Example 1 ).
• a high surface area amorphous aluminum fluoride may be prepared as described in US 2004/0052649 A1.
• the Z/E ratio of the 1 ,2,3,3,3-pentafluoropropene in said product is at least 10. In another embodiment where the Z/E ratio is either increased or decreased, the ZIE ratio of 1 ,2,3,3,3-pentafluoropropene in said product is at least 20. In another embodiment where the ZIE ratio is either increased or decreased, the Z/E ratio of 1 ,2,3,3,3-pentafluoropropene in said product is at least 40. In either process where the ZIE ratio of the
• the contact time for 1 ,2,3,3,3-pentafluoropropene with the catalyst is not critical. In one embodiment, the contact time may range from about 0.01 seconds to 100 seconds. In another embodiment, the contact time may range from about 5 seconds to about 60 seconds.
• the pressure employed in the isomerization process can be subatmospheric, atmospheric or superatmospheric. In one embodiment, the isomerization pressure is near atmospheric. In another embodiment, the isomerization pressure is autogenous. In certain embodiments of either process where the ZIE ratio of the 1 ,2,3,3,3-pentafluoropropene is increased or decreased, the contacting may occur in any suitable vapor phase reaction vessel. In one particular embodiment, the reaction vessel is a tube packed with catalyst through which the gaseous HFC-1225ye may flow.
• the reaction vessel for the isomerization process and its associated feed lines, effluent lines, and associated units used in applying the disclosed processes should be constructed of materials resistant to corrosion.
• Typical materials of construction include stainless steels, in particular of the austenitic type, the well-known high nickel alloys, such as nickel-copper alloys commercially available under the trademark Monel ® , nickel-based alloys commercially available under the trademark Hastelloy ® and nickel- chromium alloys commercially available under the trademark Inconel ® , and copper-clad steel.
• the ratio of isomers will depend on the temperature at which the starting material is allowed to equilibrate. For example, if the E-isomer is desired, and the starting material is the Z-isomer, allowing the starting material to equilibrate at about 350 0 C will produce about 10% E-isomer. In an embodiment wherein the starting material is 10% E-isomer and 90% Z- isomer (which is the case when the two isomers are made at about 350 0 C) the Z-isomer can be increased to 99% by interconverting them at 25°C. Therefore, the equilibrium composition may be approached from either side.
• An InconelTM tube (5/8 inch OD) was filled with 13 cc (8.01 gm) of AI 2 O 3 extrudate ground to 12/20 mesh.
• the temperature of the catalyst bed was raised to 200 0 C for 20 minutes under a flow of nitrogen of 38 seem (6.3 x 10 "7 m 3 /sec).
• the temperature was then raised to 325 0 C for 13 minutes, to 400 0 C for 27 minutes and to 300 0 C for 80 minutes while maintaining the same nitrogen flow.
• the flow of nitrogen was then reduced to 26 seem (4.3 x 10 "7 m 3 /sec) and the flow of HF added at 9 seem (1.5 x 10 "7 m 3 /sec) for 46 minutes.
• the temperature was raised to 325 0 C for 80 minutes, to 35O 0 C for 80 minutes, to 375 0 C for 120 minutes, to 400 0 C for 40 minutes, and to 425 0 C for 53 minutes, all at the same flows.
• the nitrogen flow was reduced to 19 seem (3.2 x 10 "7 m 3 /sec) and the HF increased to 15 seem (2.5 x 10 "7 m 3 /sec) while maintaining the temperature at 425 0 C for 27 minutes.
• the nitrogen flow was reduced to 11 seem (1.8 x 10 "7 m 3 /sec) and the HF increased to 21 seem (3.5 x 10 "7 m 3 /sec) while maintaining the temperature at 425 0 C for 27 minutes.
• the nitrogen flow was reduced to 4 seem (6.7 x 10 "7 m 3 /sec) and the HF increased to 27 seem (4.5 x 10 "7 m 3 /sec) while maintaining the temperature at 425 0 C for 27 minutes.
• the nitrogen flow was ceased and the HF flow increased to 30 seem (5.0 x 10 "7 m 3 /sec) while maintaining the temperature at 425 0 C for 161 minutes.
• the temperature was then cooled to 3O 0 C while under a nitrogen flow of 20 seem (3.3 x 10 "7 m 3 /sec).

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• 2008
  • 2008-08-14 WO PCT/US2008/073089 patent/WO2009026082A1/en not_active Ceased
  • 2008-08-14 US US12/674,974 patent/US20100197980A1/en not_active Abandoned
  • 2008-08-14 CN CN200880103339A patent/CN101842337A/zh active Pending
  • 2008-08-14 JP JP2010521164A patent/JP2010536777A/ja active Pending

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