Sulfamyl fluoride composition and process for preparing sulfamyl fluoride composition

Abstract

A process for producing a sulfamyl fluoride composition includes providing a solution containing fluorosulfonic acid, urea, and a solvent, reacting the solution at a reaction temperature of 80° C. to about 170° C. to produce a mixture containing sulfamyl fluoride, bis(fluorosulfonyl)imide, ammonium fluorosulfate, and the solvent, separating the ammonium fluorosulfate from the mixture, and separating the mixture into a sulfamyl fluoride composition and a recycle composition, the sulfamyl fluoride composition comprising a higher concentration of sulfamyl fluoride and bis(fluorosulfonyl)imide than the recycle composition. The molar ratio of fluorosulfonic acid to urea in the solution is about 1.80:1 to about 2.00:1.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims priority to U.S. Patent Application No. 17 / 582,562, filed Jan. 24, 2022, which claims the benefit of U.S. Patent Application No. 63 / 143,102, filed Jan. 29, 2021, both of which are hereby incorporated by reference in their entirety.

[0002] The present disclosure relates to sulfamoyl fluoride compositions and processes for producing sulfamoyl fluoride compositions.

Background Art

[0003] Sulfamoyl fluoride (H2NSO2F) is a strong acid useful in many applications, including as a raw material in the production of lithium sulfamoyl fluoride, which may be useful in lithium - ion batteries.

[0004] Bis(fluorosulfonyl)imide (HFSI) is an important raw material in the production of lithium bis(fluorosulfonyl)imide (LiFSI) used in lithium - ion batteries. HFSI can be prepared by several methods.

[0005] U.S. Patent No. 8,337,797 to Honda et al. discloses that HFSI can be prepared by the reaction of urea, shown in Formula 1, with fluorosulfonic acid. Formula 1: 5HSO3F + 2CO(NH2)2 → HN(SO2F)2 + 2CO2 + 3NH4SO3F.

[0006] Honda discloses a two-step batch process for producing HFSI from urea and fluorosulfonic acid. In the first step, urea is dissolved in fluorosulfonic acid at a temperature low enough to prevent the reaction of formula 1 between urea and fluorosulfonic acid. In the second step, the urea / fluorosulfonic acid solution is slowly added to separate reaction vessels containing a reaction medium heated sufficiently for the reaction of formula 1 to proceed. Controlled addition allows for control of the heat generated by the exothermic reaction of formula 1. U.S. Patent No. 8,337,797 discloses that the heated reaction medium can be fluorosulfonic acid or HFSI, but it is preferable to use a mixture of fluorosulfonic acid and HFSI, as HFSI helps to further control the reaction, especially at the start, when the urea / fluorosulfonic acid solution is first added to the heated reaction medium. However, the batch process disclosed in U.S. Patent No. 8,337,797 is not sufficient to produce HFSI on an efficient commercial scale.

[0007] Honda et al.'s International Publication No. 2011 / 111780 further discloses a recovery process for continuously removing the reaction mixture from the reaction vessel, including a thorough overflow outlet, and for continuously discharging the reaction mixture in a slurry state (including ammonium salt byproducts). The disclosed process is carried out in product batches, and the product HFSI is added back into the reaction vessel before the reaction of the next product batch.

[0008] Therefore, it is necessary to develop an efficient process that can be scaled up to produce commercial quantities of sulfamyl fluoride, and an even more efficient process that can be scaled up to produce commercial quantities of HFSI. [Overview of the Initiative]

[0009] This disclosure provides a sulfamyl fluoride composition, a process for producing a sulfamyl fluoride composition, and a process for producing HFSI from a sulfamyl fluoride composition.

