HK1098737B - Process for the preparation of 1,1,1,3,3-pentafluoro-2-chloropropene and 1,1,1,3,3,3-hexafluoro-2-chloropropane - Google Patents

Description

Process for the preparation of 1, 1,3, 3, 3-pentafluoro-2-chloropropene and 1, 1, 1,3, 3, 3-hexafluoro-2-chloropropane

Technical Field

The present invention relates to the synthesis of 1, 1, 1,3, 3-pentafluoropropane and 1, 1, 1,3, 3, 3-hexafluoropropane.

Background

Various chlorine-containing halocarbons are believed to be detrimental to the earth's ozone layer. Materials with low ozone depletion potential that can be used as effective alternatives are being developed worldwide. For example, hydrofluorocarbon 1, 1, 1, 2-tetrafluoroethane (HFC-134a) is being used as a replacement for dioxydifluoromethane (CFC-12) in refrigeration systems. There is a need for a process for the preparation of halogenated hydrocarbons which provides little or no chlorine. The production of hydrofluorocarbons (i.e., compounds containing only carbon, hydrogen, and fluorine) has been the subject of considerable interest to provide environmentally desirable products for use as solvents, blowing agents, refrigerants, cleaning agents, aerosol propellants, heat transfer media, dielectrics, fire extinguishing agents, and power cycle working fluids. For example, 1, 1, 1,3, 3-pentafluoropropane may be used as a blowing agent, and 1, 1, 1,3, 3, 3-hexafluoropropane may be used as a fire extinguishing agent and a refrigerant.

Summary of The Invention

The present invention provides a process for the preparation of 1, 1, 1,3, 3-pentafluoropropane (HFC-245fa) and 1, 1, 1,3, 3, 3-hexafluoropropane (HFC-236 fa). The process comprises (a) reacting HF with at least one compound of the formula CX₃A halopropene of formula CCl ═ CClX, wherein each X is independently selected from F and Cl, to produce a reaction product comprising CF₃CCl＝CF₂And CF₃CHClCF₃The product of (1), wherein the CF₃CCl＝CF₂And CF₃CHClCF₃Is formed in the presence of a fluorination catalyst comprising at least one composition selected from the group consisting of: (i) containing ZnCr₂O₄And crystalline alpha-chromium oxide; (ii) a composition comprising a zinc halide and alpha-chromium oxide; and (iii) a composition of (i) or (ii) that has been treated with a fluorinating agent (e.g., anhydrous hydrogen fluoride); (b) CF to be generated in (a)₃CCl＝CF₂And CF₃CHClCF₃With hydrogen (H)₂) Optionally in the presence of HF, to form a catalyst comprising CF₃CH₂CHF₂And CF₃CH₂CF₃The product of (a); and (c) recovering CF from the product formed in (b)₃CH₂CHF₂And CF₃CH₂CF₃。

Detailed Description

The present invention provides for the preparation of CF₃CH₂CHF₂(HFC-245fa) and CF₃CH₂CF₃(HFC-236 fa). The HFC-245fa and HFC-236fa can be recovered as separate products and/or as one or more mixtures of the two products.

In step (a) of the process of the present invention, one or more halopropene compound(s) CX are added₃CCl ═ CClX, where each X is independently selected from F and Cl, is reacted with Hydrogen Fluoride (HF) to produce a catalyst comprising CF₃CCl＝CF₂(CFC-1215xc) and CF₃CHClCF₃(HCFC-226 da). Thus, the present invention provides for the preparation of CF from readily available starting materials₃CCl＝CF₂(CFC-1215xc) and CF₃CHClCF₃(HCFC-226 da).

Suitable feedstocks for the process of the present invention include E-and Z-CF₃CCl＝CClF(CFC-1214xb)、CF₃CCl＝CCl₂(CFC-1213xa)、CClF₂CCl＝CCl₂(CFC-1212xa)、CCl₂FCCl＝CCl₂(CFC-1211xa) and CCl₃CCl＝CCl₂(hexachloropropene, HCP) or mixtures thereof.

The preferred starting material for the process of the present invention is CF due to its ready availability₃CCl＝CCl₂(CFC-1213xa) and CCl₃CCl＝CCl₂(hexachloropropene, HCP).

