PROPENES

FIELD

[00011 The present invention relates to processes for the production of chlorinated propanes and/or propenes,

BACKGROUND

[0002] Hydrofluorocarbon (HFC) products are widely utilized in many applications, including refrigeration, air conditioning, foam expansion, and as propellants for aerosol products including medical aerosol devices. Although HFC's have proven to be more climate friendly than the ch!orofluoroearbon and hydrochlorofluorocarbon products that they replaced, it has now been discovered that they exhibit an appreciable global warming potential (GWP).

[00031 The search for more acceptable alternatives to current fiuorocarbon products has fed to the emergence of hydrofluoroolefin (HFO) products. Relative to their predecessors, HFOs are expected to exert less impact on the atmosphere in the form of a lesser, or no, detrimental impact on the ozone layer and their much lower GWP as compared to HFC's. Advantageously, HFO's also exhibit low flammability and low toxicity.

[0004] As the environmental, and thus, economic importance of HFO's has developed, so has the demand for precursors utilized in their production. Many desirable HFO compounds, e.g., such as 2,3,3,3 -tetrafiuoroprop-l-ene, may typically be produced utilizing feedstocks of chlorocarbons, and in particular, chlorinated propenes, which may also find use as feedstocks for the manufacture of polyurethane blowing agents, biocides and polymers.

[0005] Unfortunately, many chlorinated propanes and/or propenes may have limited commercial availability, and/or may only be available at prohibitively high cost. This may be due at least in part to the fact that conventional processes for their manufacture may require the use of starting materials that are prohibitively expensive, or otherwise too limited in the throughputs that can be achieved, to be economically produced by manufacturers on the large scale required to be useful as feedstocks. And, conventional starting materials may typically desirably be used in processes and/or reactors in a way such that conversion thereof is limited, as conversion, e.g., of 90% or greater, of conventional starting materials can result in a lack of selectivity and formation of large amounts of unwanted or unusable secondary products into the process. And, heat removal to the degree required from many conventional reactors would be cost prohibitive if incorporated into a large scale process, due to the highly exothermic nature of many chiorination reactions.

[0006] It would thus be desirable to provide improved processes for the production of chlorocarbon precursors useful as feedstocks in the synthesis of refrigerants and other commercial products. More particularly, such processes would provide an improvement over the current state of the art if they were less costly not only in starting materials and/or operational costs of running the processes, but also, provided a greater selectivity to final products.

BRIEF DESCRIPTION

[0007] The present invention provides efficient processes for the production of chlorinated propanes and/or propenes. Advantageously, the processes make use of methylacetylene gas, a by-product in the production of ethylene and propylene, as a low cost starting material. In some embodiments, the feed stream may comprise a combination of methylacetylene and one or more of propadiene, propene, or propane, thereby avoiding a. purification step to separate the methylacetylene from a typical product stream comprising the same prior to use in the process. In fact, in some embodiments wherein the methylacetylene feed stream comprises MAPP gas, the process itself may provide a substantially pure stream of propane as a further product in addition to the chlorinated propanes and/or propenes. Advantageously, methylacetylene, propene and propadiene are readily chlorinated across their double and/or triple bonds, and so, fewer successive dehydrochlorination and chiorination steps may be required as compared to conventional processes that start with less unsaturated or less chlorinated raw materials, such as, e.g., di- or trichloropropane. In some embodiments, caustic cracking is only required for the last conversion of pentachloropropane isomers to 1 , 1,2,3-tetrachIoropropene and its desirable isomer(s), and anhydrous HC1 can be recovered from the process rather than the lower value NaCi produced by multipie caustic cracking steps. Less waste water is thus generated, providing further time and cost savings.

[0008] In one aspect, the present invention provides a process for the production of chlorinated propanes and/or propenes from a feed stream comprising methylacetylene. The feed stream may further comprise one or more of propadiene, propene and/or propane. In some embodiments, the feed stream may comprise MAPP gas and, in such embodiments, the process may provide a substantially pure stream of propane as a further product, in addition to the chlorinated propanes and/or propenes. The process desirably comprises at least one dehydrochlorination step. The chlorination agent comprises chlorine, S0 ₂ C1 ₂ , or combinations of these. The chlorinated propene produced desirably comprises from 3 to 4 chlorine atoms, and in some embodiments, may be 1, 1,2,3-tetrachloropropene. In those embodiments wherein a chlorinated propane is desirably produced, the chlorinated propane may comprise from 3 to 5 chlorine atoms. HC3 is generated by the process as a by-product, and in some embodiments, may be recovered in its anhydrous form for use, e.g., in downstream processes.

[0009] The advantages provided by the present processes may be carried forward by utilizing the chlorinated propenes or higher alkenes to produce further downstream products, such as, e.g., 2,3 ,3 ,3-tetrafluoroprop- 1 -ene (HFO-1234yf).

