Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C17/00—Preparation of halogenated hydrocarbons
  • C07C17/25—Preparation of halogenated hydrocarbons by splitting-off hydrogen halides from halogenated hydrocarbons
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C17/00—Preparation of halogenated hydrocarbons
  • C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
  • C07C17/20—Preparation of halogenated hydrocarbons by replacement by halogens of halogen atoms by other halogen atoms
  • C07C17/202—Preparation of halogenated hydrocarbons by replacement by halogens of halogen atoms by other halogen atoms two or more compounds being involved in the reaction
  • C07C17/206—Preparation of halogenated hydrocarbons by replacement by halogens of halogen atoms by other halogen atoms two or more compounds being involved in the reaction the other compound being HX
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C21/00—Acyclic unsaturated compounds containing halogen atoms
  • C07C21/02—Acyclic unsaturated compounds containing halogen atoms containing carbon-to-carbon double bonds
  • C07C21/18—Acyclic unsaturated compounds containing halogen atoms containing carbon-to-carbon double bonds containing fluorine

Definitions

• the present invention relates to a process for the production of fluorinated compounds, such as hydrofluoroolefins or hydrofluorocarbons for example, and an installation adapted to the implementation of this process.
• hydrofluoroolefins or hydrofluorocarbons by fluorination of hydrochloro-olefins or hydrochlorocarbons in particular.
• This fluorination is generally a catalytic fluorination using hydrofluoric acid as fluorinating agent.
• the fluorination reaction should generally be carried out at a high temperature (over 300 ° C) in the gas phase. Therefore, it is known to heat, vaporize and overheat the reactants before the fluorination reaction, using heat exchangers.
• WO 2014/120865 discloses a process for reducing the decomposition of chlorinated compounds.
• WO 2015/055927 discloses a process for producing fluorinated compounds from chlorinated compounds, the latter being vaporized.
• No. 6,034,288 also discloses a process for the vaporization of halocarbons.
• the invention relates to a process for producing a fluorinated compound comprising the steps of:
• step c) vaporizing said droplets produced in step c) by mixing with said gas stream, the resulting mixture being a gaseous mixture; e) the catalytic reaction of the chlorinated compound with hydrofluoric acid in the gas phase and the collection of a product stream;
• step c) characterized in that the droplets produced in step c) have an average diameter of less than 500 ⁇ .
• the droplets produced have a mean diameter of less than 150 ⁇ , preferably less than 100 ⁇ .
• more than 90% of the droplets produced have a mean diameter of less than 500 ⁇ .
• the chlorinated compound is a chlorocarbon, a hydrochlorocarbon, a chlorofluorocarbon, a hydrochlorofluorocarbon, a chloroolefin, a hydrochloroolefin, a chlorofluoroolefin or a hydrochlorofluoroolefin; and wherein the fluorinated compound is a fluorocarbon, a hydrofluorocarbon, a chlorofluorocarbon, a hydrochlorofluorocarbon, a fluoroolefin, a hydrofluoroolefin, a chlorofluoroolefin or a hydrochlorofluoroolefin; preferably, the chlorinated compound is chosen from 1,1,2-trichloroethane, 1,1,1,2,3-pentachloropropane, 1,1,1,3,3-pentachloropropane, 1,1,2- 2,3-pentachloropropane, 2,3-
• steps c) and d) are implemented in a spraying, spraying and mixing unit, the latter being a static mixer comprising one or more spray nozzles equipped with orifices capable of allow the formation of droplets of average diameter less than 500 ⁇ .
• the method also comprises one or more steps of separation of the product stream, making it possible to collect, on the one hand, a stream of the fluorinated compound and, on the other hand, a recycling stream; preferably the recycle stream provides the gas stream comprising hydrofluoric acid, optionally after a supply of hydrofluoric acid or preferably a catalytic fluorination step of the recycle stream is carried out, where appropriate with a supply of hydrofluoric acid, the gas stream comprising of hydrofluoric acid being collected at the end of this fluorination step.
• the method also comprises a step of heating the liquid stream of chlorinated compound at a temperature below the vaporization temperature thereof.
