Selective adsorption of halocarbon impurities containing Cl, Br and I in fluorocarbons or hydrofluorocarbons using adsorbent-supported metal oxides

Abstract

A method for purifying a fluorocarbon or hydrofluorocarbon containing at least one undesirable halocarbon impurity comprises flowing the fluorocarbon or hydrofluorocarbon through at least one adsorbent bed to selectively adsorb the at least one undesirable halocarbon impurity through physical and / or chemical adsorption, the at least one adsorbent bed containing a metal oxide supported on an adsorbent in an inert atmosphere.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Patent Application Publication No. 17 / 192,421, filed March 04, 2021, which is incorporated by reference in its entirety for all purposes.

[0002] The present invention relates to a method for selective adsorption of halocarbon impurities, including Cl, Br, and I, in fluorocarbons (FCs) or hydrofluorocarbons (HFCs) using a metal oxide supported sorbent, and in particular to a method for purifying fluorocarbons or hydrofluorocarbons and removing undesirable impurities. [Background technology]

[0003] In the chemical industry, standard fluorocarbons (FCs) or hydrofluorocarbons (HFCs) commonly used as refrigerants contain silica (SiO 2 ), Alumina (Al 2 O 3 Fluorinated hydrocarbons are produced by the high temperature fluorination of halocarbons or hydrocarbons containing Cl, Br and I in the presence of metals or metal oxides supported on porous materials such as fluorinated fluorocarbons (FCs), supported on porous materials such as fluorinated fluorocarbons (H ... 2 / HF→HFC+by-products.

[0004] For example, U.S. Patent No. 5,545,774 issued to V. Rao discloses the preparation of 1,1,1,3,3,3,3-hexafluoropropane (236fa or trade name FE-36) by reacting 1,1,1,3,3,3,3-hexachloropropane with HF in the presence of a carbon-supported trivalent chromium compound at temperatures of about 250-400° C. U.S. Patent No. 5,574,192 issued to VanDerPuy et al. discloses the preparation of CCl 3 in the presence of a fluorination catalyst such as a metal halide. 3 CH 2 CHCl 2 , C.F. 3 CH 2 CHCl 2 , CFCl 2 CH 2 CHCl 2 US Pat. No. 5,393,636 discloses a process for producing 1,1,1,3,3-pentafluoropropane (245fa or HFC-245fa, also known by the trade names Enovate and Genetron) by reacting an HCFC compound such as HF.

[0005] The use or presence of these impurities needs to be restricted at various concentration levels ranging from percent to ppm levels depending on the severity of the damage to the above causes. However, some of these contaminants can be difficult to separate using more widely used processes such as distillation due to azeotropic interactions with the main product. Although different methods have been disclosed for the separation of important halocarbon impurities containing Cl, Br and I from some of the HFC molecules, including the molecules of the present invention, there is no one universal process developed for all of the above impurities that can be applied to different molecules.

[0006] For example, US 2012 / 0323054 (J. Knapp) discloses the separation of cis-1,1,1,4,4,4-hexafluoro-2-butene from a mixture containing one or more chlorofluoroolefins by the addition of an extractant, which changes the relative volatility of the cis-compounds relative to the chloroolefins, making them easier to purify using distillation.

[0007] EP 0 508 631 A1 (P. Clayton) discloses a process for the preparation and purification of hydrofluoroalkanes from chloro compounds and halohydrofluoroalkanes by passing these compounds in the vapor form through a solution of a complex metal hydride in combination with an alkali halide.

[0008] US Patent Publication No. 2004 / 0030204 (Wilmet et al.) discloses the reaction of HF, Cl in the presence of an initiator, 2 A more versatile hydrofluoroalkane purification is disclosed which includes different methods for removing olefinic impurities, including treatment with toluene, adsorption on solid adsorbents (alumina and silica), distillation and reactive distillation.

[0009] U.S. Pat. No. 6,815,568 (Horiba et al.) discloses a process for purification of octafluorocyclobutane to obtain a product by reaction of the crude product containing chloro impurities with decomposition agents (iron oxides and alkaline earth compounds) at high temperature, followed by adsorption with coal tar, molecular sieves or activated carbon.

[0010] U.S. Pat. No. 5,852,223 (Kohno et al.) describes a method for reducing CFCs in hydrofluoroalkanes, which comprises converting the compounds into H 2 A method is disclosed in which the mixture is reacted with a gas and the mixture is separated using distillation.

[0011] Many other patents claim similar purification methods for different fluorocarbons or hydrofluorocarbons.

[0012] In Adsorption Basics Part 1 and Part 2 (2017 CEP Magazine, American Institute of Chemical Engineers), A. Gabelman describes the basic operation, design, and mechanisms of adsorption processes, including regeneration of the adsorbent bed. Regeneration of the adsorbent bed can be accomplished by contacting the adsorbent with a gas or liquid that contains little or no adsorbates (impurities), by contacting the adsorbent bed with a solvent that has a higher affinity than the adsorbates, or by increasing the temperature or reducing the pressure of the adsorbent. Silica gel and activated alumina (Al 2 O 3 ) can be used to dry gases or liquids. Silica gel can be regenerated at 120°C. Zeolite molecular sieves 3A, 4A, 5A and 13X can be used to remove various impurities including water, which can be regenerated at 200-300°C.

[0013] The use of sorbents including alumina, silica, etc. to adsorb moisture, acid (HF and HCl) solvent vapors, and some other organic contaminants from HFCs is standard practice in the chemical industry. Other important applications include catalytic dehydrohalogenation to produce olefins, similar to those described in US Patent Publication No. 2015 / 126786A (Sharratt et al.) and China Patent Publication No. 101293212A (Liu), respectively, or alumina or metal oxide / metal supported sorbents to crack tail gases to protect the environment.

[0014] US Patent 2,879,228 (Holeton et al.) discloses the use of silica gel and alumina for the partial removal of fluorinated compounds from perfluorinated lubricants in the liquid phase. Korean Patent 100317113 discloses the sequential use of alumina and activated carbon columns for the sequential removal of HF and halocarbon contaminants from an HCl stream. British Patent 2,295,101 (Leppard et al.) discloses the use of chi-alumina beds for the removal of halocarbon contaminants from air streams. Other common applications include the use of adsorbents to remove oil or hydrocarbon contaminants from refrigerants.