[0010] In one embodiment, the present invention provides a process for producing a sulfamyl fluoride composition. The process includes providing a solution comprising fluorosulfonic acid, urea, and a solvent, wherein the molar ratio of fluorosulfonic acid to urea is about 1.80:1 to about 2.00:1; reacting the solution at a reaction temperature of 80°C to about 170°C to produce a mixture comprising sulfamyl fluoride, bis(fluorosulfonyl)imide, ammonium fluorosulfate, and a solvent; separating ammonium fluorosulfate from the mixture; and separating the mixture into a sulfamyl fluoride composition and a recycled composition, wherein the sulfamyl fluoride composition contains higher concentrations of sulfamyl fluoride and bis(fluorosulfonyl)imide than the recycled composition.

[0011] In another embodiment, the present invention provides a composition comprising sulfamyl fluoride and bis(fluorosulfonyl)imide, wherein the concentration of sulfamyl fluoride is about 1 mole percent to about 10 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide.

[0012] In another embodiment, the present invention provides a composition comprising sulfamyl fluoride and bis(fluorosulfonyl)imide, wherein the concentration of sulfamyl fluoride is about 50% to about 99.9% by weight of the composition.

[0013] By considering the attached drawings and referring to the following description of embodiments, the above and other features of this disclosure, as well as the ways in which they are achieved, will become clearer and better understood. [Brief explanation of the drawing]

[0014] [Figure 1] This is a process flow diagram showing an integrated process for the continuous production of sulfamyl fluoride compositions according to some embodiments of the present disclosure. [Figure 2]This is a process flow diagram illustrating an integrated process for the continuous production of bis(fluorosulfonyl)imide from a sulfamyl fluoride composition according to some embodiments of the present disclosure. [Figure 3] This is a graph of sulfamyl fluoride concentration as a function of the ratio of fluorosulfonic acid to urea. [Modes for carrying out the invention]

[0015] This disclosure provides an integrated process that can be scaled up to produce commercially viable amounts of sulfamyl fluoride composition from the reaction of fluorosulfonic acid and urea. Surprisingly, it has been found that the process yield can be dramatically improved by limiting the ratio of fluorosulfonic acid to urea.

[0016] The disclosure further provides an integrated process that can be scaled up to produce commercial quantities of bis(fluorosulfonyl)imide from a sulfamyl fluoride composition. In some embodiments, the process includes recycling unreacted fluorosulfonic acid in an efficient and continuous manner. Alternatively or additionally, in some embodiments, the process includes directing the recycled unreacted fluorosulfonic acid to a storage tank.

[0017] As disclosed herein, sulfamyl fluoride is produced from a solution comprising urea, fluorosulfonic acid, and a solvent. Surprisingly, it has been found that at a fluorosulfonic acid to urea molar ratio of 2.0:1, sulfamyl fluoride can be produced with bis(fluorosulfonyl)imide at a concentration exceeding 3 mol percent of the sulfamyl fluoride-bis(fluorosulfonyl)imide combination. At a fluorosulfonic acid to urea molar ratio of 1.9:1, sulfamyl fluoride can be produced with bis(fluorosulfonyl)imide at a concentration exceeding 7 mol percent of the sulfamyl fluoride-bis(fluorosulfonyl)imide combination. In contrast, at a fluorosulfonic acid to urea molar ratio of 2.5:1, sulfamyl fluoride is produced at a concentration of less than 0.5 mol percent, and at fluorosulfonic acid to urea molar ratios of 3.0:1 or higher, sulfamyl fluoride is produced at less than 0.1 mol percent (see the following examples).

[0018] However, the solubility limit of urea in fluorosulfonic acid is approximately 1 mole of urea per 2.5 moles of fluorosulfonic acid, or a molar ratio of fluorosulfonic acid to urea of ​​approximately 2.5:1. Therefore, a compatible solvent is required to maintain urea in the solution at a desired molar ratio of fluorosulfonic acid to urea of ​​2.0:1 or less. Examples of compatible solvents include bis(fluorosulfonyl)imide, sulfolane, and dimethylformamide.