• the method comprises, after step d), and before step e):
• the invention relates to a plant for producing a fluorinated compound comprising:
• a feed line for liquid flow of chlorinated compound A gas flow feed line comprising hydrofluoric acid;
• a spraying, vaporization and mixing unit fed by the chlorinated compound liquid feed line and the gas flow supply line comprising hydrofluoric acid;
• a product flow collection line at the outlet of the catalytic fluorination reactor A product flow collection line at the outlet of the catalytic fluorination reactor
• the spraying, vaporizing and mixing unit is a static mixer comprising one or more spray nozzles equipped with orifices adapted to allow the formation of droplets with an average diameter of less than 500 ⁇ .
• the chlorinated compound is a chlorocarbon, a hydrochlorocarbon, a chlorofluorocarbon, a hydrochlorofluorocarbon, a chloroolefin, a hydrochloroolefin or a hydrochlorofluoroolefin; and wherein the fluorinated compound is a fluorocarbon, a hydrofluorocarbon, a chlorofluorocarbon, a hydrochlorofluorocarbon, a fluoroolefin, a hydrofluoroolefin or a hydrochlorofluoroolefin; preferably, the chlorinated compound is chosen from 1,1,2-trichloroethane, 1,1,1,2,3-pentachloropropane, 1,1,1,3,3-pentachloropropane, 1,1,2- 2,3-pentachloropropane, 2,3-dichloro-1,1,1-trifluoropropane, perchlorethylene, 1,2-
• the installation comprises at least one separation unit fed by the product flow collection pipe; and a fluorinated compound collection pipe and a recycle stream collection pipe at the outlet of the separation unit or units.
• the recycle flow collection line and optionally a hydrofluoric acid supply line feed the gas flow supply line comprising hydrofluoric acid.
• the installation comprises a catalytic fluorination reactor fed at least in part by the recycle flow collection line, where appropriate with a supply of hydrofluoric acid, the gas flow supply line. comprising hydrofluoric acid originating from the catalytic fluorination reactor.
• the installation comprises heating means on the chlorinated compound liquid feed line. Said heating means make it possible to heat the liquid stream of chlorinated compound, without vaporizing it, the latter remaining in liquid form.
• the installation comprises heating means or cooling means on the gas mixture collection pipe.
• the present invention overcomes the disadvantages of the state of the art. It provides more particularly a process for producing fluorinated compounds limiting or avoiding the problem of coking the installation. This is accomplished by specifically spraying the main reagent (chlorinated compound to be fluorinated) to form droplets of a specific average diameter and then vaporizing the formed droplets by mixing it with a gaseous hot stream that contains hydrofluoric acid. . By specifically limiting the size of the droplets, problems of incomplete or late vaporization of the chlorinated compound are avoided, two factors favoring coking.
• the main reagent chlorinated compound to be fluorinated
• Figure 1 shows the spray angle ⁇ of a nozzle for spraying the liquid stream into droplets.
• FIG. 2 schematically shows an embodiment of the installation according to the invention.
• FIG. 3 schematically shows another embodiment of the installation according to the invention.
• a process for producing a fluorinated compound comprises the steps of:
• step d) vaporizing said droplets produced in step c) by mixing with said gas stream, the resulting mixture being a gaseous mixture;
• the droplets produced in step c) have an average diameter of less than 500 ⁇ .
• the droplets produced in step c) have a mean diameter of less than 450 ⁇ , preferably less than 400 ⁇ , more preferably less than 350 ⁇ , in particular less than 300 ⁇ , more particularly less than 250 ⁇ , so less than 200 ⁇ , advantageously less than 150 ⁇ , of preferentially preferred way less than 100 ⁇ , particularly preferably less than 75 ⁇ .
• more than 50% of the droplets produced have a mean diameter of less than 500 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 500 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 500 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 500 ⁇ , in particular more than 70% of the droplets produced in step c) have an average diameter of less than 500 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 500 ⁇ , preferably more than 80% of the droplets produced in step c) have an average diameter of less than 500 ⁇ , advantageously more preferably 85% of the droplets produced in step c) have an average diameter of less than 500 ⁇ , preferentially preferred more than 90% of the droplets produced in step c) have a mean diameter of less than 500 ⁇ , particularly preferably more than 95% of the
• more than 50% of the droplets produced have a mean diameter of less than 450 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 450 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 450 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 450 ⁇ , in particular more than 70% of the droplets produced in step c) have an average diameter of less than 450 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 450 ⁇ , preferably more than 80% of the droplets produced in step c) have an average diameter of less than 450 ⁇ , advantageously more preferably 85% of the droplets produced in step c) have an average diameter of less than 450 ⁇ , preferentially preferred more than 90% of the droplets produced in step c) have a mean diameter of less than 450 ⁇ ,
• more than 50% of the droplets produced have a mean diameter of less than 400 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 400 ⁇ , preferably more than 60%.