[0015] The use of ultra-high purity gases free of impurities is essential for any process requiring good quality control. Particularly for microprocesses including the fabrication of semiconductor devices where the margin of error is extremely narrow, maintaining the purity of the feed gas is crucial to achieve high throughput. Distillation is a more conventional separation technique utilized to achieve this end, however, this process becomes very challenging when the volatility of the impurity in question is close to that of the matrix compound or when azeotropes / quasi-azeotropes are formed with the desired product. Summary of the Invention [Problem to be solved by the invention]

[0016] Thus, a need exists for a method for producing ultra-high purity FC or HFC gases that are free of impurities. [Means for solving the problem]

[0017] A process for the purification of fluorocarbons or hydrofluorocarbons containing at least one undesirable halocarbon impurity is disclosed which comprises flowing the fluorocarbons or hydrofluorocarbons through at least one adsorbent bed to selectively adsorb the at least one undesirable halocarbon impurity through physical and / or chemical adsorption, the at least one adsorbent bed containing a metal oxide supported on an adsorbent in an inert atmosphere.

[0018] A process for purification of a fluorocarbon or hydrofluorocarbon containing at least one undesirable halocarbon impurity is disclosed, comprising the steps of flowing the fluorocarbon or hydrofluorocarbon through at least one adsorbent bed to selectively adsorb the at least one undesirable halocarbon impurity through physical and / or chemical adsorption, wherein the at least one adsorbent bed contains a metal oxide supported on an adsorbent in an inert atmosphere; and distilling the outlet stream of the at least one adsorbent bed to obtain a purified fluorocarbon or hydrofluorocarbon.

[0019] Any of the processes of the present disclosure may include one or more of the following aspects: · further comprising the step of distilling the outlet stream of at least one of the adsorbent beds to obtain a purified fluorocarbon or hydrofluorocarbon; the at least one undesirable halocarbon impurity comprises a chlorofluorocarbon (CFC), a hydrochlorofluorocarbon (HCFC), and a Cl-containing halide, a Br-containing halide, an I-containing halide, or a combination thereof; · the at least one undesirable halocarbon impurity comprises a halocarbon containing a halogen bonded to carbon that is less electronegative than fluorine; At least one undesirable halocarbon impurity, including a halocarbon containing a halogen bonded to carbon that is less electronegative than fluorine, is adsorbed; · the at least one undesirable halocarbon impurity is a halocarbon containing a halogen bonded to carbon that is less electronegative than fluorine; At least one undesirable halocarbon impurity, which is a halocarbon containing a halogen bonded to carbon that is less electronegative than fluorine, is adsorbed; The halogens having a lower electronegativity than fluorine are Cl, Br and / or I; the at least one undesirable halocarbon impurity comprises a halocarbon containing Cl, Br and / or I bonded to carbon; At least one undesirable halocarbon impurity, including carbon-bonded halocarbons containing Cl, Br and / or I, is adsorbed; the at least one undesirable halocarbon impurity is a halocarbon containing Cl, Br and / or I bonded to carbon; At least one undesirable halocarbon impurity, which is a carbon-bonded halocarbon containing Cl, Br and / or I, is adsorbed; the at least one undesirable halocarbon impurity is a Cl-containing halide, a Br-containing halide, an I-containing halide, or a combination thereof; the at least one undesirable halocarbon impurity is a Cl-containing halocarbon, a Br-containing halocarbon, an I-containing halocarbon, or a combination thereof; · the at least one undesirable halocarbon impurity is a chlorofluorocarbon (CFC) or a hydrochlorofluorocarbon (HCFC); · the at least one undesirable halocarbon impurity is a chlorofluorocarbon (CFC) and a hydrochlorofluorocarbon (HCFC); · at least one undesirable halocarbon impurity is a chlorofluorocarbon (CFC); · at least one undesirable halocarbon impurity is a chlorofluorocarbon (CFC); At least one undesirable halocarbon impurity is 2-chloro-1,1,1-trifluoroethane (C 2 H 2 F 3 Cl); At least one undesirable halocarbon impurity is 2-chloro-1,1,3-trifluoropropene (C 3 H 2 F 3 Cl); At least one undesirable halocarbon impurity is 2-chloro-1,1,1,2-tetrafluoropropane (C 2 HF 4 Cl); At least one undesirable halocarbon impurity is 2-chloro-1,1,1,3,3-pentafluoro-1-propene (C 3 F 5 Cl); At least one undesirable halocarbon impurity is 1,1,2-trichlorotrifluoroethane (C 2 F 3 Cl 3 ) is; At least one undesirable halocarbon impurity is trichloromonofluoromethane (CFCl 3 ) is; At least one undesirable halocarbon impurity is 2,2-dichloro-1,1,1-trifluoroethane (C 2 HF 3 Cl 2 ) is; At least one undesirable halocarbon impurity contains a halogen having a lower electronegativity than fluoride, such as, for example, Cl, Br, and I, which are C a H b F c X d (wherein a is 1 to 7, b is 0 to 13, c is 0 to 15, and d is 1 to 16), and C o F p X qwherein o is 1-7, p is 0-15, and q is 1-16; At least one undesirable halocarbon impurity contains a halogen having a lower electronegativity than fluoride, such as, for example, Cl, Br, and I, which are C a F c X d (wherein a is 1 to 7, c is 0 to 15, and d is 1 to 16) and C o H p F q X r wherein o is 1-7, p is 0-13, q is 0-15, and r is 1-16; Fluorocarbons or hydrofluorocarbons are fluorocarbon and hydrofluorocarbon etching gases; Fluorocarbon and hydrofluorocarbon etching gases include, but are not limited to, CF 4 , CHF 3 , C.H. 2 F 2 , C.H. 3 F, C 2 F 6 , C 2 HF 5 , C 3 HF 5 , C 3 H 2 F 4 , C 3 H 2 F 6 , C 3 F 8 , C 3 F 6 , C 4 F 8 , C 4 F 6 , C 4 H 2 F 4 , C 4 H 2 F 6 , C 5 F 8 , C 5 HF 7 , C6 F 6 Additional examples of fluorocarbon and hydrofluorocarbon gases include, but are not limited to, C 2 H 3 F 3 , C 2 H 2 F 4 , C 2 H 4 F 2 , C 2 H 4 F 2 , C 2 H 5 F, C 3 H 3 F 5 , C 4 F 10 , C 5 F 12 , C 6 F 14 and C 7 F 16 Examples of isomers of Fluorocarbon and hydrofluorocarbon etching gases are 3 H 2 F 6 , 1,1,1,3,3,3-hexafluoropropane (236fa); Fluorocarbon and hydrofluorocarbon etching gases are 3 H 3 F 5 , 1,1,1,3,3-pentafluoropropane (245fa); Inert atmosphere is N 2 , H 2 , He, Ar, Xe or combinations thereof; · the at least one adsorbent bed is a single adsorbent bed; · At least one of the adsorbent beds is two adsorbent beds placed in parallel; · at least one of the adsorbent beds each includes a plurality of beds in series; · at least one of the adsorbent beds is an elongated bed having dimensions desired to purify and control the impurity concentration in the effluent product; The adsorbent is silica, alumina or a molecular sieve; The metal oxide is CuO or MgO; · The metal oxide is CuO supported on alumina; · In the gas phase, the flow rate of the fluorocarbon or hydrofluorocarbon gas into the adsorbent bed is in the range of 0.5 slm to 500 l / min; · The flow rate of fluorocarbon or hydrofluorocarbon gas into the adsorbent bed in the gas phase ranges from 1 slm to 150 l / min; · The flow rate of the fluorocarbon or hydrofluorocarbon liquid to the adsorbent bed in the liquid phase ranges from 0.1 kg / hr to 100 kg / hr; · The flow rate of fluorocarbon or hydrofluorocarbon liquid varies from 0.1 kg / h to 20 kg / h; The temperature of the adsorbent bed ranges from -50℃ to 150℃; The temperature of the adsorbent bed is in the range of 0℃~50℃; ·pressure · The purity of the purified fluorocarbon or hydrofluorocarbon is >99.9%; The purity of the purified fluorocarbon or hydrofluorocarbon is >99.99%; · The concentration of halocarbon impurities in the hydrofluorocarbon or fluorocarbon feed being refined is less than 5%; · The concentration of halocarbon impurities in the hydrofluorocarbon or fluorocarbon feed being refined is less than 1000 ppm; · The concentration of halocarbon impurities in the hydrofluorocarbon or fluorocarbon feed being refined is less than 500 ppm; · The concentration of halocarbon impurities in the hydrofluorocarbon or fluorocarbon feed being refined is less than 200 ppm; · The concentration of impurities in the purified fluorocarbon or hydrofluorocarbon is <1000 ppm; · The concentration of impurities in the purified fluorocarbon or hydrofluorocarbon is <100 ppm; · The concentration of impurities in the purified fluorocarbon or hydrofluorocarbon is <10 ppm; · The concentration of impurities in the purified fluorocarbon or hydrofluorocarbon is <5 ppm; · The concentration of impurities in the purified fluorocarbon or hydrofluorocarbon is <1 ppm; · The concentration of impurities in the purified fluorocarbon or hydrofluorocarbon is <0.1 ppm; · further comprising the step of regenerating the adsorbent bed by continuously flowing a purge gas through the adsorbent bed at a temperature in the range of 25°C to 1000°C; · further comprising the step of regenerating the adsorbent bed by continuously flowing a purge gas through the adsorbent bed at a temperature in the range of 200°C to 400°C; The pressure involved in the regeneration process is 1 torr~100,000 torr; Purge gas is N 2 , H 2 , He, Ar, Xe, Kr or N 2 , H 2 , He, Ar, Xe and Kr; Purge gas is N 2 is; Purge gas is H 2 is; The purge gas is Ar; The purge gas is Xe; · Purge gas is Kr; · Purge gas is He; Purge gas is H 2 and N 2 is; Purge gas is 0 to 100% N 2 Inside H 2 H with a ratio of 2 and N 2 is; Purge gas must contain more than 3% N 2 Inside H 2 H with a ratio of 2 and N 2is; and Purge gas is N 2 , H 2 , He, Ar, Xe and Kr.