[0010] DESCRIPTION OF THE FIGURES

[001 1] FIG. 1 shows a schematic diagram of a process according to one embodiment;

[0012] FIG. 2 shows a schematic diagram of a process according to another embodiment;

[0013] FIG. 3 shows a schematic diagram of a process according to another embodiment;

[0014] FIG. 4 shows a schematic diagram of a process according to another embodiment;

[0015] FIG. 5 shows a schematic diagram of a process according to another embodiment;

[0016] FIG. 6 shows a schematic diagram of a process according to another embodiment; and

[0017] FIG. 7 shows a schematic diagram of a process according to another embodiment. DETAILED DESCRIPTION

[0018] The present specification provides certain definitions and methods to better define the present invention and to guide those of ordinary skill in the art in the practice of the present invention. Provision, or lack of the provision, of a definition for a particular term or phrase is not meant to imply any particular importance, or lack thereof. Rather, and unless otherwise rsoted, terms are to be understood according to conventional usage by those of ordinary skill in the relevant art.

[0019] The terms "first", "second", and the like, as used herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Also, the terms "a" and "an" do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item, and the terms "front", "back", "bottom", and/or "top", unless otherwise noted, are merely used for convenience of description, and are not limited to any one position or spatial orientation.

[0020] if ranges are disclosed, the endpoints of all ranges directed to the same component or property are inclusive and independently combinabie (e.g., ranges of "up to 25 wt.%, or, more specifically, 5 wt.% to 20 wt.%," is inclusive of the endpoints and all intermediate values of the ranges of "5 wt.% to 25 wt.%," etc). As used herein, percent (%) conversion is meant to indicate change in molar or mass flow of reactant in a reactor in ratio to the incoming flow, while percent (%) selectivity means the change in molar flow rate of product in a reactor in ratio to the change of molar flow rate of a reactant.

[00211 Reference throughout the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment. Thus, the appearance of the phrases "in one embodiment" or "in an embodiment" in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments,

[0022] Further, "MAPP" may be used as an abbreviation for a gas comprising methylacetylene and one or more of propadiene, propene and/or propane whether stabilized or destabilized, "PDC" may be used as an abbreviation for 1 ,2-dichioropropane, "TCP" may be used as an abbreviation for 1,2,3-trichloropropane and "TCPE" may be used as an abbreviation for 1, 1 ,2,3-tetrachloropropene.

[0023] The present invention provides efficient processes for the production of chlorinated propanes and/or propenes. The present processes comprise conducting successive chlorination and dehydrochlorination steps on a feed stream comprising methylacetylene. While the use of methylacetylene, a byproduct in many processes for the production of ethylene and propylene, as a starting material is economically more attractive than disposing of it via incineration or using it as fuel, as is conventional, those of ordinary skill in the art have yet not considered methylacetylene for use as a feed stream for any process, much less one for the production of chlorinated propanes and/or propenes due, at least in part to its highly exothermic nature. The fact that methylacetylene is most commonly provided in combination with, e.g., propane, propadiene and/or propene further discourages serious consideration its use as a starting material.

[0024] It has now been discovered that methylacetylene, whether provided alone or in combination with propadiene, propene and/or propane, i.e., as MAPP gas, can be used as a feedstream in processes for the production of chlorinated propanes and/or propenes, thereby allowing the recovery of greater economic value from this byproduct than previously thought possible. In fact, it is a. further advantage of the invention that the provided processes can provide a substantially purified stream of a second commercially useful product in addition to the chlorinated propane and/or propene, i.e., propane, in those embodiments wherein the methylacetylene is provided in the form of MAPP gas.

[0025] And, because conversions of greater than 90% or even full conversion of methylacetylene do not result in the formation of large amounts of undesirable secondary products, the present processes may be conducted in reactors that utilize the heat generated by the reaction. In contrast, in processes for the production of chlorinated propanes and/or propanes that utilize conventional starting materials, wherein greater than 90% conversion of the starting materials is not desired, heat must be removed by more capital intensive means (such as the use of shell and multitube heat exchanger) from the reactors used in the present processes.

[0026] For example, in some embodiments, boiling bed reactors may be utilized in the present processes. Boiling bed reactors use the heat of reaction in order to evaporate components of the feed stream, e.g., methylacetylene. Boiling bed reactors may thus be used in those embodiments wherein the methylacetylene is provided as MAPP gas, and in such embodiments, may act in essence as a distillation column and provide for the separation of a substantially pure stream of propane from the MAPP gas. Because heat is managed and desirably utilized, rather than being removed from, the present processes, continuous operation of the processes is possible, as is not typically the case when conventional starting materials are used in conventional reactors. [0027] The present process is further advantageous since, in some embodiments, useful intermediates and/or a saleable product can be reached in fewer steps, resulting in lower capital costs as compared to conventional processes. And, in some embodiments, a reduction of caustic cracking steps as compared to conventional processes for the production of chlorinated propanes and/or propenes means that a greater amount of anhydrous HCi can be recovered. Anhydrous HCI is of greater value than the sodium chloride produced as a secondary product in conventional processes for the production of chlorinated propanes and/or propenes employing multiple caustic cracking steps. And so, the present process results in the production of a secondary product that may either be sold or used as a feedstock for other processes, e.g., ethylene oxychlorination to produce ethylene dichloride.