• droplets produced in step c) have an average diameter of less than 400 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 400 ⁇ , in particular more than 70% of the droplets.
• produced in step c) have a mean diameter of less than 400 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 400 ⁇ , preferably more than 80% of the droplets produced.
• step c) have a mean diameter of less than 400 ⁇ , advantageously more than 85% of the droplets produced in step c) have an average diameter of less than 400 ⁇ , preferably more than 90% of the droplets produced in step c) have an average diameter of less than 400 ⁇ , particularly preferably more than 95% of the droplets produced in step c) have an average diameter of less than 400 ⁇ .
• more than 50% of the droplets produced have an average diameter of less than 350 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 350 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 350 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 350 ⁇ , in particular more than 70% of the droplets produced in step c) have an average diameter of less than 350 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 350 ⁇ , preferably more than 80% of the droplets produced in step c) have an average diameter of less than 350 ⁇ , advantageously more preferably 85% of the droplets produced in step c) have an average diameter of less than 350 ⁇ , preferably more than 90% of the droplets produced in step c) have a mean diameter of less than 350 ⁇ , particularly preferably more than 95% of the droplets produced
• more than 50% of the droplets produced have a mean diameter of less than 300 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 300 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 300 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 300 ⁇ , in particular more than 70% of the droplets produced in step c) have an average diameter of less than 300 ⁇ , more particularly more than 75% of the droplets produced in step c) have a mean diameter of less than 300 ⁇ , more preferably 80% of the droplets produced in step c) have an average diameter of less than 300 ⁇ , advantageously more than 85% of the droplets produced in step c) have an average diameter of less than 300 ⁇ , preferentially preferred more than 90% of the droplets produced in step c) have a mean diameter of less than 300 ⁇ , particularly preferably more than 95% of the drop
• more than 50% of the droplets produced have a mean diameter of less than 250 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 250 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 250 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 250 ⁇ , in particular more than 70% of the droplets produced in step c) have an average diameter of less than 250 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 250 ⁇ , preferably more than 80% of the droplets produced in step c) have an average diameter of less than 250 ⁇ , advantageously more preferably 85% of the droplets produced in step c) have an average diameter of less than 250 ⁇ , preferably more than 90% of the droplets produced in step c) have a mean diameter of less than 250 ⁇ , particularly preferably more than 95% of the droplets
• more than 50% of the droplets produced have a mean diameter of less than 200 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 200 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 200 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 200 ⁇ , in particular more than 70% of the droplets produced in step c) have an average diameter of less than 200 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 200 ⁇ , preferably more than 80% of the droplets produced in step c) have an average diameter of less than 200 ⁇ , advantageously more preferably 85% of the droplets produced in step c) have an average diameter of less than 200 ⁇ , preferably more than 90% of the droplets produced in step c) have an average diameter of less than 200 ⁇ , so Particularly preferred more than 95% of the droplets
• more than 50% of the droplets produced have a mean diameter of less than 150 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 150 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 150 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 150 ⁇ , in particular more than 70% of the droplets produced in step c) have an average diameter of less than 150 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 150 ⁇ , preferably more than 80% of the droplets produced in step c) have an average diameter of less than 150 ⁇ , advantageously more preferably 85% of the droplets produced in step c) have an average diameter of less than 150 ⁇ , preferably more than 90% of the droplets produced in step c) have a mean diameter of less than 150 ⁇ , particularly preferably more than 95% of the droplets
• more than 50% of the droplets produced have a mean diameter of less than 100 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 100 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 100 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 100 ⁇ , in particular more than 70% of the droplets produced in step c) have an average diameter of less than 100 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 100 ⁇ , preferably more than 80% of the droplets produced in step c) have an average diameter of less than 100 ⁇ , advantageously more preferably 85% of the droplets produced in step c) have a mean diameter of less than 100 ⁇ , preferably more than 90% of the droplets produced in step c) have a mean diameter of less than 100 ⁇ , particularly preferably more than 95% of the drop
• more than 50% of the droplets produced have a mean diameter of less than 75 ⁇ .