[0020] Disclosed is a system for the purification of fluorocarbons or hydrofluorocarbons containing at least one undesirable halocarbon impurity, the system comprising at least one adsorbent bed comprising a metal oxide supported on an adsorbent in an inert atmosphere, the at least one adsorbent bed adapted and configured to adsorb the at least one undesirable halocarbon impurity through physical and / or chemical adsorption. The system of the present disclosure may include one or more of the following aspects: · further including at least one distillation column adapted and configured to distill at least the outlet stream of the adsorbent bed to obtain a purified fluorocarbon or hydrofluorocarbon; The metal oxide is CuO or MgO; The metal oxide loading percentage ranges from 0.1% to 99%; The metal oxide loading percentage is in the range of 5%-50%; · The adsorbents are silica, alumina and molecular sieves; · The operating temperature of at least one distillation column varies from -50°C to 150°C; · The operating temperature of at least one distillation column varies from -20°C to 100°C; the at least one undesirable halocarbon impurity comprises a chlorofluorocarbon (CFC), a hydrochlorofluorocarbon (HCFC), and a Cl-containing halide, a Br-containing halide, an I-containing halide, or a combination thereof; · the at least one undesirable halocarbon impurity comprises a halocarbon containing a halogen bonded to carbon that is less electronegative than fluorine; At least one undesirable halocarbon impurity, including a halocarbon containing a halogen bonded to carbon that is less electronegative than fluorine, is adsorbed; The halogens having a lower electronegativity than fluorine are Cl, Br and / or I; the at least one undesirable halocarbon impurity comprises a halocarbon containing Cl, Br and / or I bonded to carbon; At least one undesirable halocarbon impurity, including carbon-bonded Cl, Br and / or I-containing halocarbons, is adsorbed; the at least one undesirable halocarbon impurity is a Cl-containing halide, a Br-containing halide, an I-containing halide, or a combination thereof; the at least one undesirable halocarbon impurity is a Cl-containing halocarbon, a Br-containing halocarbon, an I-containing halocarbon, or a combination thereof; · the at least one undesirable halocarbon impurity comprises a chlorofluorocarbon (CFC), a hydrochlorofluorocarbon (HCFC); At least one undesirable halocarbon impurity contains a halogen having a lower electronegativity than fluoride, such as, for example, Cl, Br, and I, which are C a H b F c X d (wherein a is 1 to 7, b is 0 to 13, c is 0 to 15, and d is 1 to 16), and C o F p X q wherein o is 1-7, p is 0-15, and q is 1-16; At least one undesirable halocarbon impurity contains a halogen having a lower electronegativity than fluoride, such as, for example, Cl, Br, and I, which are C a F c X d (wherein a is 1 to 7, c is 0 to 15, and d is 1 to 16) and C o H p F q X rwherein o is 1-7, p is 0-13, q is 0-15, and r is 1-16; Fluorocarbons or hydrofluorocarbons are fluorocarbon and hydrofluorocarbon etching gases; Fluorocarbon and hydrofluorocarbon etching gases include, but are not limited to, CF 4 , CHF 3 , C.H. 2 F 2 , C.H. 3 F, C 2 F 6 , C 2 HF 5 , C 3 HF 5 , C 3 H 2 F 4 , C 3 H 2 F 6 , C 3 F 8 , C 3 F 6 , C 4 F 8 , C 4 F 6 , C 4 H 2 F 4 , C 4 H 2 F 6 , C 5 F 8 , C 5 HF 7 , C 6 F 6 Additional examples of fluorocarbon and hydrofluorocarbon gases include, but are not limited to, C 2 H 3 F 3 , C 2 H 2 F 4 , C 2 H 4 F 2 , C 2 H 4 F 2 , C 2 H 5 F, C3 H 3 F 5 , C 4 F 10 , C 5 F 12 , C 6 F 14 and C 7 F 16 Examples of isomers of Fluorocarbon and hydrofluorocarbon etching gases are 3 H 2 F 6 , 1,1,1,3,3,3-hexafluoropropane (236fa); Fluorocarbon and hydrofluorocarbon etching gases are 3 H 3 F 5 , 1,1,1,3,3-pentafluoropropane (245fa); · the at least one adsorbent bed is a single adsorbent bed; · At least one of the adsorbent beds is two adsorbent beds placed in parallel; · at least one of the adsorbent beds each includes a plurality of beds in series; at least one of the adsorbent beds is an elongated bed having dimensions desired to purify and control the impurity concentration in the effluent product; and The adsorbent is silica, alumina or molecular sieve.