[0028] In some embodiments, the present processes may comprise liquid phase chlorination reactions, using ionic chlorination or eiectrophilic addition of chlorines to olefins. Liquid phase chlorinations may provide advantages as compared to conventional methods for producing chlorinated propanes and/or propenes using gas-phase thermal chlorination reactions because the production utility cost is lower for a process comprising liquid phase reactions, where evaporation of reaciants is not required, in addition, the lower reaction temperatures used in the present liquid phase reactions tend to result in lower fouling rates than the higher temperatures used in connection with gas phase reactions. Higher fouling rates, in turn, tend to limit reactor lifetime and can lead to undesirable byproduct formation.

[0029] The present process can make use of a feed stream comprising methylacetylene, either alone or in combination with one or more of propadiene, propene and/or propane. Such a feedstream may be available at low cost due to its production as a by-product in many processes for the production of ethylene and propylene. And so, the ieedstream may advantageously be generated within, or upstream of, the process, if desired, by any methods known to those of ordinary skill in the art. The process feedstock may also comprise trichloropropane, other chlorinated alkanes, or other reactants and reaction byproducts, if desired.

[0030] Any chlorinated propane and/or propene may be produced using the present method, although propanes with 3-5 chlorine atoms and propenes with 3-4 chlorine atoms are more commercially sought after, and production of the same may thus be preferred in some embodiments. In some embodiments, the process may be used in the production of 1,1,2,3- tetrachloropropene, which is highly sought after as a feedstock for retrigerants, polymers, bioeides, etc,

[00311 The chlorination steps of the process may be carried out using any chlorination agent, and several of these are known in the art. For example, suitable chlorination agents include, but are not limited to chlorine, and/or sulfuryl chloride (S0 ₂ C1 ₂ ). Of these, chlorine may be particularly suitable for use in gas phase chlorinations, while both Cl ₂ and sulfur}'! chloride may be particularly suitable for use in liquid phase chlorinations. If sulfuryl chloride is used, the by-product S0 ₂ may be catalytically recombined with Cl ₂ to regenerate sulfuryl chloride that may then be recycled to the process. Further, in such embodiments, the sulfuryl chloride may advantageously act as a diluent/solvent for the reaction, and thereby enhance the efficacy of any catalysts used in the process.

[0032] Catalysts are not required for the chlorination steps of the present process, but can be used, if desired, in order to increase the reaction rate. Suitable free radical chlorination catalysis include, but are not limited to, compounds comprising one or more azo-groups (R- N=N-R') such as azobisisobutyronitrile (AIB ) or 1 , 1 '-azobis(cyclohexanecarbonitrile) (ABCN) and organic peroxides such as di-tert-butyl peroxide, benzoyl peroxide, methyl ethyl ketone peroxide, and acetone peroxide. In some embodiments, the use of benzoyl peroxide may be preferred, either alone or in combination with UV or visible light or heat. Such catalysts may also enhance the chlorination of double bonds in olefins or chlorinated olefins to produce ,β chloroalkanes,

[00331 In some embodiments, ionic or electrophiiic chlorination catalysts, may be utilized in one or more chlorination steps. The use of ionic chlorination catalysts in the present process is particularly advantageous since they dehydrochlorinate and chlorinate alkanes at the same time. That is, ionic chlorination catalysts remove a chlorine and hydrogen from adjacent carbon atoms, the adjacent carbon atoms form a double bond, and FICl is released. A chlorine molecule is then added back, replacing the double bond, to provide a higher chlorinated alkane. Ionic chlorination catalyst also promote the addition of chlorines to double bonds in olefins or chlorinated olefins to produce α,β chloroalkanes at high yield.

[0034] Ionic chlorination catalysts are well known to those of ordinary skill in the art and any of these may be used in the present process. Exemplary ionic chlorination catalysts include, but are not limited to, Lewis acids, such as compounds comprising aluminum (e.g., aluminum chloride), iron (ferric chloride), iodine, chlorine and sulfur, etc. If catalysts are to be utilized in one or more of the chlorination steps of the present process, the use of ionic chlorination catalysts, such as AlC and I ₂ , can be preferred.

[0035] In other embodiments of the present process, the use of catalysts in the chlorination steps is not required. Nonetheless, any suitable catalyst(s) can be used, if desired, in order to increase the reaction rate.