Preferably, HF is reacted with CX₃The reaction of CCl ═ CClX is carried out in the gas phase in a heated tubular reactor. A variety of reactor configurations are possible, including vertical and horizontal reactor orientations, and different ways of contacting the halopropene starting material(s) with HF. Preferably, the HF is substantially anhydrous.

In one embodiment of step (a), the halopropene starting material(s) is/are fed to a reactor containing a fluorination catalyst. The halopropene starting material(s) may be first vaporized and fed into the reactor as a gas.

In another embodiment of step (a), the halopropene starting material(s) may be contacted with HF in a pre-reactor. The prereactor may be empty (i.e. unfilled), but is preferably filled with a suitable packing, for example Monel^TMOr Hastelloy^TMNickel alloy shavings or felts, or otherwise inert to HCl and HF and make CX₃CCl is a material that can be efficiently mixed with HF.

If the halopropene starting material(s) are fed as a liquid to the prereactor, the prereactor is preferably vertically oriented, with the CX being₃CCl ═ CClX enters the top of the reactor, and preheated HF vapor is introduced at the bottom of the reactor.

For the pre-reactor, suitable temperatures are in the range of about 80 ℃ to about 250 ℃, preferably about 100 ℃ to about 200 ℃. Under these conditions, for example, hexachloropropene is converted into a mixture containing predominantly CFC-1213 xa. The feed rate of the feedstock is determined by the length and diameter of the reactor, the temperature and the degree of fluorination desired in the pre-reactor. Slower feed rates at a given temperature will increase contact time and tend to increase the amount of conversion of the starting material, as well as increase the degree of fluorination of the product.

The term "degree of fluorination" means CX₃CCl ═ CClX starting materialThe degree of fluorine atom substitution for the chlorine substituent. For example, CF₃CCl ═ CClF stands for ratio CClF₂CCl＝CCl₂High degree of fluorination, and CF₃CHClCF₃Representative ratio CClF₂CHClCF₃A high degree of fluorination.

The molar ratio of HF fed to the pre-reactor or to the reaction zone of step (a) to halopropene starting material fed in step (a) is typically from about stoichiometric to about 50: 1. The stoichiometric ratio depends on the average degree of fluorination of the halopropene starting material(s) fed to the pre-reactor and is typically based on C₃ClF₅Is performed. For example, if the halopropene is HCP, the stoichiometric ratio of HF to HCP is 5: 1; if the halopropene is CFC-1213xa, the stoichiometric ratio of HF to CFC-1213xa is 2: 1. Preferably, the ratio of HF to halopropene starting material(s) is stoichiometric with respect to each other (based on C)₃ClF₅From about 2 times to about 30: 1. Ratios above 30: 1 are not particularly advantageous. The lower HF to halopropene ratio results in a decrease in the yields of CFC-1215xc and HCFC-226 da. Generally, for a given catalyst, higher HF feed ratios relative to CFC-1215xc tend to favor the formation of HCFC-226 da.

In a preferred embodiment of the present invention, in step (a) of the process of the present invention, the halopropene starting material(s) are vaporized, preferably in the presence of HF, and contacted with HF in a pre-reactor, followed by contact with a fluorination catalyst. If the preferred amount of HF is fed to the pre-reactor, no additional HF is required when the effluent from the pre-reactor is contacted with the fluorination catalyst.

For the catalytic fluorination of halopropene starting material(s) and/or product(s) formed therein in the pre-reactor, suitable temperatures are from about 200 ℃ to about 400 ℃, preferably from about 240 ℃ to about 350 ℃. Higher temperatures generally result in reduced catalyst life. Temperatures below about 240 c can result in the formation of a large amount of products having a degree of fluorination below 5 (i.e., underfluorinated products). For gas phase embodiments of the present invention, suitable reactor pressures may range from about 1 to about 30 atmospheres. Reactor pressures of from about 5 atmospheres to about 20 atmospheres can be advantageously employed to assist in separating HCl from other reaction products in step (b) of the process of the present invention.

The fluorination catalyst used in the process of the invention preferably comprises ZnCr₂O₄(Zinc chromium oxide) and crystalline alpha-Cr₂O₃(alpha-chromium oxide) or by treating said composition comprising ZnCr with a fluorinating agent₂O₄(Zinc chromium oxide) and alpha-Cr₂O₃(alpha-chromium oxide) in the presence of a catalyst. The amount of zinc relative to the total amount of chromium and zinc in these compositions is preferably from about 1 atomic% to about 25 atomic%.