[0021] For a further understanding of the nature and objects of the present invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, in which like elements are given the same or similar reference numerals, and in which: [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 shows a block diagram of an exemplary embodiment of a purification system of the present disclosure. [Diagram 2] FIG. 2 shows a block diagram of another exemplary embodiment of a purification system of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Element Number 102 Supply cylinder 104 Adsorption bed 106 Distillation column 108 Cylinder 110 Pump 112 Distillation column 114 Cylinder 116 Cylinder 120 Adsorption bed Explanation of symbols in the abstract 102 Supply cylinder 104 Adsorption bed 106 Distillation column 108 Cylinder 110 Pump 112 Distillation column 114 Cylinder 116 Cylinder

[0024] A method for selective adsorption of halocarbon impurities containing Cl, Br and I in fluorocarbons (FCs) or hydrofluorocarbons (HFCs) using a metal oxide-supported sorbent is disclosed. More specifically, the disclosed method is a method for purifying fluorocarbons or hydrofluorocarbons and removing undesired impurities. The disclosed purification method removes halocarbon contaminants or impurities containing Cl, Br and / or I, which have lower electronegativity than fluoride, from the fluorocarbons or hydrofluorocarbons. In one embodiment, the halocarbon contaminants or impurities contained in the fluorocarbons or hydrofluorocarbons can be chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs). These halocarbon contaminants or impurities are harmful to the use of hydrofluorocarbons or fluorocarbon gases and are also harmful to safety and the environment (e.g., ozone depletion and global warming). These halocarbon contaminants are difficult to remove using distillation in a relatively simple unit with high yields. Some of these impurities may even be difficult to separate from the hydrofluorocarbons or fluorocarbons by conventional distillation. Therefore, the purification method of the present disclosure can be an economically viable alternative by saving initial costs without sacrificing purification efficiency. The highly purified hydrofluorocarbons or fluorocarbons by the purification method of the present disclosure can be applied in the semiconductor industry, metal cleaning processes, and any related fields.

[0025] The disclosed method includes flowing the fluorocarbon or hydrofluorocarbon gas in need of purification through an adsorbent bed packed with adsorbent-loaded metal oxide beads at a specific flow rate and at a specific temperature to selectively adsorb the undesired impurities through physical and / or chemical adsorption in an inert atmosphere without any moisture contamination to avoid undesired reactions with the produced fluorocarbons. 2 , H 2, He, Ar, Xe or combinations thereof. The use of hydrogen in pure form or in mixture with other above gases to form a purge gas can be very effective in dehydroxylation and preparation for adsorption. This step can be followed by distillation of the outlet stream of the adsorbent bed to obtain purified fluorocarbon or hydrofluorocarbon. This distillation step can remove other impurities that are not affected by adsorption. The purified fluorocarbon or hydrofluorocarbon can be obtained by a step alone or by a flowing step and a distillation step. Here, the adsorbent bed can include one or more adsorbent beds. For example, the adsorbent bed can be two adsorbent beds placed in parallel. In the method of the present disclosure, a small amount of the desired product can also be adsorbed, which can then be removed during a regeneration process for the adsorbent bed. In the method of the present disclosure, important impurities in fluorocarbons or hydrofluorocarbons can be removed in an energy-efficient manner with high yields and high recovery rates.

[0026] In the method of the present disclosure, the undesirable impurities containing halogens Cl, Br and / or I, which have lower electronegativity than fluorine, and which are bonded to carbon, are adsorbed. The rest of the impurities should be relatively less harmful to the application and environment and easy to separate using distillation. Therefore, the undesirable impurities containing halides or halocarbons (i.e., containing Cl, Br and I) in the fluorocarbon or hydrofluorocarbon can be easily removed without reaction of the feed gas with the adsorbent and without loss of yield.

[0027] The purified hydrofluorocarbon has the formula C x H y F z (wherein x is 1 to 7, y is 1 to 13, and z is 1 to 16), while undesirable impurities in the feed gas include halogens having lower electronegativity than fluoride, such as Cl, Br, and I, which are C a H b F c X d(wherein a is 1 to 7, b is 0 to 13, c is 0 to 15, and d is 1 to 16), and C o F p X q wherein o is 1-7, p is 0-15, and q is 1-16.

[0028] The purified fluorocarbon has the formula C x F z (wherein x is 1 to 7 and z is 1 to 16), while undesirable impurities in the feed gas include halogens having lower electronegativity than fluoride, such as Cl, Br, and I, which are represented by C a F c X d (wherein a is 1 to 7, c is 0 to 15, and d is 1 to 16) and C o H p F q X r wherein o is 1-7, p is 0-13, q is 0-15, and r is 1-16.