• more than 55% of the droplets produced in step c) have an average diameter of less than 75 ⁇ , preferably more than 60% of the droplets produced in step c) have an average diameter of less than 75 ⁇ , more preferably more than 65% of the droplets produced in step c) have an average diameter of less than 75 ⁇ , in particular more than 70% of the droplets produced.
• step c) have a mean diameter of less than 75 ⁇ , more particularly more than 75% of the droplets produced in step c) have an average diameter of less than 75 ⁇ , preferably more than 80% of the droplets produced at step c) have an average diameter of less than 75 ⁇ , advantageously more than 85% of the droplets produced in step c) have an average diameter of less than 75 ⁇ , preferably more than 90% of the droplets produced in step c) have an average diameter of less than 75 ⁇ , particularly preferably more than 95% of the droplets produced in step c) have a diameter of average less than 75 ⁇ .
• said droplets produced in step c) are sprayed at a spray angle of from 10 ° to 180 °, preferably from 20 ° to 170 °, in particular from 30 ° to 165 °.
• the spray angle ⁇ corresponds to the angle of the jet emitted by an orifice 32 of a nozzle 31 determined at a distance d of 10 cm from all the orifices 32 of said nozzle 31 considered ( Figure 1).
• the ratio between the volume median diameter (DMV) and the median diameter of the number (DMN) is between 1 and 3, preferably between 1 and 2.5, in particular between 1.2 and 2.
• the median volume is the diameter of the droplet dividing all the others into two groups of equal volume, one consisting of the largest droplets and the other smaller.
• the median diameter of the number is the diameter of the droplet on either side of which is 50% of the total number of droplets. More R is close to 1 and the droplet sizes are similar.
• the nozzle is made of a material resistant to hydrofluoric acid, such as for example 316L stainless steel, alloys of Monel ® , Inconel ® or Hastelloy ® type or nickel-based alloys.
• the partial pressure of the chlorinated compound during its vaporization is relatively moderate, and therefore the vaporization temperature is also relatively moderate, and in any case lower than the vaporization temperature in the room. where the chlorinated compound is vaporized independently.
• the gaseous flow comprising hydrofluoric acid is at a temperature of 100 to 400 ° C., more particularly of 130 to 380 ° C., and advantageously of 250 to 380 ° C. at the time of its mixing with the liquid flow of chlorinated compound.
• the temperature of the gaseous flow comprising hydrofluoric acid, at the time of its mixing with the liquid flow of chlorinated compound is chosen:
• the temperature of the gaseous stream comprising hydrofluoric acid may be about 320 to 380 ° C.
• the invention relates to the fluorination of a chlorinated compound with hydrofluoric acid to form a fluorinated compound.
• chloro compound an organic compound comprising one or more chlorine atoms
• fluorine compound means an organic compound comprising one or more fluorine atoms
• the chlorinated compound may comprise one or more fluorine atoms, and that the fluorinated compound may comprise one or more chlorine atoms.
• the number of chlorine atoms of the fluorinated compound is less than the number of chlorine atoms of the chlorinated compound; and the number of fluorine atoms of the fluorinated compound is greater than the number of fluorine atoms of the chlorinated compound.
• the chlorinated compound may be an alkane or an alkene optionally having substituents selected from F, Cl, I and Br (preferably from F and Cl), and having at least one substituent Cl.
• the fluoro compound may be an alkane or an alkene optionally having substituents selected from F, Cl, I and Br (preferably from F and Cl), and having at least one substituent F.
• the chlorinated compound may especially be an alkane with one or more substituents chlorine (hydrochlorocarbon or chlorocarbon) or an alkane with one or more substituents chlorine and fluorine (hydrochlorofluorocarbon or chlorofluorocarbon) or an alkene with one or more substituents chlorine (chloroolefin or hydrochlorohefin) or an alkene with one or more substituents chlorine and fluorine (hydrochlorofluoroolefin or chlorofluoroolefin).
• the fluorinated compound may in particular be an alkane with one or more fluorine substitutions (fluorocarbon or hydrofluorocarbon) or an alkane with one or more substituents chlorine and fluorine (hydrochlorofluorocarbon or chlorofluorocarbon) or an alkene with one or more fluorine substituents (fluoroolefin or hydrofluoroolefin) or an alkene with one or more substituents chlorine and fluorine (hydrochlorofluoroolefin or chlorofluoroolefin).