[0019] The molar ratio of fluorosulfonic acid to urea in a solution of urea, fluorosulfonic acid, and a solvent is defined as being low, for example, about 1.80:1, about 1.82:1, about 1.84:1, about 1.86:1, about 1.88:1, or about 1.90:1, or high, for example, about 1.92:1, about 1.94:1, about 1.96:1, about 1.98:1, or about 2.00:1, or between any two of the aforementioned values. The molar ratio of fluorosulfonic acid to urea in the solution may be within any range, for example, about 1.80:1 to about 2.00:1, about 1.82:1 to about 1.98:1, about 1.84:1 to about 1.96:1, about 1.86:1 to about 1.94:1, about 1.88:1 to about 1.92:1, about 1.80:1 to about 1.98:1, about 1.80:1 to about 1.96:1, about 1.80:1 to about 1.94:1, about 1.80 to about 1.88, or about 1.92:1 to about 1.98:1. Preferably, the molar ratio of fluorosulfonic acid to urea in the solution is about 1.80 to about 1.98:1. More preferably, the molar ratio of fluorosulfonic acid to urea in the solution is about 1.82:1 to about 1.96:1. Most preferably, the molar ratio of fluorosulfonic acid to urea in the solution is about 1.84:1 to about 1.94:1.

[0020] In some embodiments, a solution of urea and fluorosulfonic acid may be formed by mixing urea and the solvent together until the urea is dissolved, and then adding the urea / solvent solution to the fluorosulfonic acid. The urea and fluorosulfonic acid are thought to react according to Formula 2. Formula 2 2HSO3F+CO(NH2)2→H2NSO2F+CO2+NH4SO3F.

[0021] In the reaction shown in Equation 2, urea (CO(NH2)2) and fluorosulfonic acid (HSO3F) react to form sulfamyl fluoride (H2NSO2F) together with the by-products carbon dioxide (CO2) and ammonium fluorosulfate (NH4SO3F).

[0022] The reaction temperature for the reaction of Formula 2 can be low, such as about 80 °C, about 90 °C, about 100 °C, about 110 °C, or about 120 °C, or high, such as about 130 °C, about 140 °C, about 150 °C, about 160 °C, or about 170 °C, or within any range defined between any two of the aforementioned values, for example, about 80 °C to about 170 °C, about 90 °C to about 160 °C, about 100 °C to about 150 °C, about 110 °C to about 140 °C, about 120 °C to about 130 °C, about 130 °C to about 150 °C, or about 110 °C to about 120 °C. Preferably, the reaction temperature is about 110 °C to about 140 °C. More preferably, the reaction temperature is about 120 °C to about 140 °C. Most preferably, the reaction temperature is about 120 °C to about 130 °C.

[0023] The amount of urea available is greater than the stoichiometric amount according to Formula 2, and the availability of fluorosulfonic acid for the side reactions described below is limited. In some embodiments, unreacted urea precipitates with ammonium fluorosulfate. In some embodiments, when the conditions are acidic and the temperature exceeds about 130 °C, unreacted urea decomposes to produce ammonia and carbon dioxide. Ammonia can react with fluorosulfonic acid to produce ammonium fluorosulfate.

[0024] Two side reactions that consume the desired sulfamoyl fluoride can also occur. In one of the sulfamoyl fluoride consumption reactions, sulfamoyl fluoride reacts with the available fluorosulfonic acid to form bis(fluorosulfonyl)imide along with the by-products carbon dioxide, ammonium fluorosulfate, and water according to Formula 3. Formula 3 HSO3F + H2NSO2F → HN(SO2F)2 + H2O.