[0029] The undesirable halocarbon impurity reactions include Cl-containing halocarbons, such as chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), Br-containing halocarbons, I-containing halocarbons, or combinations thereof. The undesirable halocarbon impurities include halocarbons that contain a halogen bonded to carbon that is less electronegative than fluorine, such as, for example, Cl, Br, and / or I, and are adsorbed. The undesirable halocarbon impurities are halocarbons that contain a halogen bonded to carbon that is less electronegative than fluorine, such as, for example, Cl, Br, and / or I, and are adsorbed. The undesirable halocarbon impurities are halocarbons that contain Cl, Br, and / or I, and are adsorbed, and are adsorbed. The undesirable halocarbon impurities include halides containing Cl, Br, and / or I, and are adsorbed, and are adsorbed. The undesirable halocarbon impurities include halides containing Cl, Br, and / or I, and are adsorbed, and are adsorbed. The undesirable halocarbon impurities include halides containing Cl, Br, and / or I, and are adsorbed, and are adsorbed. The undesirable halocarbon impurities are Cl-containing halocarbons, Br-containing halocarbons, I-containing halocarbons, or combinations thereof. The undesirable halocarbon impurities include Cl-containing halocarbons, Br-containing halocarbons, I-containing halocarbons, or combinations thereof. The undesirable halocarbon impurities are Cl-containing halocarbons, Br-containing halocarbons, I-containing halocarbons, or combinations thereof. The undesirable halocarbon impurities are 2-chloro-1,1,1-trifluoroethane (C 2 H 2 F 3 Cl), 2-chloro-1,1,3-trifluoropropene (C 3 H 2 F 3 Cl), 2-chloro-1,1,1,2-tetrafluoropropane (C 2 HF 4 Cl), 2-chloro-1,1,1,3,3-pentafluoro-1-propene (C 3 F 5 Cl), 1,1,2-trichlorotrifluoroethane (C 2 F 3 Cl 3), trichloromonofluoromethane (CFCl 3 ) and 2,2-dichloro-1,1,1-trifluoroethane (C 2 HF 3 Cl 2 ), hydrochlorofluorocarbons (HCFCs), etc.

[0030] Fluorocarbon and hydrofluorocarbon gases are traditionally used in a wide variety of applications including as blowing agents for forming foams and insulation, fire suppression systems and extinguishers, refrigerants, heat transfer media, dielectric gases, chemical industry applications, metal refining, and plasma etching gases primarily for silicon and silicon-containing materials in the semiconductor industry.

[0031] Exemplary fluorocarbon and hydrofluorocarbon etch gases that require purification include, but are not limited to, CF 4 , CHF 3 , C.H. 2 F 2 , C.H. 3 F, C 2 F 6 , C 2 HF 5 , C 3 HF 5 , C 3 H 2 F 4 , C 3 H 2 F 6 , C 3 F 8 , C 3 F 6 , C 4 F 8 , C 4 F 6 , C 4 H 2 F 4 , C 4 H 2 F 6 , C 5 F 8 , C 5 HF 7 , C 6 F 6Additional examples of fluorocarbon and hydrofluorocarbon gases include, but are not limited to, C 2 H 3 F 3 , C 2 H 2 F 4 , C 2 H 4 F 2 , C 2 H 4 F 2 , C 2 H 5 F, C 3 H 3 F 5 , C 4 F 10 , C 5 F 12 , C 6 F 14 and C 7 F 16 Examples of isomers include:

[0032] Here, C 3 H 2 F 6 (chemical name 1,1,1,3,3,3-hexafluoropropane, 236fa) is widely used in a variety of applications, including as a bulking agent and extinguishing agent. 3 H 3 F 5 (chemical name 1,1,1,3,3-pentafluoropropane, 245fa) is widely used as a blowing agent to form closed-cell spray foam insulation.

[0033] The fluorocarbon or hydrofluorocarbon to be purified is fed in liquid or gas form, particularly, but not limited to, at 100 kg / hr or less. However, it is important to note that the residence time between liquid-solid adsorption and gas-solid adsorption can be significantly different. Those skilled in the art will understand that the feed amount and feed phase can be changed based on the production amount, selectivity of the adsorbent, desired yield, bed size and residence time. If the residence time in the liquid phase is longer than the residence time in the gas phase, the recovery rate may be reduced due to unwanted side reactions between the desired hydrofluorocarbon or fluorocarbon and the adsorbent or metal oxide. The selectivity can be adjusted by the metal oxide, its loading rate, type of adsorbent and flow rate. If the feed is relatively pure and the concentration of impurities in the feed is not too high, a gas feed is preferred to improve the yield and recovery of the main product.

[0034] The instability of fluorocarbons or hydrofluorocarbons to metals and metal oxides is a well-known issue and is common information in the Safety Data Sheets (SDS) of these compounds. Part of the adsorbent material in the disclosed method is usually used as a catalyst for defluorination of these compounds at high temperatures for substitution or elimination reactions. However, when the disclosed adsorption process is carried out in a controlled manner, at room temperature, and with ideal residence time, it can be an effective and useful tool to selectively remove undesirable impurities without any by-products.

[0035] FIG. 1 shows a block diagram of an exemplary embodiment of the disclosed purification system according to the present invention. Feed gas containing undesired impurities from a feed cylinder 102 or storage tank (not shown) is fed to an adsorbent bed 104 at a desired temperature and flow rate (see below) that optimizes adsorption capacity and selectivity. The feed cylinder 102 or storage tank (not shown) can be heated to a desired temperature to reach a desired flow rate. The feed gas can be any fluorocarbon or hydrofluorocarbon gas containing halocarbon impurities containing halides (e.g., Cl, Br, and I) that are less electronegative than fluoride. The adsorbent bed 104 is packed with adsorbent-supported metal oxide beads in an inert atmosphere. The adsorbent bed 104 can be any adsorbent-supported metal oxide (silica, alumina, etc.). Preferably, the adsorbent bed 104 contains a metal oxide, such as CuO, MgO, etc., supported on an adsorbent such as silica, alumina, or molecular sieves. In one embodiment, the metal oxide is CuO supported on aluminum. The loading percentage of these metal oxides may vary from 0.1 to 99%. Preferably, the loading percentage of these metal oxides may be from 5% to 50%. The temperature of the adsorbent bed 104 may range from -50°C to 150°C; preferably, the temperature of the adsorbent bed 104 may range from 0°C to 50°C. The flow rate of the fluorocarbon or hydrofluorocarbon gas may vary from 0.5 slm to 500 l / min. For the liquid feed, the flow rate of the fluorocarbon or hydrofluorocarbon liquid may vary from 0.1 kg / hr to 100 kg / hr. Preferably, the flow rate of the fluorocarbon or hydrofluorocarbon gas may vary from 1 slm to 150 slm, and for the liquid feed, the flow rate of the fluorocarbon or hydrofluorocarbon liquid may vary from 0.1 kg / hr to 20 kg / hr. Undesirable halocarbon impurities containing chlorine, bromine or iodine may be removed from the feed fluorocarbon or hydrofluorocarbon gas by the adsorbent bed 104 .