• the chlorinated compound and the fluorinated compound may be linear or branched, preferably linear.
• the chlorinated compound and the fluorinated compound comprise a single carbon atom.
• the chlorinated compound and the fluorinated compound comprise two carbon atoms.
• the chlorinated compound and the fluorinated compound comprise three carbon atoms.
• the chlorinated compound and the fluorinated compound comprise four carbon atoms.
• the chlorinated compound and the fluorinated compound comprise five carbon atoms.
• the invention is particularly applicable to the following fluorination reactions:
• the conversion of the chlorinated compound to the fluorinated compound may be a direct conversion (with a single reaction step or with a single set of reaction conditions ) or indirect conversion (with two or more reaction steps or using two or more sets of reaction conditions).
• the fluorination reaction can be carried out:
• At an absolute pressure ranging from atmospheric pressure to 20 bara, preferably from 2 to 18 bara, more preferably from 3 to 15 bara;
• a temperature (catalytic bed temperature) of 200 to 450.degree. C., preferably of 250 to 400.degree. C., and more particularly of 280 to 380.degree.
• the fluorination reaction is carried out in the presence of a catalytic composition.
• the catalyst composition comprises a chromium catalyst.
• the chromium catalyst may be a chromium oxide (eg CrO 2, CrO 3 or CT 2 O 3), a chromium oxyfluoride or a chromium fluoride (eg CrF 5) or a mixture thereof.
• the chromium oxyfluoride may contain a fluorine content of between 1 and 60% by weight based on the total weight of the chromium oxyfluoride, advantageously between 5 and 55% by weight, preferably between 10 and 52% by weight, more preferably between 15 and 52% by weight, in particular between 20 and 50% by weight, more particularly between 25 and 45% by weight, preferably between 30 and 45% by weight, more preferably from 35 to 45% by weight. by weight of fluorine based on the total weight of the chromium oxyfluoride.
• the catalyst composition may also comprise a co-catalyst selected from the group consisting of Ni, Co, Zn, Mg, Mn, Fe, Zn, Ti, V, Zr, Mo, Ge, Sn, Pb, Sb; preferably Ni, Co, Zn, Mg, Mn; in particular Ni, Co, Zn.
• the content by weight of the cocatalyst is between 1 and 10% by weight based on the total weight of the catalytic composition.
• the catalytic composition may also comprise a support such as alumina, for example in its alpha form, activated alumina, aluminum halides (AI F3 for example), aluminum oxyhalides, activated carbon, fluoride magnesium or graphite.
• the catalytic composition has a specific surface area between 1 and 100 m 2 / g, preferably between 5 and 80 m 2 / g, more preferably between 5 and 70 m 2 / g, ideally between 5 and 50 m 2 / g. in particular between 10 and 50 m 2 / g, more particularly between 15 and 45 m 2 / g.
• an oxidation agent for example oxygen or chlorine
• a molar ratio of oxidation agent / organic compounds of 0.005 to 2 preferably from 0.01 to 1.5.
• oxygen or chlorine oxygen or chlorine
• the catalyst composition is preferably activated with air, oxygen or chlorine and / or with HF.
• the catalytic composition Prior to its use, the catalytic composition is preferably subjected to activation with air or oxygen and HF at a temperature of 100 to 500 ° C, preferably 250 to 500 ° C and more preferably 300 to 500 ° C. at 400 ° C.
• the activation time is preferably from 1 to 200 hours and more particularly from 1 to 50 hours.
• This activation may be followed by a final fluorination activation step in the presence of an oxidizing agent, HF and organic compounds.
• the molar ratio of HF / organic compounds is preferably from 2 to 40 and the molar ratio of oxidation agent / organic compounds is preferably from 0.04 to 25.
• the temperature of the final activation is preferably from 300 to 400 ° C. C and its duration preferably from 6 to 100 h.
• the plant according to the invention comprises a HCC-240db 2 liquid flow supply line and a gas flow supply line comprising HF 5, which feed a catalytic fluorination reactor 8.
• HCC-240db liquid flow feed 2 is derived from a liquid HCC-240db stock 1.