[0025] Evidence for the reaction schemes of Formulas 2 and 3 was found by monitoring the level of sulfamyl fluoride in response to the alternating addition of urea and fluorosulfonic acid. It was found that the addition of urea increased the concentration of sulfamyl fluoride, and the addition of fluorosulfonic acid decreased the concentration of sulfamyl fluoride. Without wishing to be bound by any theory, by limiting the available fluorosulfonic acid (by limiting the ratio of fluorosulfonic acid to urea), more fluorosulfonic acid is consumed in the reaction of Formula 2 and less fluorosulfonic acid is consumed in the reaction of Formula 3, and thus it is believed that the amount of sulfamyl fluoride consumed to form bis(fluorosulfonyl)imide is reduced. In this way, the concentration of sulfamyl fluoride in the resulting composition can be increased to a level suitable for further commercial use, such as the production of additional bis(fluorosulfonyl)imide, or the separation from bis(fluorosulfonyl)imide to produce a sulfamyl fluoride composition.

[0026] In another of the sulfamyl fluoride consumption reactions, sulfamyl fluoride reacts with the water produced in Formula 3 to form additional ammonium fluorosulfate according to Formula 4. Formula 4 H2O + H2NSO2F → NH4SO3F.

[0027] Limiting the water available for the reaction of Formula 4 can be achieved, as described above, by limiting the reaction of Formula 3. Additionally or alternatively, the water available for the reaction of Formula 4 can be limited by removing water from the mixture. For example, in some embodiments, a stream of dry inert gas, such as nitrogen or carbon dioxide, can be bubbled through the mixture, carrying away water from the mixture.

[0028] The mixture produced by the reaction of equation 2 comprises sulfamyl fluoride, ammonium fluorosulfate, and a solvent. Since the reaction of equation 3 is not completely suppressed, and some of the sulfamyl fluoride produced by the reaction of equation 2 may react with some of the fluorosulfonic acid not yet consumed by the reaction of equation 2, the mixture may also contain bis(fluorosulfonyl)imide. If there is insufficient solvent to dissolve the resulting ammonium fluorosulfate, the mixture may be in the form of a slurry. Alternatively, the mixture may be in the form of a solution.

[0029] In some embodiments, the weight ratio of solvent to urea and fluorosulfonic acid is high enough to completely dissolve the reaction byproducts, including ammonium fluorosulfate, in the mixture, thus avoiding the need to process the slurry. However, increasing the amount of solvent reduces the efficiency of the process to the extent that a larger system and increased energy consumption are required to separate the sulfamyl composition from the solvent. Therefore, in some embodiments, it is desirable to use a lower weight ratio of solvent to urea and fluorosulfonic acid, resulting in the formation of a slurry containing undissolved ammonium fluorosulfate.

[0030] The generated carbon dioxide gas can be aerated or captured for other uses. The generated water contains residual acid and can therefore be separated and neutralized.

[0031] Ammonium fluorosulfate is separated from the mixture. Ammonium fluorosulfate can be separated, for example, by evaporation, spray drying, filtration, or any combination thereof.

[0032] After ammonium fluorosulfate is separated from the mixture, the mixture is separated into a sulfamyl fluoride composition and a recycled composition. The sulfamyl fluoride composition contains a higher concentration of sulfamyl fluoride than the recycled composition. In some embodiments, the recycled composition is recycled back into the reaction. In some embodiments, the recycled composition may be directed to a storage tank for later use, either alternatively or additionally. Separation may be by distillation, for example.

[0033] It has been found that the concentration of sulfamyl fluoride in the sulfamyl fluoride composition may be as low as, for example, about 1 mole percent (mol%), about 2 mol%, about 3 mol%, about 4 mol%, or about 5 mol%, or as high as, for example, about 6 mol%, about 7 mol%, about 8 mol%, about 9 mol%, or about 10 mol%, or within any range defined between any two of the aforementioned values, for example, about 1 mol% to about 10 mol%, about 2 mol% to about 9 mol%, about 3 mol% to about 8 mol%, about 4 mol% to about 7 mol%, about 5 mol% to about 6 mol%, about 5 mol% to about 8 mol%, about 2 mol% to about 5 mol%, or about 6 mol% to about 10 mol%. Preferably, the concentration of sulfamyl fluoride in the sulfamyl fluoride composition is about 2 mol% to about 9 mol%. More preferably, the concentration of sulfamyl fluoride in the sulfamyl fluoride composition is about 3 mol% to about 8 mol%. Most preferably, the concentration of sulfamyl fluoride in the sulfamyl fluoride composition is about 4 mol% to about 8 mol%. The concentration of sulfamyl fluoride in the sulfamyl fluoride composition is the mol% of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide.