[0036] The dehydrochlorination steps of the present process may similarly be conducted without a catalyst, in the presence of a liquid caustic. Many chemical bases are known in the art to be useful for this purpose, and any of these can be used. For example, suitable cracking bases include, but are not limited to, alkali metal hydroxides, such as sodium hydroxide, potassium hydroxide, calcium hydroxide; alkali metal carbonates such as sodium carbonate; lithium, rubidium, and cesium or combinations of these. Phase transfer catalysts such as quaternary ammonium and quaternary phosphonium salts can also be added to improve the dehydrochlorination reaction rate with these chemical bases.

[0037] Alternatively, in some embodiments, the dehydrochlorination steps of the present process may be carried out in the presence of a catalyst so that the reaction rate is enhanced and also use of liquid caustic is reduced, or even eliminated, from the process. If the use of catalysts is desired, suitable dehydrochlorination catalysts include, but are not limited to, ferric chloride (FeCU). Ferric chloride, for example, can be used to dehydrochlorinate 1, 1, 1, 2,3 -pentachloropropane to TCPE, while combinations of aluminum chloride and iodine can be used to dehydrochlorinate 1 , 1,2,2, 3-pentachioropropane to TCPE.

[0038] Any or all of the chlorination and/or dehydrochlorination catalysts can be provided either in bulk or in connection with a substrate, such as activated carbon, graphite, silica, alumina, zeolites, fluorinated graphite and fluorinated alumina.

[0039] The amount of any chlorination catalyst and/or dehydrochlorination catalyst utilized will depend upon the particular catalyst chosen as well as the other reaction conditions. Generally speaking, in those embodiments of the invention wherein the utilization of a catalyst is desired, enough of the catalyst should be utilized to provide some improvement to reaction process conditions (e.g., a reduction in required temperature) or realized products, but yet not be more than will provide any additional benefit, if only for reasons of economic practicality. [0040] For purposes of illustration only, then, it is expected in those embodiments wherein an ionic chlorination catalyst, e.g., comprising, FeCU, Aids and/or ¾, is used, that usefui concentrations of each will range from 0,001 % to 20% by weight each with respect to chlorinated propanes or olefins or chlorinated olefins, or from 0.01% to 10%, or preferably from 0.1% to 5 wt.%, inclusive of all subranges there between. If a dehydrochlorination catalyst, e.g., FeCU, is utilized, useful concentrations may range from 0.01wt% to 5wt%, or from Q.G5wt% to 2wt% at temperature of 70'C to 2QG°C, If a chemical base is utilized for one or more dehvdrochlorinations, usefui concentrations of these will range from 0.01 to 20 grmole L, or from 1 grmole L to 10 grmole/L, inclusive of all subranges there between.

[0041 ] In additional embodiments, one or more reaction conditions of the process may be optimized, in order to provide even further advantages, i.e., improvements in selectivity, conversion or production of reaction by-products. In certain embodiments, multiple reaction conditions are optimized and even further improvements in selectivity, conversion and production of reaction by-products produced can be seen.

[0042] Reaction conditions of the process that may be optimized include any reaction condition conveniently adjusted, e.g., that may be adjusted via utilization of equipment and/or materials already present in the manufacturing footprint, or that may be obtained at low resource cost, Examples of such conditions may include, but are not limited to, adjustments to temperature, pressure, flow rates, molar ratios of reactants, etc.

[0043] That being said, the particular conditions employed at each step described herein are not critical, and are readily determined by those of ordinary skill in the art. What is important is that the feedstream comprise methylacetylene, either alone or in combination with propadiene and/or propane. It is also advantageous that at least one dehydrochlorination step be conducted catalytically, e.g., with Fe(¾, rather than by using liquid caustic, so that anhydrous HQ is produced and the production of sodium chloride is minimized. Further advantages may be provided in those embodiments in which chlorinations are conducted in the liquid phase and/or wherein more than one reaction is carried out within at least one reactor. Those of ordinary skill in the art will readily be able to determine suitable equipment for each step, as well as the particular conditions at which the purification, drying, chlorination, cracking and isomerization steps described herein. [0044] in the present process, a feedstream comprising methylaeetylene is converted to TCPE, or an intermediate thereof, using a series of consecutive chlorination and/or dehydrochlorination steps. In one exemplary embodiment, a feedstream comprising methylaeetylene is fed to a boiling bed reactor, e.g., such a batch or continuous stirred tank reactor with or without an internal cooling coil. Suitable reaction conditions include, e.g., a temperature of from 80°C to 180°C, a pressure of from 100 kPa to lOOOkPa. The reaction may desirably be carried out without a. catalyst or, in other embodiments, one or more ionic chlorination catalysts such as ferric chloride, may be used. Desirably, feedstream conversion, e.g., of methylaeetylene either alone or in combination with one or more of propadiene, propene and/or propane, will be greater than 80%, or greater than 90%, or greater than 95%, or close to 100%.