It is noteworthy that it contains ZnCr₂O₄(zinc chromite) and crystalline alpha-chromium oxide, wherein ZnCr is₂O₄Comprises from about 10 atomic% to about 67 atomic% of the chromium in the composition and at least about 70 atomic% of the zinc in the composition, and wherein at least about 90 atomic% of the chromium present in the composition as chromium oxide is as ZnCr₂O₄Or crystalline alpha-chromium oxide; also of note is the inclusion of ZnCr by treatment with a fluorinating agent₂O₄And crystalline alpha-chromium oxide. It is also noteworthy that such a composition contains ZnCr₂O₄And crystalline alpha-chromium oxide, wherein the ZnCr is₂O₄Comprising from about 20 atomic% to about 50 atomic% chromium in the composition. It is also noteworthy that such a composition contains ZnCr₂O₄And crystalline alpha-chromium oxide, wherein the ZnCr is₂O₄Contains at least about 90 atomic percent of the zinc in the composition. Also of note are chromium-containing catalyst compositions comprising zinc chromite (zinc chloride) and crystalline alpha-chromium oxide in which greater than 95 atomic percent of the chromium not present as zinc chromite (zinc chloride) is present as crystalline alpha-chromium oxide. It is also noteworthy that it consists essentially of ZnCr₂O₄Such a content consisting of zinc chromite (zinc chromite) and crystalline alpha-chromium oxideA chromium catalyst composition.

These compositions can be prepared, for example, by a co-precipitation method followed by calcination.

In a typical co-precipitation process, an aqueous solution of a zinc salt and a chromium (III) salt is prepared. The relative concentrations of the zinc salt and chromium (III) salt in the aqueous solution are determined by the overall atomic percentage of zinc relative to chromium that is required in the final catalyst. Thus, the concentration of zinc in the aqueous solution is from about 1 mole% to about 25 mole% of the total concentration of zinc and chromium in the solution. The concentration of chromium (III) in the aqueous solution is generally 0.3 to 3 mol/l, preferably 0.75 to 1.5 mol/l. Although different chromium (III) salts may be employed, for the preparation of the aqueous solution chromium (III) nitrate or its hydrated forms, such as [ Cr (NO)₃)₃(H₂O)₉]The most preferred chromium (III) salts.

Although different zinc salts may be used to prepare the aqueous solution, preferred zinc salts for use in preparing the catalyst for use in the process of the invention include zinc (II) nitrate and hydrated forms thereof such as [ Zn (NO)₃)₂(H₂O)₆]。

The aqueous solution of chromium (III) and zinc salts may then be evaporated under vacuum or at elevated temperature to obtain a solid, which is then calcined.

The aqueous solutions of the chromium (III) and zinc salts are preferably treated with a base such as ammonium hydroxide (ammonia) to precipitate the zinc and chromium as hydroxides. Alkali metal containing bases such as sodium or alkali hydroxides or carbonates may be used but are not preferred. The addition of ammonia to the aqueous solution of the chromium (III) and zinc salts is generally carried out gradually over a period of from 1 to 12 hours. The pH of the solution was monitored during the addition of the base. The final pH is generally from 6.0 to 11.0, preferably from about 7.5 to about 9.0, and most preferably from about 8.0 to about 8.7. The precipitation of the mixture of zinc hydroxide and chromium hydroxide is generally carried out at a temperature of from about 15 ℃ to about 60 ℃, preferably from about 20 ℃ to about 40 ℃. After the addition of ammonia, the mixture is typically stirred for up to 24 hours. Precipitated chromium hydroxide and zinc hydroxide as ZnCr₂O₄And precursors of alpha-chromium oxide。

After the precipitation of the mixture of zinc hydroxide and chromium hydroxide is complete, the mixture is dried. This can be done by evaporating the mixture in an open pan or on a hot plate or steam bath or in an oven or furnace at a suitable temperature. Suitable temperatures include temperatures of about 60 ℃ to about 130 ℃ (e.g., about 100 ℃ to about 120 ℃). Alternatively, the drying step may be carried out under vacuum using, for example, a rotary evaporator.