[0034] In some embodiments, sulfamyl fluoride may be separated from the sulfamyl fluoride composition to form a concentrated sulfamyl fluoride composition. The separation may be carried out, for example, by distillation. The concentrated sulfamyl fluoride composition may be used, for example, to produce an electrolyte for lithium batteries.

[0035] The concentration of sulfamyl fluoride in the concentrated sulfamyl fluoride composition may be as low as, for example, about 50% by weight (weight %), about 60% by weight, about 70% by weight, about 80% by weight, or about 90% by weight, or as high as about 95% by weight, about 97% by weight, about 98% by weight, about 99% by weight, about 99.5% by weight, or about 99.9% by weight, or within any range defined between any two of the aforementioned values, for example, about 50% by weight to about 99.9% by weight, about 60% by weight to about 99.5% by weight, about 70% by weight to about 99% by weight, about 80% by weight to about 98% by weight, about 90% by weight to about 97% by weight, about 50% by weight to about 70% by weight, about 98% by weight to about 99.9% by weight, or about 99.5% by weight to about 99.9% by weight. Preferably, the concentration of sulfamyl fluoride in the sulfamyl fluoride composition is about 90% to about 99.9% by weight. More preferably, the concentration of sulfamyl fluoride in the sulfamyl fluoride composition is about 95% to about 99.9% by weight. Most preferably, the concentration of sulfamyl fluoride in the sulfamyl fluoride composition is about 99.5% to about 99.9% by weight. The concentration of sulfamyl fluoride in the concentrated sulfamyl fluoride composition is the weight percentage of the concentrated sulfamyl fluoride composition.

[0036] Sulfamyl fluoride compositions and / or concentrated sulfamyl fluoride compositions can be used to produce bis(fluorosulfonyl)imide (HFSI) by using the reaction of Formula 3 as the first reaction. Sulfamyl fluoride compositions and / or concentrated sulfamyl fluoride compositions can be mixed and reacted with additional fluorosulfonic acid in a reactor to form a crude HFSI product composition and a volatile composition. The volatile composition can be removed by operating the reactor under vacuum (vacuum reactor) and / or by flowing a carrier gas such as nitrogen or argon through the reactor. The volatile composition contains unreacted fluorosulfonic acid and water. The crude HFSI product composition contains bis(fluorosulfonyl)imide, ammonium fluorosulfate, unreacted fluorosulfonic acid, and unreacted sulfamyl fluoride.

[0037] The reaction temperature for reacting sulfamyl fluoride in a sulfamyl fluoride composition with fluorosulfonic acid may be as low as, for example, about 80°C, about 90°C, about 100°C, about 110°C, or about 120°C, or as high as, for example, about 130°C, about 140°C, about 150°C, about 160°C, or about 170°C, or within any range defined between any two of the aforementioned values, for example, about 80°C to about 170°C, about 90°C to about 160°C, about 100°C to about 150°C, about 110°C to about 140°C, about 120°C to about 130°C, about 130°C to about 150°C, or about 110°C to about 120°C. Preferably, the reaction temperature is about 110°C to about 140°C. More preferably, the reaction temperature is about 120°C to about 140°C. Most preferably, the reaction temperature is about 120°C to about 130°C.