• the gas flow feed line comprising HF 5 can carry a pure HF stream (possibly in combination with an agent). as described above) or, alternatively, a mixture of HF and organic compounds, especially chlorinated and / or fluorinated organic compounds, as is the case in the example illustrated, and as will be described in more detail below.
• a spraying, spraying and mixing unit 4 is supplied by both the HCC-240db 2 liquid flow supply line and the gas flow supply line comprising HF 5.
• This unit is adapted mixing the gas stream and the liquid stream. It is preferably a static mixer to enable a continuous type process.
• the static mixer comprises one or more spray nozzles equipped with orifices having a specific diameter. Said one or more spray nozzles allow spraying of the liquid stream into the static mixer before it is vaporized.
• said one or more nozzles have orifices capable of allowing the formation of droplets with an average diameter of less than 500 ⁇ .
• said one or more nozzles may have orifices capable of allowing the formation of droplets with an average diameter of less than 450 ⁇ , preferably less than 400 ⁇ , more preferably less than 350 ⁇ , in particular less than 300 ⁇ , more particularly less than 250 ⁇ , preferably less than 200 ⁇ , advantageously privileged less than 150 ⁇ , preferentially preferred less than 100 ⁇ , particularly preferably less than 75 ⁇ .
• the gas stream comprising THF yields heat to the HCC-240db liquid stream, allowing vaporization of the HCC-240db.
• Spray nozzles having the characteristics mentioned in the present application are therefore commercially available.
• the inventors have surprisingly noticed that the use of nozzles specifically allowing the formation of droplets with a mean diameter of less than 500 ⁇ limits the formation of coke in equipment such as heat exchangers, supply lines or the reactor catalytic.
• the mixture of HCC-240db, HF and possibly additional compounds is collected in a gaseous mixture collection line 6 at the outlet of the spraying, spraying and mixing unit 4, which transports the mixture to the reactor.
• HCC-240db may undergo a preliminary heating step prior to mixing with the gas stream comprising HF.
• this preliminary heating is performed at a temperature below the vaporization temperature of HCC-240db (and at a temperature below the degradation or decomposition temperature of this compound).
• a product flow collection line 9 At the outlet of the catalytic fluorination reactor 8 is connected a product flow collection line 9.
• a separation unit 10 or several successive separation units
• This product of interest is recovered in a fluorinated compound collection line 11 at the outlet of the separation unit 10.
• a recycling stream is recovered in a recycling flow collection line 12.
• Other products can be eliminated elsewhere at this stage (in particular the hydrochloric acid generated during the fluorination reaction).
• the recycling stream may contain in particular unreacted reagents, namely HF and chlorinated compound (in this case HCC-240db). It may also contain secondary products resulting from the reaction, that is to say fluorinated products obtained by fluorination of the chlorinated compound (HCC-240db) and other than the desired fluorinated compound.
• the recycling stream contains in particular HCFO-1233xf, and optionally HFC-245cb (1,1,1,2,2-pentafluoropropane), obtained by fluorination of HCC-240db.
• the recycling stream can be directly returned to the catalytic fluorination reactor 8. According to another possible embodiment, it can undergo a completely separate treatment, or even a separate recovery . According to another possible embodiment, it is partially returned to the catalytic fluorination reactor 8.
• the recycle stream undergoes a complementary fluorination before being returned to the main catalytic fluorination reactor 8.
• the recycling stream collection line 12 feeds a complementary catalytic fluorination reactor 16.
• An HF supply line 13 may, as the case may be, as shown, be connected thereto in order to supply fresh THF.
• An oxidizing agent supply line 14 may also, where appropriate, as shown, be connected to a recycle stream collection line 12 to ensure an addition of oxidizing agent capable of maintaining the catalytic activity of the catalyst.
• Heating and vaporization means 15 may be provided on the recycle flow collection line 12 in order to bring the flow to the desired temperature for the complementary fluorination reaction, which is carried out in the complementary catalytic fluorination reactor 16.
• the gaseous feed line comprising THF 5 (previously described) is directly from the complementary catalytic fluorination reactor 16.
• the gas stream comprising THF contains, besides THF (and the case optionally of the oxidizing agent), fluorinated products resulting from the complementary fluorination reaction.
• Fresh HF input and / or an oxidizing agent supply can be added to the gas flow supply line comprising HF 5 if necessary.
• the gas stream comprising HF (which is used to vaporize the liquid flow of chlorinated compound) corresponds to a stream resulting from a fluorination reaction complementary to a recycling stream.