[0036] The output or outlet stream from the adsorbent bed 104 is a mixture of a purified fluorocarbon or hydrofluorocarbon product and a N 2 and CO2 The adsorbent bed 104 contains non-condensable gases such as volatile impurities (FC or HFC) with a boiling point lower than the purified fluorocarbon or hydrofluorocarbon product, and light impurities such as volatile impurities (FC or HFC) with a boiling point higher than the product. The first distillation column 106 can separate the light impurities from the product and heavy impurities. The outlet of the adsorbent bed 104 can include a particle filtration system (not shown). The particle filter can be made of, but is not limited to, stainless steel, nickel, Hastelloy, or PTFE. The particle filter can remove particles with a size greater than approximately 1 nm, but is not limited to such. Commercially available filters include, for example, Entegris Wafergard or Pall Corporation Gaskleen line filters. The output of the adsorbent bed 104 is sent to an additional purification bed containing molecular sieves or silica to remove moisture, and then sent to the first distillation column 106 operated at optimal conditions (see below) to separate the light impurities from the product and heavy impurities from the adsorbent bed 104. The light impurities go to cylinder 108. The product and heavy impurities are discharged from the distillation column 106 and pumped by pump 110 to the distillation column 112. Those skilled in the art will appreciate that a variety of packing materials are used in the distillation column, including but not limited to Heli-Pak, ceramic saddles, Raschig rings, balls (Teflon or glass), wire mesh, and specially constructed packing materials. Since the boiling point of the product is then lower than that of the heavy impurities, the product exits the top of the distillation column 112 and is collected through a condenser (not shown) into cylinder 114 or a storage tank (not shown) and a lecture bottle (not shown) for analysis and packaging. The heavy impurities exit the bottom of the distillation column 112 and are then collected as waste in cylinder 116 or a storage tank (not shown). Depending on the impurities contained in the feed fluorocarbon or hydrofluorocarbon, a series of distillation columns can be applied after the adsorbent bed 104. It is possible to have additional equipment such as additional pumps, flow controllers, valves, pressure transducers, sensors, filters, etc. as is generally known in the art of distillation.

[0037] The operating temperature of the distillation column 106 and the distillation column 112 may vary from -50°C to 150°C. Preferably, the operating temperature of the distillation column 106 and the distillation column 112 may vary from -20°C to 100°C.

[0038] The purity of the purified fluorocarbon or hydrofluorocarbon product can be >99.9% by reducing or completely removing undesirable impurities by distillation followed by adsorption according to the purification adsorption method of the present disclosure. Preferably, the purity of the purified fluorocarbon or hydrofluorocarbon product is >99.99% by reducing or completely removing undesirable impurities by distillation followed by adsorption according to the purification adsorption method of the present disclosure.

[0039] The concentration of halocarbon impurities in the hydrofluorocarbon or fluorocarbon feed to be purified is less than 5. Preferably, the concentration of undesirable impurities in the feed gas may be 1000 ppm. More preferably, the concentration of undesirable impurities in the feed gas may be <500 ppm. Even more preferably, the concentration of undesirable impurities in the feed gas may be <200 ppm.

[0040] The concentration of undesirable impurities in the purified fluorocarbon or hydrofluorocarbon product may be <1000 ppm. Preferably, the concentration of undesirable impurities in the purified fluorocarbon or hydrofluorocarbon product may be <100 ppm. Preferably, the concentration of undesirable impurities in the purified fluorocarbon or hydrofluorocarbon product may be <10 ppm. Preferably, the concentration of undesirable impurities in the purified fluorocarbon or hydrofluorocarbon product may be <5 ppm. More preferably, the concentration of undesirable impurities in the purified fluorocarbon or hydrofluorocarbon product may be <1 ppm. Even more preferably, the concentration of undesirable impurities in the purified fluorocarbon or hydrofluorocarbon product may be <0.1 ppm. The feed and product gases and their impurities may be analyzed using a number of analytical instruments including gas chromatography with detectors such as thermal conductivity detectors (TCD), photoionization detectors (PID), pulsed discharge ionization detectors (PDHID), mass spectrometry (MS), and the like. Other detectors include FTIR, moisture analyzers such as Meeco Iceman, or P 2 O 5 Other analyzers based on the technology as well as cavity ring-down spectrometers (CRDS) may be included. It is understood that each analyzer may detect different impurities at different detection limits. Analyzers may be used to analyze points along the exemplary purification system shown in FIG. 1, including but not limited to the feed cylinder 102, the outlet of the adsorbent bed 104, various positions in the distillation columns 106 and 112, the cylinder 114 and the collection cylinder 116 or storage tank (not shown), and the second adsorbent bed 120 (shown in FIG. 2) in parallel with 104. These analyzers may be used to analyze gas or liquid stream samples from the process directly or in a separate collection vessel. These analyses may be used to change process conditions in the distillation column or to determine the breakthrough point occurring in the adsorbent bed. The breakthrough point is defined as the point at which a portion of the adsorbate begins to pass through the adsorbent bed without being adsorbed.

[0041] The adsorbent bed 104 is heated and the balance is He, N 2 , Ar, Xe, Kr, etc., but more preferably N 2 H is an inert gas 2 The continuous purge gas is regenerated with a continuous purge gas containing H. 2 and N 2 The term regeneration may include a process for initially preparing the adsorbent bed or a process for removing impurities reversibly adsorbed in the adsorbent bed after the bed has been used several times, or after it has reached saturation capacity, or after it has reached equilibrium with the feed stream. The temperature of the adsorbent bed 104 during regeneration may vary from 25° C. to 1000° C. The adsorbent bed may be regenerated in a system as shown in FIG. 2, in which two beds 104 and 120 exist in parallel, as well as in a switching system in which one bed can be regenerated while the other is undergoing purification. Alternatively, the used adsorbent bed may be transferred to another system for regeneration (not shown). Preferably, the temperature of the adsorbent bed during regeneration may vary from 200° C. to 400° C. The regeneration temperature may be selected based on the particular material in the adsorbent bed and the nature of the adsorbed impurities. The N 2 The purge flow is greater than 100 sccm. Preferably, N 2 The purge flow is greater than 500 sccm. It is understood that the gas flow rate during regeneration may vary depending on the size of the adsorbent bed. The pressure of the regeneration process may be from 1 torr to 100,000 torr. One skilled in the art will recognize that the pressure of the regeneration process may be selected depending on the particular impurities to be adsorbed in the adsorbent bed. The purge gas H 2 and N 2 is 0 to 100% N 2 Inside H 2 The ratio of N 2 Inside H 2 Concentrations above about 4% are considered flammable, so N 2 <4% of H 2 However, since the explosion limits depend on the inert gas used, one skilled in the art should be aware of the use of different concentrations of H in the regeneration process.2 may be used.

[0042] Depending on the feed gas quality, adsorbent beds 104 and 120 may comprise multiple beds in series or one elongated bed having dimensions desired to purify and control impurity concentrations in the effluent product. EXAMPLES

[0043] The following non-limiting examples are provided to further illustrate embodiments of the present invention, however, these examples are not intended to be all inclusive, nor are they intended to limit the scope of the invention described herein.