[0038] The reaction pressure for reacting sulfamyl fluoride with fluorosulfonic acid in the sulfamyl fluoride composition is less than 1 bar absolute pressure to remove the volatile composition containing water. As shown in Formula 4 above, water can react with a portion of the sulfamyl fluoride to produce ammonium fluorosulfate instead of bis(fluorosulfonyl)imide, so removing water can increase the yield of bis(fluorosulfonyl)imide. By removing water, the consumption of this sulfamyl fluoride is reduced, increasing the yield of bis(fluorosulfonyl)imide from sulfamyl fluoride.

[0039] Therefore, by dividing the production of bis(fluorosulfonyl)imide into two steps, namely a first step of preparing a sulfamyl fluoride composition and / or a concentrated sulfamyl fluoride composition, and a second step of reacting the sulfamyl fluoride in the sulfamyl fluoride composition with fluorosulfonic acid and removing water, the amount of ammonium fluorosulfate produced overall can be reduced, improving the overall yield and efficiency of the process.

[0040] The crude HFSI product composition contains bis(fluorosulfonyl)imide, ammonium fluorosulfate, some unreacted fluorosulfonic acid, and some unreacted sulfamyl fluoride. Because the fluorosulfonic acid is in stoichiometric excess, as the reaction proceeds until it is mostly complete, very little sulfamyl fluoride remains in the crude HFSI product composition.

[0041] The concentration of sulfamyl fluoride in the crude HFSI product composition may be less than about 0.5 mol%, less than about 0.4 mol%, less than about 0.3 mol%, less than about 0.2 mol%, or less than about 0.1 mol%, or within any range defined between any two of the aforementioned values.

[0042] Ammonium fluorosulfate is separated from the crude HFSI product composition to form the HFSI product composition. Ammonium fluorosulfate can be separated, for example, by evaporation, spray drying, filtration, or any combination thereof.

[0043] After separating ammonium fluorosulfate from the crude HFSI product composition, the resulting HFSI product composition is separated into a concentrated HFSI product composition and a top stream composition. The concentrated HFSI product composition contains a higher concentration of bis(fluorosulfonyl)imide than the top stream composition. The top stream composition contains water and unreacted fluorosulfonic acid. Separation may be performed, for example, by distillation.

[0044] In some embodiments, the top stream is separated into an aqueous composition and an FSA-rich composition. The FSA-rich composition contains a higher concentration of fluorosulfonic acid than the aqueous composition. In some embodiments, the FSA-rich composition is recycled back into the reactor. In some embodiments, the FSA-rich composition may be directed to a storage tank for later use, either alternatively or additionally. Separation may be by, for example, distillation.

[0045] In some embodiments, the volatile composition is separated into a condensed stream and an uncondensed stream. The condensed stream contains the majority of the unreacted fluorosulfonic acid in the volatile composition. The condensed stream can be recycled back into the reactor. The uncondensed stream contains water and the remainder of the unreacted fluorosulfonic acid in the volatile composition. The uncondensed stream can be separated into an aqueous composition and an FSA-rich composition. The FSA-rich composition contains a higher concentration of fluorosulfonic acid than the aqueous composition. In some embodiments, the FSA-rich composition is recycled back into the reactor. In some embodiments, the FSA-rich composition can be directed to a storage tank for later use, either alternatively or additionally. Separation may be by, for example, distillation.

[0046] In some embodiments, the separation of the uncondensed stream into aqueous and FSA-rich compositions may be carried out using the same separation system as the separation of the top stream into aqueous and FSA-rich compositions. In other embodiments, these separation steps are carried out in their own separate separation systems.

[0047] In some embodiments, the process described above is a continuous process. In some other embodiments, the process described above is a semi-batch process. A semi-batch process means that a significant portion of the process is continuous, but the entire process is not continuous. For example, in some semi-batch embodiments, a sulfamyl fluoride composition can be produced and stored continuously over a period of time, and then the stored sulfamyl fluoride composition can be used to continuously produce bis(fluorosulfonyl)imides.