[0045] A schematic illustration of such a process is shown in Figure 1. As shown in Figure 1, process 100 would make use of chlorination reactors 102, 110, 112, and 1 18; separation units 104, 106, 108, 1 14, 1 16 and 120; cracking reactor 122, dryer 124 and isomerization reactor 126. In operation, methylaeetylene, either alone or in combination with one or more of propadiene, propene and/or propane, the desired chlorination agent (e.g., chlorine, S0 ₂ C1 ₂ , or combinations of these) and, in some embodiments, one or more catalysts are fed to boiling bed chlorination reactor 102, which may be operated at any set of conditions suitable to provide for the chlorination of the feedstream to a mixture of tetrachloropropanes and trichloropropenes, as well as smaller portions of dichloropropane, monochloropropanes, and monochloropropenes if propane or propene is present in the feedstream. In some embodiments, chlorination reactor 102 may comprise dichloropropane, trichloropropene and/or tetrachioropropane as a boiling bed solvent to maintain the reaction temperature at from 80°C to 180°C, at pressures at or greater than atmospheric. Operated at such conditions, chlorination reactor 102 is expected to chlorinate the feedstream to a mixture comprising tetrachloropropanes, trichloropropenes, dichloropropane and small amounts of monochloropropanes, monochloropropenes and HQ.

[0046] The overhead stream of reactor 102, expected to comprise unreacied propane and propene (if present in the feedstream), Ch, HC1, PDC, monochloropropanes and monochloropropenes, is provided to separation unit 104. Separation unit 104 is operated at conditions effective to provide HC1 and hydrocarbons in an overhead stream thereof to separation unit 106, while the bottom stream from separation unit 104, expected to comprise chlorine and chlorinated organic intermediates, is recycled back to chlorination reactor 102.

[00471 The overhead vapor stream of separation unit 104 is cooled, condensed and fed to separation unit 106, which may desirably be a distillation column. Separation unit 106 is operated at conditions effective to provide anhydrous HCl overhead and a bottoms stream of hydrocarbons.

[0048] The product stream of chlorination reactor 102, comprising chlorinated organic products is delivered to separation unit 108. Separation unit 108, in turn, separates the product stream into a. stream comprising monochloropropenes and mono- and di- chloropropanes, which is delivered to chlorination reactor 1 10, and a stream of 1,2,3- trichloropropene, trichloropropenes and heavier byproducts which is delivered to separation unit 1 14,

[0049] Chlorination reactor 1 10 provides for the free radical chlorination (using an initiator such as AIBN) of the monochloropropenes, mono- and di-chloropropanes to di and tri-chloropropanes as well as smaller amounts of tetra- and pentachloropropanes, using suitable conditions known to those of ordinary skill in the art.

[0050] The overhead stream of chlorination reactor 1 10, expected to comprise HCl, excess Cl ₂ , and a small fraction of unreacted monochloropropenes, and mono- and dichloropropanes, is recycled to separation unit 104, while the bottoms stream of chlorination reactor 1 10 comprising the chlorination products is recycled back to separation unit 108.

[0051] The bottoms stream 150 from separation unit 108, expected to comprise 1,2,3- trichloropropene, trichloropropanes and heavier byproducts is fed to separation unit 114. Separation unit 1 14 is operated at conditions effective to recover 1 ,2,3-trichloropropene and a small fraction of tri- and tetrachloropropanes in an overhead stream which is then fed to chlorination reactor 112.

[0052] Chlorination reactor 1 12 provides for the ionic or free radical chlorination of 1 ,2,3- trichloropropene to 1 , 1,2,2,3-pentachloropropa.ne. Unreacted chlorine, as well as any light chlorinated organics and/or unreacted reactants, is/are recycled in the overhead stream thereof to separation unit 104. The heavier chlorinated products generated by chlorination reactor 112, expected to comprise peniachloropropanes and excess trichloropropene, are recycled to column 1 14.

[00531 The bottom stream of column 1 14, expected to comprise tri-, tetra- and peniachloropropane intermediates, is fed to separation unit 1 16. Separation unit 1 16 is operated at conditions effective to provide an overhead stream comprising tri-and tetrachloropropane and a bottoms stream comprising peniachloropropanes and heavier byproducts. The overhead stream is fed to liquid chlorination reactor 1 18, while the bottoms stream is fed to separation unit 120.

[0054] Chlorination reactor 118 provides for the free radical chlorination of the tri- and tetraehloropropanes (using an initiator such as, e.g., dibenzoyl peroxide) to produce the desirable pentachloropropane isomers, i.e., 1 , 1 ,2,2,3-pentachloropropane, 1 , 1 , 1,2,3- pentachloropropane and 1, 1 ,1,2,2-penta.chloropropane. Unreacted chlorine and HC1 from chlorination reactor 118 is recycled back to column 104, while the bottoms stream of chlorination reactor 1 18 comprising the peniachloropropane isomers is recycled back to separation unit 1 6.