[0044] Example 1 One adsorbent bed was copper oxide CuO (13%) on alumina from Sigma Aldrich (part number: 417971-250G). The other pristine adsorbent bed, unloaded with metal oxide, was activated alumina from Delta adsorbents (part number: Activated Alumina AA400G). The physical dimensions of both the metal oxide loaded and unloaded adsorbents were similar (i.e., 14-28 mesh) and both were analyzed using N 2 It is regenerated at 300° C. under purging, and then adsorbed at a flow rate of 500 sccm for about 5 hours with a residence time of about 46 seconds. 2 H 2 F 3 Cl), trichloromonofluoromethane (CFCl 3 ) and 2-chloro-1,1,1,3,3-pentafluoro-1-propene (C 3 F 5 Hydrofluorocarbon gas C containing CFC impurities including Cl 3 H 2 F 6 (236fa) was flowed in the gas phase through the adsorbent bed at room temperature. After passing through the adsorbent bed packed with CuO, the feed hydrofluorocarbon gas C 3 H 2 F 62-Chloro-1,1,1-trifluoroethane (C 2 H 2 F 3 Cl) was reduced from approximately 42 ppm to <1 ppm, while other impurities in the feed fluorocarbon or hydrofluorocarbon gas, trichloromonofluoromethane (CFCl 3 ) was reduced from approximately 139 ppm to <1 ppm. Similarly, another impurity, 2-chloro-1,1,1,3,3-pentafluoro-1-propene (C 3 F 5 When the same feed gas was passed through a pristine alumina bed with no metal oxide loading, the impurity 2-chloro-1,1,1-trifluoroethane (C 2 H 2 F 3 Cl), trichloromonofluoromethane (CFCl 3 ) were reduced to 23 ppm and 46 ppm, respectively. All impurities were measured using gas chromatography mass spectrometry.

[0045] Example 2 C 3 H 3 F 5 (245fa) gas was flowed in the gas phase through an alumina adsorbent bed packed with CuO at room temperature. One of the impurities, 1,1,2-trichlorotrifluoroethane (C 2 F 3 Cl 3 ) was reduced from 284 ppm to <1 ppm, while 2-chloro-1,1,3-trifluoropropene (C 3 H 2 F 3 The concentration of 2,2-dichloro-1,1,1-trifluoroethane (C 2 HF 3 Cl 2 The concentration of the impurity 2-chloro-1,1,1,2-tetrafluoroethane (C 2 HF4 The concentration of Cl) was reduced from 530 ppm to 45 ppm after a single pass through an adsorbent bed containing copper oxide on packed alumina.

[0046] Example 3 The adsorbent bed is filled with pure N 2 , Pure H 2 Or H 2 and N 2 It can be regenerated with a mixture of pure N 2 and N 2 3.5% of H in (remaining amount) 2 In a study evaluating and comparing the performance of adsorbent beds regenerated with 2-chloro-1,1,1-trifluoroethane (C 2 H 2 F 3 The adsorption capacity for removing impurities is N 2 and H 2 If the mixture regenerates the bed, N 2 It was shown that the increase was >10x (10-fold) compared with N alone. 2 For beds regenerated with only 236fa, the breakthrough point for this impurity in 236fa flowed through the bed at 100 sccm occurred in 45 minutes, whereas for beds regenerated with only 236fa flowed through the bed at 100 sccm, the breakthrough point for this impurity in 236fa flowed through the bed at 100 sccm occurred in 45 minutes. 2 3.5% of H in (remaining amount) 2 The adsorbent bed regenerated by was shown to reach breakthrough after 480 minutes.

[0047] Example 4 During the distillation of 236fa gas using a batch distillation column (4 feet long and 2 inches in diameter) at room temperature and Propak packing, it was observed that some of the chlorine impurities formed azeotropes with 236fa, making purification difficult. In particular, two impurities, 2-chloro-1,1,1-trifluoroethane (C 2 H 2 F 3 Cl) (feed concentration: 29 ppm) and 2-chloro-1,1,1,3,3-pentafluoro-1-propene (C 3 F 5Cl) (feed concentration: 47 ppm) does not separate well throughout the distillation column and can only be reduced to 27 ppm and 42 ppm, respectively.

[0048] Example 5 As in the above example, when the same distillation column was used to purify 245fa gas, the chlorine impurity 1,1,2-trichlorotrifluoroethane (C 2 F 3 Cl 3 ) and 2,2-dichloro-1,1,1-trifluoroethane (C 2 HF 3 Cl 2 ) formed an azeotrope with 245fa, resulting in only minimal separation. For example, 1,1,2-trichlorotrifluoroethane (C 2 F 3 Cl 3 ) was reduced from 110 ppm to 60 ppm, while 2,2-dichloro-1,1,1-trifluoroethane (C 2 HF 3 Cl 2 ) only decreased from 6 ppm and 5 ppm.

[0049] In this specification, reference to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in this specification are not necessarily all referring to the same embodiment, nor are individual or alternative embodiments necessarily mutually exclusive of other embodiments. The same applies to the term "implementation."

[0050] As used herein, the articles "a" and "an" as used in this application and the appended claims should generally be construed to mean "one or more" unless specifically stated otherwise or unless the context clearly indicates a reference to the singular form.

[0051] As used herein, in the text or claims, "about," "approximately," or "approximately" means ±10% of the stated value.

[0052] As used herein, the term "regeneration" can refer to the process of initially preparing an adsorbent bed or the process of removing impurities reversibly adsorbed in an adsorbent bed after the bed has been used a number of times, or after it has reached saturation capacity, or after it has reached equilibrium with a feed stream.

[0053] Standard abbreviations for elements from the Periodic Table of the Elements are used herein. It should be understood that elements may be referred to by these abbreviations (e.g., F refers to fluoride, H refers to hydrogen, C refers to carbon, etc.).

[0054] Unique CAS Registry Numbers assigned by the Chemical Abstract Service (or "CAS") are provided to identify the particular molecules disclosed.

[0055] As used herein, the term "hydrocarbon" refers to a saturated or unsaturated functional group containing only carbon and hydrogen atoms. As used herein, the term "alkyl group" refers to a saturated functional group containing only carbon and hydrogen atoms. An alkyl group is a type of hydrocarbon. Furthermore, the term "alkyl group" refers to a straight-chain, branched, or cyclic alkyl group. Examples of straight-chain alkyl groups include, but are not limited to, methyl, ethyl, propyl, butyl, and the like. Examples of branched alkyl groups include, but are not limited to, t-butyl. Examples of cyclic alkyl groups include, but are not limited to, cyclopropyl, cyclopentyl, cyclohexyl, and the like.