[0048] Figure 1 is a process flow diagram showing an integrated process for the continuous production of sulfamyl fluoride compositions according to several embodiments of the present disclosure. Figure 1 shows a system 10 including a container 12 configured to be connected to a urea inlet 14 and a solvent inlet 16. The solvent in the solvent inlet 16 is in liquid form and can be continuously pumped into the container 12. Alternatively, the solvent in the solvent inlet 16 can be added in batches. The urea in the urea inlet 14 is in solid form and can be continuously supplied to the container 12 by, for example, a solid transport system (not shown). Alternatively, the urea in the urea inlet 14 can be added to the container 12 in batches.

[0049] The container 12 includes, for example, a mixing device 18 such as a stirrer, and an optional heating and cooling mechanism (not shown) such as a heat transfer coil. In the container 12, urea from the urea input stream 14 and solvent from the solvent input stream 16 are mixed by the mixing device 18.

[0050] Reactor 20 is fluidly connected to container 12 to receive a urea solution 22 containing urea and solvent from container 12. Reactor 20 includes a first fluorosulfonic acid inlet 24 for supplying fluorosulfonic acid to reactor 20. The fluorosulfonic acid and urea solution form a solution containing fluorosulfonic acid, urea, and solvent in the reactor. The molar ratio of fluorosulfonic acid to urea is as described above. Reactor 20 may also include an inert gas inlet 25 for supplying a dry inert gas to cause foaming through the solution. Reactor 20 is heated to the reaction temperature as described above, and the reactants react according to formula 2 to produce a mixture 26 containing sulfamyl fluoride, bis(fluorosulfonyl)imide, ammonium fluorosulfate, and solvent. Carbon dioxide produced by the reactor can be aerated from reactor 20 through a reactor vent 28. The dry inert gas causes foaming through the solution and absorbs water produced by the side reaction of formula 3 described above. The inert gas containing the absorbed water can also be vented out of the reactor through the reactor vent 28. The reactor 20 is configured to maintain the reaction temperature, for example, by a fluid flowing through a heat exchanger or jacketed reactor (not shown), or by an electric heating coil (not shown).

[0051] The first separator 30 is fluidly connected to the reactor 20 to receive a mixture 26 containing sulfamyl fluoride, bis(fluorosulfonyl)imide, ammonium fluorosulfate, unreacted fluorosulfonic acid, and a solvent. The first separator 30 is configured to separate the ammonium fluorosulfate from the mixture 26 to produce a mixture 32. The ammonium fluorosulfate is removed by purging 34. The first separator 30 can be, for example, an evaporator, a spray dryer, a filter, a centrifuge, or any combination thereof.

[0052] A second separator 36 is fluidly connected to the first separator 30 to receive a mixture 32 containing sulfamyl fluoride, bis(fluorosulfonyl)imide, unreacted fluorosulfonic acid, and a solvent. The second separator 36 is configured to produce a sulfamyl fluoride composition 38 and a recycled composition 40. The second separator 36 may be, for example, a distillation column. The sulfamyl fluoride composition 38 contains sulfamyl fluoride at a higher concentration than the concentration of sulfamyl fluoride in the recycled composition 40. The concentration of sulfamyl fluoride in the sulfamyl fluoride composition 38 is as described above.

[0053] The reactor 20 is fluid-connected to a second separator 36 to receive the recycled composition 40. Alternatively, or additionally, the second separator 36 is fluid-connected to a recycled storage tank (not shown). Thus, the recycled composition 40 can be directed to the reactor 20 for continuous operation or to the recycled storage tank for half-batch operation.

[0054] In some embodiments, the sulfamyl fluoride composition 38 may be directed to a product storage tank (not shown) for a later process. In other embodiments, the sulfamyl fluoride composition 38 may be directed to a distillation column (not shown) to produce a concentrated sulfamyl fluoride composition as described above. The concentrated sulfamyl fluoride composition may be used as a precursor for salts for electrolytes in lithium-ion batteries.