Optionally, the precipitated zinc and chromium hydroxide mixture may be collected and, if desired, washed with deionized water prior to drying. Preferably, the precipitated zinc and chromium hydroxide mixture is not washed prior to the drying step.

After drying the zinc and chromium hydroxide mixture, the nitrate is decomposed by heating the solid at about 250 ℃ to about 350 ℃. The resulting solid is then calcined at a temperature of from about 400 ℃ to about 1000 ℃, preferably from about 400 ℃ to about 900 ℃.

Further information regarding the zinc and chromium compositions used in the present invention is provided in U.S. patent application 60/511,353[ CL2244 US PRV ], filed on 14/10/2003, which is incorporated herein by reference in its entirety (see also the corresponding international application PCT/US 2004/_____).

The calcined zinc chromite (zinc chloride)/α -chromium oxide compositions of the present invention may be pressed into a variety of different shapes such as pellets for use in a packed reactor. It can also be used in powder form.

The calcined composition is typically pretreated with a fluorinating agent prior to use as a catalyst for changing the fluorine content of halogenated carbon compounds. The fluorinating agent is typically HF, although other fluorinating agents such as sulfur tetrafluoride, carbonyl fluoride, and fluorinated carbon compounds such as trichlorofluoromethane, dichlorodifluoromethane, chlorodifluoromethane, trifluoromethane, or 1, 1, 2-trichlorotrifluoroethane may also be used. This pretreatment can be carried out, for example, by: the catalyst is placed in a suitable vessel, which may be the reactor to be used to carry out the process of the invention, and the dried, calcined catalyst is then passed with HF to partially saturate the catalyst with HF. This is conveniently done by passing HF over the catalyst at a temperature of, for example, about 200 ℃ to about 450 ℃ for about 0.1 to about 10 hours. Nevertheless, this pretreatment is not necessary.

Other catalysts suitable for fluorination of step (a) are compositions comprising zinc halide and alpha-chromium oxide and compositions obtained by treating said compositions comprising zinc halide and alpha-chromium oxide with a fluorinating agent. Examples of such catalysts are disclosed in U.S. patent 3,878,257. The amount of zinc relative to the total amount of chromium and zinc in these compositions is preferably from about 0.1 atomic% to about 25 atomic%; more preferably from about 2 atomic% to about 10 atomic%. Of note are compositions wherein the zinc halide is supported on a support comprising alpha-chromium oxide. Preferably, the alpha-chromium oxide is prepared according to U.S. support 5,036,036. The pretreatment with the fluorinating agent can be carried out in the manner described above for the calcined zinc chromite (zinc chloride)/α -chromium oxide composition.

The compound produced in the fluorination process of step (a) comprises CF₃CCl＝CF₂(CFC-1215xc) and CF₃CHClCF₃(HCFC-226da)。

Halopropane by-products having a higher degree of fluorination than HCFC-226da that may be produced in step (a) include CF₃CClFCF₃(CFC-217ba)。

Halopropane by-products having a lower degree of fluorination than HCFC-226da that may be produced in step (a) include CF₃CHClCClF₂(HCFC-225 da). Other halopropane by-products that may be formed include CFC-216aa (CF)₃CCl₂CF₃)。

Halopropene by-products having a lower degree of fluorination than CFC-1215xc that may be produced in step (a) include E-and Z-CF₃CCl ═ CClF (CFC-1214xb) and CF₃CCl＝CCl₂(CFC-1213xa)。

Effluent from step (a) comprising CFC-1215xc and HCFC-226da, and optionally HFThis is usually separated from the following components: low boiling components, mainly comprising HCl and certain over-fluorinated products such as CFC-217ba and azeotropic HF, and under-fluorinated components such as HCFC-225da, C₃Cl₄F₄Isomers and the high boiling component of CFC-1213 xa.

In one embodiment of the invention, the reactor effluent of step (a) is delivered to a distillation column where HCl and any HCl azeotropes are removed from the top of the column and higher boiling components are removed from the bottom of the column. The product recovered from the bottom of the first distillation column is then passed to a second distillation column in which CFC-217ba and some HF are separated at the top of the second distillation column, with the remaining HF and the contained CF₃CHClCF₃、CF₃CCl＝CF₂And the organic product of the high boiling components is withdrawn from the bottom of the column. The product recovered from the bottom of the second distillation column can then be delivered to a third distillation column, where CF₃CHClCF₃、CF₃CCl＝CF₂And HF are separated at the top of the column, and then the remaining HF and under-fluorinated components are removed from the bottom of the column.