[0055] Separation unit 120 separates the bottom stream 164 from column 1 16 into an overhead stream comprising the desirable pentachloropropane isomers (1, 1 ,1,2,2- peniachloropropane, 1 , 1,2,2,3-pentachloropropane and 1 ,1, 1,2, 3 -pentachloropropane) and a bottom stream comprising the less desirable 1,1 ,2,3,3-pentachloropropane, hexachloropropane and heavier by-products. The overhead stream is fed to cracking reactor 122, while the bottoms stream is appropriately disposed of.

[0056] Within cracking reactor 122, the desirable pentachloropropane isomers are caustic cracked using sodium hydroxide to provide 2,3,3,3-tetrachloropropene and 1 , 1 ,2,3- tetrachlropropene, and the conditions to do so are either well-known, or readily determined, by those of ordinary skill in the art. Generally speaking then, cracking reactor 122 may be charged with caustic soda at 50% aqueous solution at concentration of from 0.01 grmole/L to 20 grmole/L, or from 0.1 grmole/L to lOgrmole/L, and operated at pressures of from ambient to 40GkPA and temperature of from 40°C to 150°C, or from 60°C to 120°C and at residence time less than 3 hours. The product stream of cracking reactor 122 is fed to drying unit 124, and then to isomerizing reactor 126, wherein the dried 2,3,3,3-tetrachloropropene is isomerized to TCPE using catalyst as described in U.S. Patent No. 3,926,758. [0057] A schematic illustration of another embodiment of the process is shown in Figure

2. As shown in Figure 2, process 200 would utilize chlorination reactors 202, 210, 212 and 2.1 8; separation units 204, 206, 208, 214, 216, 220 and 283; cracking reactors 222 and 282; dryer 224 and isomerization reactor 226. The process as shown in Figure 2 operates in much the same way as process 100, and like structures are numbered alike, but incremented by 100, and not discussed further. The embodiment represented by Figure 2 provides the additional advantage of allowing greater recovery of anhydrous HC1 by virtue of the inclusion of additional cracking reactor 282, desirably operated as a catalytic cracking reactor rather than a caustic cracking reactor and separation unit 283 ,

[00581 In process 200, the overhead stream from separation unit 220 is fed to cracking reactor 282, which is desirably a catalytic cracking reactor. Cracking reactor 282 is thus charged with an appropriate catalyst, e.g., FeCl ₃ , and the desirable pentachloropropane isomer 1 , 1 , 1 ,2,3 -pentachloropropane cracked to provide 1 , 1,2,3-tetrachlropropene and anhydrous HC1. For example, catalytic cracking reactor 282 may be charged with FeCl ₃ at concentration of from 0.01% to 5% by weight, or from 0.1% to 8%, and operated at pressures of from l OOkPa to l OOOkPa and temperature of from 70°C to 200°C, or from 90°C to 160°C and at residence times of less than 3 hours.

[00591 The HC3 byproduct from catalytic cracking reactor 282 is recycled to column 204 for recovery. The product of cracking reactor 282 comprising 1 , 1 ,2,3-tetrachloropropene and unconverted pentachloropropane isomers is fed to a separation unit 283 to recover the desired product, e.g., 1 , 1,2,3-tetrachloropropene, in an overhead stream. The remaining pentachloropropane intermediates are fed to the caustic cracking reactor 222, and the remaining portion of process 200 proceeds as described in connection with Figure 1.

[00601 A schematic illustration of another embodiment of the process is shown in Figure

3. As shown in Figure 3, process 300 would utilize chlorination reactors 302 and 310; separation units 304, 306, 308, 3 14, 3 16, 320 and 383 ; cracking reactors 322 and 382; dryer 324 and isomerization reactor 326. The process as shown in Figure 3 operates in much the same way as process 200, and like structures are numbered alike, but incremented by 100, and not discussed further. The process as shown in Figure 3 combines chlorination reactors 202 and 212 (into chlorination reactor 302) and chlorination reactors 210 and 2.1 8 (into chlorination reactor 310) from process 200, thereby eliminating two chlorination reactors. [0061 ] in process 300, the overhead stream of separation units 314, comprising trichloropropenes, is recycled to reactor 302 (instead of feeding to reactor 212 as shown in Figure 2) for conversion to pentachioropropane together with methylacetylene and optionally, propadiene. And, the overhead stream 360 of separation unit 316 comprising tetrachloropropanes can be recycled to chlorination reactor 310 (rather than being fed to reactor 218 as shown in Figure 2) where free radical initiator is used to produce pentachloropropanes. The remainder of process 300 proceeds as described in connection with process 200 shown in Figure 2.