• Other variants are possible:
• the gas stream comprising HF may be a stream resulting from a fluorination reaction complementary to a recycle stream, supplemented with additional HF and / or additional oxidation agent;
• the gas stream comprising HF may be directly a recycle stream or a partial recycle stream (without a complementary fluorination reaction stage);
• the gas stream comprising HF can be directly a recycle stream (without complementary fluorination reaction step), supplemented with additional HF and / or additional oxidizing agent;
• the gas stream comprising HF may be a fresh HF stream optionally comprising fresh oxidizing agent.
• a recycle stream it may be introduced after the step of mixing the gas stream comprising HF with the liquid stream of chlorinated compound; and, if a fluorination reaction complementary to a recycle stream is used, the stream resulting from this reaction can be introduced after the step of mixing the gas stream comprising HF with the liquid stream of chlorinated compound.
• FIG. 3 Another embodiment is now described with reference to FIG. 3: it is a method of producing HFC-125 from PE (as well as the installation allowing its implementation).
• the plant has a gas flow supply line comprising HF 25 and a liquid flow supply line of PER 21, both of which feed a spray, spray and mix unit 22, which is a static mixer.
• the static mixer comprises one or more spray nozzles equipped with orifices having a specific diameter. Said one or more nozzles Spraying allows spraying of the liquid stream into the static mixer before it is vaporized.
• said one or more nozzles have orifices capable of allowing the formation of droplets with an average diameter of less than 500 ⁇ .
• said one or more nozzles may have orifices capable of allowing the formation of droplets with an average diameter of less than 450 ⁇ , preferably less than 400 ⁇ , more preferably less than 350 ⁇ , in particular less than 300 ⁇ , more particularly less than at 250 ⁇ , advantageously less than 200 ⁇ , advantageously privileged less than 150 ⁇ , preferably preferentially less than 100 ⁇ , particularly preferably less than 75 ⁇ .
• a gas mixture collection line 23 which feeds one or a series of several fluorination reactors (not shown).
• Heating means 26a, 26b, 26c are provided on the gas flow supply line comprising HF 25.
• Heating means 24a, 24b are provided on the gas mixture collection pipe 23.
• the gas stream comprising HF is obtained by heating and optionally vaporization of a recycled stream collected after treatment and separation of a product stream from the catalytic fluorination reaction.
• Some of the heating means 26a, 24a employed may be heat-saving exchangers.
• the vaporization of the chlorinated compound and its mixture with hydrofluoric acid is achieved by substantially limiting the coking phenomenon. This makes it possible to maintain the productivity of the process on an industrial scale.
• a gaseous stream 5 coming from a fluorination reactor 8 and comprising HF is mixed with a liquid stream 2 of 240db preheated to a temperature of 120 ° C. at a pressure of 4 to 6 bara.
• the flow rate of the gas stream comprising HF from the fluorination reactor is 20 to 50 kg / h.
• This gas stream is at a temperature of 320 ° C to 350 ° C and a pressure of 3 to 5 bara.
• the flow rate of the 240db liquid flow is 3 to 4 kg / h.
• the mixing between the two flows is carried out in a static mixer 4 which does not comprise spray nozzles (no droplet formation). After 500h, a visual inspection of the supply line at reactor is carried out and the formation of coke is observed.
• the first layers of the catalytic bed in the reactor also have a coke deposit.
• Example 1 is repeated using a static mixer 4 comprising a nozzle whose orifices form droplets with a mean diameter of less than 200 ⁇ . After 500 hours, visual inspection of the reactor feed line and first layers of the catalyst bed showed no coke deposits.
• Example 3 (comparative)
• the installation comprises a gas flow supply line comprising HF 25 and a liquid flow feed line of perchlorethylene 21, both of which supply a static mixer. 22.
• the static mixer 22 comprises a nozzle whose orifices form droplets with an average diameter greater than 700 ⁇ . A visual inspection is performed after 1000 hours. Coke formation at the nozzle and in the static mixer is observed.
• Example 3 is repeated with a static mixer 22 comprising a nozzle whose orifices form droplets with a mean diameter of less than 200 ⁇ .
• a visual inspection is carried out after 8000 h. Inspection of the nozzle and the associated static mixer does not indicate fouling by coking.

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• 2017
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