CF recovered from the third distillation column₃CHClCF₃、CF₃CCl＝CF₂And HF are delivered to step (b) or may optionally be delivered to a decanter maintained at a suitable temperature to separate an organic-rich liquid phase from an HF-rich liquid phase. The HF-rich phase may be distilled to recover HF before recycling the HF back to step (a). The organic-rich phase may then be delivered to step (b) or distilled to give pure HCFC-226da and CFC-1215 xc.

In one embodiment of the invention, the under-fluorinated component is, for example, HCFC-225da, C₃Cl₂F₄And CF₃CCl＝CCl₂(CFC-1213xa) may be returned to step (a).

In step (b) of the process of the present invention, the CF formed in step (a) is₃CHClCF₃And CF₃CCl＝CF₂With hydrogen (H)₂) Optionally in the presence of HF.

In one embodiment of step (b), the composition will comprise CF₃CHClCF₃And CF₃CCl＝CF₂With hydrogen (H) in the gas phase, and optionally HF₂) Delivered together into a reactor fabricated from nickel, iron, titanium, or alloys thereof as described in U.S. patent 6,540,933; the teachings of this publication are incorporated herein by reference. Reaction vessels of these materials, optionally filled with metal, in suitable form (e.g. metal tubes) may also be used. When referring to alloys, this refers to nickel alloys containing 1 to 99.9% by weight nickel, iron alloys containing 0.2 to 99.8% by weight iron, and titanium alloys containing 72 to 99.8% by weight titanium. Notably, an empty (i.e. unfilled) reaction vessel made of nickel or a nickel alloy, for example a nickel alloy containing 40-80% nickel, such as Inconel, is used^TM600 nickel alloy, Hastelloy^TMC617 nickel alloy or Hastelloy^TMC276 nickel alloy.

When used for packing, the metal or metal alloy may be in the form of particles or formed shapes such as perforated plates, rings, wires, screens, chips, tubes, beads, tissues or fluff.

In this embodiment, the temperature of the reaction may be from about 350 ℃ to about 600 ℃, preferably at least about 450 ℃.

The molar ratio of hydrogen to the CFC-1215xc/HCFC-226da mixture fed to the reaction zone should be about 0.1 mole H₂Per mole of CFC-1215xc/HCFC-226da mixture to about 60 moles of H₂Per mole of CFC-1215xc/HCFC-226da mixture, more preferably from about 0.4 to about 10 moles of H₂Per mole of CFC-1215xc/HCFC-226da mixture.

In another embodiment of the process of the present invention, the contacting of hydrogen with the CFC-1215xc/HCFC-226da mixture produced in step (a), and optionally HF, is carried out in the presence of a hydrogenation catalyst. Hydrogenation catalysts suitable for use in this embodiment include catalysts comprising at least one metal selected from the group consisting of: rhenium, iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium, and platinum. The catalytic metal component is typically supported on a support such as carbon or graphite or a metal oxide, fluorinated metal oxide or metal fluoride wherein the support metal is selected from magnesium, aluminium, titanium, vanadium, chromium, iron and lanthanum.

Of note are carbon-supported catalysts in which the carbon support has been washed with acid and has an ash content of less than about 0.1% by weight. Hydrogenation catalysts supported on low ash carbon are described in U.S. patent No. 5,136,113, the teachings of which are incorporated herein by reference. It is also noteworthy that it comprises a support of alumina (Al)₂O₃) Fluorinated alumina or aluminum fluoride (AlF)₃) At least one metal selected from the group consisting of palladium, platinum and rhodium.

Supported metal catalysts can be prepared by conventional methods known in the art, for example by impregnating the support with a soluble salt of the catalytic metal (e.g., palladium chloride or rhodium nitrate), as described by Satterfield on page 95 of Heterogenous Catalysis in Industrial Practice, 2 nd edition (McGraw-Hill, New York, 1991). The concentration of catalytic metal on the support is typically from about 0.1 wt% to about 5 wt% of the catalyst.