[0056] As used herein, the word "exemplary" is used herein to serve as an example, instance, or illustration. Any aspect or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects or designs. Rather, use of the word exemplary is intended to present concepts in a concrete form.

[0057] Furthermore, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or." That is, unless otherwise specified or clear from the context, "X employs A or B" is intended to mean any of the natural inclusive permutations. That is, "X employs A or B" is satisfied in any of the foregoing cases if X employs A; if X employs B; or if X employs both A and B.

[0058] The term "comprising" in the claims is an open transitional phrase meaning that the claim elements identified thereafter are a non-exclusive enumeration, i.e., others may be additionally included and remain within the scope of "comprising." "Comprising" is defined herein to necessarily include the more restrictive transitional phrases "consisting essentially of" and "consisting of," and thus "comprising" may be replaced by "consisting essentially of" or "consisting of" and remain within the scope of "comprising" expressly defined.

[0059] "Providing" in the claims is defined to mean providing, supplying, making available, or preparing something. In the absence of express language to the contrary in the claims, a step may be performed by any actor.

[0060] Ranges may be expressed herein as from about one particular value and / or to about another particular value. When such a range is described, it is to be understood that other embodiments include all combinations within said ranges, as well as from the one particular value and / or to the other particular value. Any and all ranges described herein include their endpoints (i.e., x=1-4 or a range where x is 1-4 includes x=1, x=4, and x=any number therebetween), regardless of whether the term "inclusive" is used.

[0061] As used herein, the term "independently," when used in connection with describing an R group, should be understood to indicate that the R group in question is not only independently selected from other R groups having the same or different subscripts or superscripts, but is also independently selected from any additional species of the same R group. For example, the formula MR 1 x (NR 2 R 3 ) (4-x) (wherein x is 2 or 3), wherein two or three R 1 The groups may be either mutually or R 2 Or R 3 Additionally, unless specifically stated otherwise, the values ​​of R groups should be understood to be independent of each other when used in different formulas.

[0062] As used in this application, the word "exemplary" is used herein to serve as an example, instance, or illustration. Any aspect or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects or designs. Rather, use of the word exemplary is intended to present concepts in a concrete form.

[0063] Although the subject matter described herein may be described in conjunction with example implementations for processing one or more computing application functions / operations of a computing application having a user-interactive component, the subject matter is not specifically limited to these particular embodiments. Rather, the techniques described herein may be applied to any suitable type of user-interactive component execution management method, system, platform and / or apparatus.

[0064] It will be understood that many additional changes in the details, materials, steps and arrangements of parts described and illustrated herein to explain the nature of the invention may be made by those skilled in the art within the principles and scope of the invention as set forth in the appended claims. Accordingly, the invention is not intended to be limited to the specific embodiments in the examples given above and / or in the accompanying drawings.

[0065] Although embodiments of the present invention have been shown and described, modifications thereof may be made by those skilled in the art without departing from the spirit or teachings of the present invention. The embodiments described herein are illustrative only and are not limiting. Many variations and modifications of the compositions and methods are possible and are within the scope of the present invention. Thus, the scope of protection is not specifically limited to the embodiments described herein, but is limited only by the scope of the following claims, which are intended to include all equivalents of the subject matter of the claims.

Claims

1. 1. A process for the purification of fluorocarbons or hydrofluorocarbons containing at least one undesirable halocarbon impurity, comprising the steps of: flowing the fluorocarbon or hydrofluorocarbon through at least one adsorbent bed to selectively adsorb the at least one undesirable halocarbon impurity through physical adsorption and / or chemical adsorption; the at least one adsorbent bed comprises a metal oxide, CuO, supported on an adsorbent in an inert atmosphere; The process wherein said at least one adsorbent bed is regenerated with a purge gas comprising pure H2 or H2 and an inert gas selected from He, N2, Ar, Xe or Kr.

2. 10. The process of claim 1, further comprising distilling the outlet stream of the at least one adsorbent bed to obtain a purified fluorocarbon or hydrofluorocarbon.

3. 2. The process of claim 1, wherein the at least one undesirable halocarbon impurity is a Cl-containing halocarbon, a Br-containing halocarbon, an I-containing halocarbon, or a combination thereof.

4. 2. The process of claim 1, wherein the adsorbent is silica, alumina or a molecular sieve.

5. 2. The process of claim 1, wherein the temperature of the adsorbent bed ranges from -50°C to 150°C.

6. 6. The process of any one of claims 1 to 5, wherein the concentration of impurities in the purified fluorocarbon or hydrofluorocarbon is <1000 ppm.

7. 1. A system for the purification of fluorocarbons or hydrofluorocarbons containing at least one undesirable halocarbon impurity, comprising: at least one adsorbent bed comprising a metal oxide supported on an adsorbent, CuO, in an inert atmosphere, the at least one adsorbent bed adapted and configured to adsorb the at least one undesirable halocarbon impurity through physical adsorption and / or chemical adsorption; The at least one adsorbent bed is regenerated with a purge gas comprising pure H2 or H2 and an inert gas selected from He, N2, Ar, Xe, or Kr; A system that

8. 10. The system of claim 7, further comprising at least one distillation column adapted and configured to distill the outlet stream of the at least one adsorbent bed to obtain a purified fluorocarbon or hydrofluorocarbon.

9. The system according to claim 7 or 8, wherein the metal oxide loading is in the range of 0.1 to 99%.

10. 9. The system of claim 7 or 8, wherein the adsorbents are silica, alumina and molecular sieves.

11. 9. The system of claim 7 or 8, wherein the at least one undesirable halocarbon impurity is a Cl-containing halocarbon, a Br-containing halocarbon, an I-containing halocarbon, or a combination thereof.

12. 1. A process for the purification of a fluorocarbon or hydrofluorocarbon containing at least one undesirable halocarbon impurity, comprising the steps of: flowing said fluorocarbon or hydrofluorocarbon through at least one adsorbent bed to selectively adsorb said at least one undesirable halocarbon impurity through physical and / or chemical adsorption; the at least one adsorbent bed comprises a metal oxide, CuO, supported on an adsorbent in an inert atmosphere; regenerating the at least one adsorbent bed with a purge gas comprising pure H2 or H2 and an inert gas selected from He, N2, Ar, Xe, or Kr; distilling the outlet stream of the at least one adsorbent bed to obtain a purified fluorocarbon or hydrofluorocarbon; A process including.

13. 13. The process of claim 12, wherein the concentration of impurities in the purified fluorocarbon or hydrofluorocarbon is <1000 ppm.

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