[0062] Yet another embodiment of the process is shown in Figure 4. As shown in Figure 4, process 400 would utilize chlorination reactor 402 and 412, separation units 404, 414, 416 and 420, cracking reactors 422 and 482, dryers 424 and 484 and isomerization reactor 426. In operation, a feedstream comprising methylacetylene, either alone or in combination with propadiene is fed to liquid phase chlorination reactor 402. Liquid phase chlorination reactor 402 utilizes trichloropropene and tetrachloropropane(s) as boiling bed solvents to maintain the reaction temperature at from 80°C to 180°C, at pressures at or greater than atmospheric. Operated at such conditions, chlorination reactor 402 is expected to chlorinate the feedstream (with or without the addition of an ionic chlorination catalyst such as FeCU) to provide a mixture comprising tetrachloropropanes, trichloropropenes, and HC3.

[0063] The overhead product stream from chlorination reactor 402 is fed to separation unit 404 via line 430 to recover anhydrous HC1 in stream 432, while a small fraction of trichloropropene(s) and tetrachioropropane(s) as well as any unreacied chlorine, methylacetylene and/or propadiene are recycled back to reactor 402. The product stream from chlorination reactor 402, comprising trichloropropenes and tetraehloropropane(s), is fed to a separation unit 414.

[0064] Separation unit 414 is operated at conditions effective to provide an upper stream comprising trichloropropenes and a bottoms stream comprising tetrachloropropanes. The upper stream from separation unit 414 is fed to chlorination reactor 412, while the bottoms stream from separation unit 414 is fed to further separation unit 416.

[0065] Liquid phase chlorination reactor 412 chlorinates the trichloropropenes to produce pentachloropropanes. Excess chlorine is recovered from chlorination reactor 412 in the overhead stream and recycled to separation unit. 404. The product stream from chlorination reactor 412, comprising the pentachloropropane and unreacted trichloropropenes is recycled to separation unit 414.

[00661 The bottom stream 458 of column 414, now comprising the tetrachloropropanes and pentachloropropane intermediates, is fed to separation unit 416. Separation unit 416 provides an overhead stream comprising the tetrachloropropanes which is fedto caustic cracking reactor 482 and a bottoms stream comprising the pentachloropropane intermediates which is fed to separation unit 420.

[0067] Caustic cracking reactor 482 produces trichloropropene isomers, water and sodium chloride. The water and salt are removed in a drying unit 484 and the trichloropropene intermediates are recycled to chlorination reactor 412. The bottom stream of purification unit 416, comprising pentachloropropanes and heavier byproducts, is fed to separation unit 420. Separation unit 420 provides the desired pentachloropropane isomers in an overhead stream, while the heavier byproducts 1, 1,2,3,3-pentachloropropane and heavier byproduct are purged.

[0068] The desirable pentachloropropane intermediates are fed to caustic cracking reactor 422, which cracks the pentachloropropanes to provide a stream of tetrachloropropenes, water and sodium chloride. This product stream is provided to drying unit 424, wherein the salt and water are removed and purged. The purified tetrachloropropenes (2,3,3,3-tetrachloropropene and TCPE) are fed to isomerization reactor 426 to produce TCPE.

[0069] Yet another embodiment of the process is shown in Figure 5. As shown in Figure 5, process 500 would utilize chlorination reactor 502, separation units 504, 514, 516 and 520; cracking reactors 522 and 582, dryers 524 and 584 and isomerization reactor 526. The process as shown in Figure 5 operates in much the same way as process 400, shown in Figure 4, with the exception that chlorination reactors 402 and 412 are combined into one chlorination reactor 502 in process 500.

[0070] And so, in operation, the overhead stream of purification unit 514 is recycled back to reactor 502 to be further chlorinated to pentachloropropane, rather than being fed to chlorination reactor 412 as in process 400. Similarly, the trichloropropene isomers in the overhead stream 586 of drying column 584 is recycled to reactor 502, rather than being fed to chlorination reactor 412 as in process 400. The rest of process 500 proceeds as described above in connection with process 400. [0071 ] A schematic illustration of another embodiment of the process is shown in Figure

6. As shown in Figure 6, process 600 would utilize chlorination reactors 602, 612 and 618, separation units 604, 614, 616 and 620, cracking reactor 622, dryer 624 and isomerization reactor 626. The process as shown in Figure 6 operates in much the same way as process 400, shown in Figure 4, with the exception that caustic cracking reactor 418 and dryer 484 are not utilized in process 600, so that the tetraehloropropane intermediate(s) provided by purification unit 616 via line 660 is/are chlorinated in chlorination reactor 618 to provide a mixture of pentachloropropane(s). Process 600 thus allows for the recovery of more anhydrous HQ than process 400.