When a hydrogenation catalyst is used, the relative amounts of hydrogen contacted with CFC-1215xc and HCFC-226da are typically about hydrogen to CF₃CHClCF₃/CF₃CCl＝CF₂Stoichiometric ratio of mixture to about 10 moles of H₂Per mole CF₃CHClCF₃/CF₃CCl＝CF₂And (3) mixing. Hydrogen and CF₃CHClCF₃/CF₃CCl＝CF₂The stoichiometric ratio of the mixture depends on the relative amounts of the two components in the mixture. Conversion of HCFC-226da and CFC-1215xc to CF₃CH₂CF₃And CF₃CH₂CHF₂Required H₂The stoichiometric amounts of (a) and (b) are 1 and 2 moles, respectively.

For catalytic hydrogenation, suitable temperatures are generally from about 100 ℃ to about 350 ℃, preferably from about 125 ℃ to about 300 ℃. Temperatures above about 350 ℃ tend to result in defluorination side reactions; temperatures below about 125 c will result in incomplete H to Cl substitution in the starting material. The reaction is usually carried out under normal pressure or superatmospheric pressure.

The effluent from the reaction zone of step (b) typically comprises HCl, CF₃CH₂CF₃(HFC-236fa)、CF₃CH₂CHF₂(HFC-245fa) and minor amounts of low boiling by-products (typically including propane, CF)₃CH＝CF₂(HFC-1225zc), E-and Z-CF₃CHF (HFC-1234ze) and/or CF₃CH₂CH₃(HFC-263fb)) and high boiling by-products and intermediates, typically including CF₃CHFCH₃(HFC-254eb) and/or CF₃CHClCHF₂(HCFC-235da)) as well as any unconverted feedstock and any HF carried over from step (a).

In step (c), the desired product is recovered. The reactor product of step (b) may be delivered to a separation unit for recovery of CF₃CH₂CF₃And CF₃CH₂CHF₂They are recovered individually, as a mixture or as their HF azeotropes.

Partially chlorinated components such as HCFC-235da may be recovered and returned to step (b).

The reactor, distillation column and its associated feed lines, effluent lines and associated equipment used to carry out the process of the present invention should be constructed of materials resistant to hydrogen fluoride and hydrogen chloride. Typical materials of construction well known in the fluorination art include stainless steels, particularly austenitic stainless steels, well known high nickel alloys such as Monel^TMNickel-copper alloy, Hastelloy^TMNickel-based alloy and Inconel^TMNickel-chromium alloys, and copper-lined steels.

The following specific embodiments are illustrative only and do not limit the remainder of the disclosure in any way.

Examples

Description of the symbols

215aa is CF₃CCl₂CClF₂216aa is CF₃CCl₂CF₃

217ba is CF₃CClFCF₃225da is CF₃CHClCClF₂

226da is CF₃CHClCF₃1213xa is CF₃CCl＝CCl₂

1214 is C₃Cl₂F₄1215xc is CF₃CCl＝CF₂

Preparation of the catalyst

Comparative preparation example 1

Preparation of 100% chromium catalyst (400 ℃ C.)

To 400g Cr (NO)₃)₃[9(H₂O)](1.0 moles) to a solution in 1000mL of deionized water 477mL of 7.4M aqueous ammonia was added dropwise, causing the pH to rise to about 8.5. The slurry was stirred at room temperature overnight. After adjusting the pH to 8.5 again with ammonia, the mixture was poured into an evaporation dish and dried in air at 120 ℃. The dried solid was then calcined in air at 400 ℃; the resulting solid weighed 61.15 g. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 28.2g (20mL) was used in comparative example 1.

Comparative preparation example 2

Preparation of 2% Zinc on alumina catalyst

Alumina (4.90 mol, Harshaw 3945, dried at 110 ℃) was added to 20.85g ZnCl₂(0.153 mol) was dissolved in 460mL of distilled water. Water was evaporated from the mixture under stirring and then dried at 110 ℃ for 3 days. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 21.1g (30mL) was used in comparative example3。

Preparation of example 1

Preparation of 2% Zinc chloride Supported on chromium oxide

A solution of 1.20g ZnCl2(8.81mmol) in 60mL deionized water in a 125mm 65mm glass dish was treated with 60.00g (0.357 mol) of 12-20 mesh Cr₂O₃And (6) processing. The dish was placed on a warm plate and the slurry was allowed to dry with occasional stirring. The resulting solid was then dried at 130 ℃ overnight; the resulting solid weighed 60.42 g. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 41.5g (30mL) was used in example 1.

Preparation of example 2

Preparation of 95% chromium/5% Zinc catalyst (450 ℃ C.)

Preparation of 380.14g Cr (NO)₃)₃[9(H₂O)](0.950 mol) and 14.87gZn (NO)₃)₂[6(H₂O)](0.050 moles) in 1000mL of deionized water. 450mL of 7.4M aqueous ammonium hydroxide was added to the solution over 1 hour; the pH increased from 1.7 to pH 8.4. The slurry was stirred at room temperature overnight and then dried in an oven at 120 ℃ in the presence of air. The dried solid was then calcined in air at 450 ℃ for 20 hours; the resulting solid weighed 76.72 g. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 38.5g (25mL) was used in example 6.

Preparation of example 3

Preparation of 90% chromium/10% Zinc catalyst (900 deg.C)

Preparation of 360.13g Cr (NO)₃)₃[9(H₂O)](0.900 mol) and 29.75gZn (NO)₃)₂[6(H₂O)](0.100 moles) in 1000mL of deionized water. 450mL of 7.4M aqueous ammonium hydroxide was added to the solution over 1.4 hours; the pH increased from 1.9 to pH 8.4. The slurry was stirred at room temperature overnight and then dried at 120 ℃ in the presence of airAnd (5) drying. The dried solid was then calcined in air at 900 ℃ for 20 hours; the resulting solid weighed 75.42 g. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 42.3g (25mL) was used in example 8.

Preparation of example 4

Preparation of 95% chromium/5% Zinc catalyst (900 ℃ C.)

Preparation of 380.14g Cr (NO)₃)₃[9(H₂O)](0.950 mol) and 14.87gZn (NO)₃)₂[6(H₂O)](0.050 moles) in 1000mL of deionized water. 450mL of 7.4M aqueous ammonium hydroxide was added to the solution over 1 hour; the pH increased from 1.7 to pH 8.4. The slurry was stirred at room temperature overnight and then dried in an oven in the presence of air at 120 ℃. The dried solid was then calcined in air at 900 ℃ for 20 hours; the resulting solid weighed 70.06 g. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 25.3g (14mL) was used in example 7.

Preparation of example 5

Preparation of 98% chromium/2% Zinc catalyst (900 ℃ C.)

Preparation of 392.15g Cr (NO)₃)₃[9(H₂O)](0.980 moles) and 5.94gZn (NO)₃)₂[6(H₂O)](0.020 moles) in 1000mL of deionized water. 450mL of 7.4M aqueous ammonium hydroxide was added to the solution over 0.58 hours; the pH increased from 1.67 to pH 8.35. The slurry was stirred at room temperature overnight and then dried in an oven in the presence of air at 120 ℃. The dried solid was then calcined in air at 900 ℃ for 21 hours; the resulting solid weighed 66.00 g. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 44.9g (23mL) was used in example 5.

Preparation of example 6

Preparation of 10% Zinc chloride Supported on chromium oxide

Will be in a 170mm by 90mm glass dishInner 6.0g ZnCl₂(44mmol) in 300mL deionized water with 60.00g (0.357 mol) of 12-20 mesh Cr₂O₃And (6) processing. The dish was placed on a warm plate and the slurry was allowed to dry with occasional stirring. The resulting solid was then dried at 130 ℃ overnight; the resulting solid weighed 65.02 g. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 37.5g (25mL) was used in example 2.

Preparation of example 7

Preparation of 98.1% chromium/1.9% Zinc catalyst (550 deg.C)

516.46g Cr (NO) were prepared in a 1L beaker placed on a hot plate₃)₃[9(H₂O)](1.29 mol) and 7.31g Zn (NO)₃)₂[6(H₂O)](0.0246 mol) in 500mL of distilled water. The mixture was then transferred to Pyrex^TMIn the container, the container is placed in an oven. The vessel was heated from room temperature to 125 ℃ at a rate of 10 ℃/min and then held at 125 ℃ for 6 hours. The vessel was heated from 125 ℃ to 350 ℃ at a rate of 1 ℃/min and then held at 350 ℃ for 6 hours. The vessel was heated from 350 ℃ to 550 ℃ at a rate of 1 ℃/min and then held at 550 ℃ for 24 hours. The catalyst was pelletized (-12 to +20 mesh, (1.68 to 0.84mm)), and 29.9g (20mL) was used in examples 3 and 4.