[00721 Desirably, chlorination reactor 618 is operated at conditions sufficient to provide a conversion of the tetraehloropropane intermediates of less than 60%. HC1 and excess chlorine from chlorination reactor 618 are fed to separation unit 604 via line 656, while the product stream, comprising pentachloropropane(s) and nreacted tetraehloropropane, is recycled back to separation unit 6 6.

[0073] A schematic illustration of another embodiment of the process is shown in Figure

7. As shown, process 700 would utilize chlorination reactors 702 and 718, separation units 704, 714, 716 and 720, cracking reactor 722, dryer 724 and isomerization reactor 726. The process as shown in Figure 7 operates in much the same way as process 600, shown in Figure 6, with the exception that chlorination reactors 602 and 612 are combined into one chlorination reactor 702 in process 700. And so, in operation, process 700 recycles overhead stream 752, comprising trichioropropenes to chlorination reactor 702, rather than feeding overhead stream 752 to a separate chlorination reactor (e.g., chlorination reactor 612 in process 600),

[0074] The chlorinated propanes and/or propenes produced by the present process may typically be processed to provide further downstream products including hydrofluoroolefms, such as, for example, 1 ,3 ,3 ,3-tetrafluoroprop- 1 -ene (ITFO-1234ze). Since the present invention provides an improved process for the production of chlorinated propanes and/or propenes, it is contemplated that the improvements provided will carry forward to provide improvements to these downstream processes and/or products. Improved methods for the production of hydrofluoroolefms, e.g., such as 2,3 ,3 ,3-tetrafluoroprop- 1 -ene (HFO-1234yf), are thus also provided herein. [0075] The conversion of chlorinated propenes to provide hydrofiuoroolefms may broadly comprise a single reaction or two or more reactions involving fluorination of a compound of the formula C(X).„CCl(Y) _n (C)(X) _m to at least one compound of the formula CF ₃ CF=CHZ, where each X, Y and Z is independently H, F, CL I or Br, and each m is independently 1, 2 or 3 and n is 0 or 1. A more specific example might involve a multi-step process wherein a feedstock of a chlorinated propene is ftuorinated in a catalyzed, gas phase reaction to form a compound such as l-chloro-3,3,3 -trifluoropropene (1233zd). The l -chioro-2,3,3,3- tetrafluoropropane is then dehydrochiorinated to 1 ,3,3,3-tetrafluoropropene via a catalyzed, gas phase reaction.

[00761 Some embodiments of the invention will now be described in the following Examples.

[0077] Example I

[0078] 8gr of chlorine gas and methylacetylene gas at molar ratio of 4/1 chlorine to methylacetylene is sparged for 30 minutes in a 100 ml mixture of 50/50 mole% of 1, 1 ,2,2- tetrachloropropane and 1,2,2,3-tetrachloropropane as a solvent heated in a water bath and stirred to maintain the temperature at 60-80°C. A reflux column is placed to return solvent, unreacted chlorine and product. The product of the reaction is expected to contain 15 mole% 1,2,3-trichloropropene, 20 mole% 1,2,2,3-tetrachloropropane, and 65 moie% 1, 1,2,2- tetrachloropropane.

[0079] A stream comprising 1,2,3-trichloropropene is separated from the mixture by vacuum distillation while the reboiier temperature is kept below 150°C. The stream of 1,2,3- trichloropropene is chlorinated by providing it to a continuous flow stirred tank liquid phase chiorination reactor with a cooling coil, operating at a temperature of 40 "C to 60 °C and at atmospheric pressure with a slightly molar excess of chlorine using UV light. The product, 1, 1,2,2, 3-pentachloropropane, is obtained after less than 3.5 hr of reaction time.

[0080] The remaining tetrachloropropane intermediates are fed to a third liquid phase chiorination reactor. Chlorine and 1000 ppm of dibenzovl peroxide are added to produce 40% conversion of tetrachloropropane after less than 1 hour, at a temperature of 40°C to 50°C. The product mixture is expected to have less than 10wt% of hexachloropropane. [0081 ] This product mixture (comprising unreacted tetrachloropropane, pentachloropropane, and hexachloropropanes) is distilled by a second separation unit operated a subatmospheric pressure with a reboiler temperature below 170°C to recover unreacted tetrachloropropanes in the overhead stream. This stream is then recycled to the third chlorination reactor.

[0082] The remaining desirable 1 , 1 ,2,2,3-pentachloropropane and 1, 1 ,1 ,2,2- pentachloropropane are separated in the overhead stream of a third separation unit from the undesired liexachloropropane and heavy bottom stream under vacuum and with a reboiler temperature of less than 199°C. The overhead stream comprising pentachloropropane isomers are caustic cracked to TCPE and 2,3,3,3-tetrachloropropene at 40°C-50°C using caustic soda solution of 10-20% wt.%. After drying, the product (comprising TCPE and 2,3,3,3-tetrachloropropene) is sent to an isomerization reactor to produce TCPE.