Examples 1 to 8 and comparative examples 1 to 3

General method of fluorination

Weigh a quantity of catalyst particles and place them in an lnconel 5/8' (1.58cm) diameter^TMIn the nickel alloy reactor tube, the reaction was heated in a fluid sand bath. The reactor tube was placed under a nitrogen stream (50 cc/min; 8.3(10)^-7m³Second) heated from 50 ℃ to 175 ℃ over about 1 hour, then charged to the reactor at 50 cc/min (8.3(10)^-7m³Per second) was introduced into the reactor. After 0.5-2 hours, the nitrogen flow rate was reduced to 20 cc/min (3.3(10)^-7m³Per second), adding HF flow rate reduced to 80 cc/min (1.3(10)^-6m³Second); the flow rate was maintained for about 1 hour. The reactor temperature was then gradually increased to 400 ℃ over 3-5 hours. At the end of this period, the HF flow was stopped at 20sccm (3.3(10)^-7m³Per second) the reactor was cooled to 300 ℃ under a nitrogen flow. CFC-1213xa was fed from a pump to a vaporizer maintained at about 118 ℃. CFC-1213xa vapor was packed with a suitable molar ratio of HF in a 0.5 inch (1.27cm) diameter pack with Monel^TMSliced Monel^TMThe nickel alloy tubes were combined. Then allowing the mixture of reactants to enter a reactor; unless otherwise stated, the contact time was 15 seconds. All reactions were carried out at a nominal pressure of 1 atmosphere. The results of CFC-1213xa fluorination using several catalysts are shown in Table 1. Analytical data are given in units of GC area%.

Claims (7)

1. Mixing HF with at least one of formula CX₃Halogenated propenes as shown by CCl ═ CClX to produce halogenated propenes containing CF₃CCl＝CF₂And CF₃CHClCF₃Wherein each X is independently selected from F and Cl, and wherein the CF₃CCl＝CF₂And CF₃CHClCF₃Is formed in the presence of a fluorination catalyst comprising at least one composition selected from the group consisting of: (i) containing ZnCr₂O₄And crystalline alpha-chromium oxide; (ii) a composition comprising a zinc halide and alpha-chromium oxide;and (iii) a composition of (i) or (ii) that has been treated with a fluorinating agent.

2. The process of claim 1 wherein the fluorination catalyst is selected from the group consisting of (i) comprises ZnCr₂O₄And (iii) a composition of (i) that has been treated with a fluorinating agent.

3. The process of claim 2 wherein the amount of zinc relative to the total amount of chromium and zinc in the catalyst composition is from about 1 atomic% to about 25 atomic%.

4. The process of claim 2, wherein the catalyst is selected from the group consisting of (i) catalysts comprising ZnCr₂O₄And crystalline alpha-chromium oxide, in which ZnCr is present₂O₄Comprises from about 10 atomic% to about 67 atomic% of the chromium in the composition and at least about 70 atomic% of the zinc in the composition, and wherein at least about 90 atomic% of the chromium present in the composition as chromium oxide is as ZnCr₂O₄Or crystalline alpha-chromium oxide; and (iii) the composition of (i) which has been treated with a fluorinating agent.

5. The process of claim 1, wherein the fluorination catalyst is selected from the group consisting of (ii) compositions comprising zinc halide and alpha-chromium oxide, and (iii) compositions of (ii) that have been treated with a fluorinating agent.

6. The process of claim 5 wherein the amount of zinc relative to the total amount of chromium and zinc in the catalyst composition is from about 0.1 atomic% to about 25 atomic%.

7. The process of claim 5, wherein the catalyst is selected from the group consisting of (ii) a composition in which a zinc halide is supported on a support comprising alpha-chromium oxide, and (iii) a composition of (ii) that has been treated with a fluorinating agent; and wherein the amount of zinc relative to the total amount of chromium and zinc in the catalyst composition is from about 2 atomic% to about 10 atomic%.