[0055] In some embodiments, the sulfamyl fluoride composition 38 (or concentrated sulfamyl fluoride composition) may be used to produce bis(fluorosulfonyl)imide, as shown in Figure 2. Figure 2 is a process flow diagram showing an integrated process for the continuous production of bis(fluorosulfonyl)imide from the sulfamyl fluoride composition and / or concentrated sulfamyl fluoride composition according to some embodiments of the present disclosure. Figure 2 shows a system 42 including a reactor 44 configured to be connected to a source of sulfamyl fluoride composition 38 and a source of additional fluorosulfonic acid 46. The sulfamyl fluoride composition 38 and the additional fluorosulfonic acid 46 form a mixture in the reactor 44. The reactor 44 is heated to the reaction temperature as described above. The reactants react according to Formula 3 to produce the crude HFSI product composition 48 and the volatile composition 50.

[0056] The reactor 44 is configured to maintain the reaction temperature, for example, by a fluid flowing through a heat exchanger or reactor jacket (not shown), or by an electric heating coil (not shown). In some embodiments, the reactor is a vacuum reactor that uses a vacuum to remove the volatile composition 50 from the reactor 44. In some embodiments, a carrier gas such as nitrogen or argon is supplied to the reactor to remove the volatile composition 50 from the reactor 44.

[0057] Crude HFSI product composition 48 contains bis(fluorosulfonyl)imide, ammonium fluorosulfate, unreacted fluorosulfonic acid, and unreacted sulfamyl fluoride. The concentration of unreacted sulfamyl fluoride in crude HFSI product composition 48 is as described above. Volatile composition 50 contains water and unreacted fluorosulfonic acid.

[0058] The condenser 52 is fluidly connected to the reactor 44 to separate the volatile composition 50 into an uncondensed stream 54 and a condensed stream 56. The condensed stream 56 contains the majority of the unreacted fluorosulfonic acid in the volatile composition 50. The condensed stream 56 is fluidly connected to the reactor 44 to return the unreacted fluorosulfonic acid to the reactor 44. The uncondensed stream 54 contains water and the remaining unreacted fluorosulfonic acid.

[0059] A third separator 58 is fluidly connected to the reactor 44 to receive the crude HFSI product composition 48. The third separator 58 is configured to separate ammonium fluorosulfate from the crude HFSI product composition 48 to produce the HFSI product composition 60. The ammonium fluorosulfate is removed by purging 62. The third separator 58 may be, for example, an evaporator, a spray dryer, a filter, a centrifuge, or any combination thereof.

[0060] A fourth separator 64 is fluid-connected to a third separator 56 to receive an HFSI product composition 60 containing bis(fluorosulfonyl)imide, unreacted fluorosulfonic acid, and unreacted sulfamyl fluoride. The fourth separator 64 is also fluid-connected to a condenser 52 to receive an uncondensed stream 54 containing water and some unreacted fluorosulfonic acid. The fourth separator 64 is configured to separate the HFSI product composition 60 into a concentrated HFSI product composition 66 and a top stream 68. The fourth separator 64 may be, for example, a distillation column. The concentrated product composition 66 contains bis(fluorosulfonyl)imide at the concentrations described above. The concentrated product composition 66 may be directed to a product storage tank (not shown) for subsequent processing, purification, or use as an electrolyte for lithium-ion batteries. The top stream 68 contains water and unreacted fluorosulfonic acid.

[0061] A fifth separator 70 is fluidly connected to a fourth separator 64 to receive a top stream 68 containing water and unreacted fluorosulfonic acid from the HFSI product composition 60 and the uncondensed stream 54. The fifth separator 70 is configured to separate the top stream 68 into an aqueous composition 72 and an FSA-rich composition 74. The fifth separator 70 may be, for example, a distillation column. The aqueous composition 72 may contain water produced as shown in Formula 3 and acids produced by other side reactions. The aqueous composition 72 may be sent to a caustic scrubber (not shown) for processing. The FSA-rich composition 74 may contain unreacted fluorosulfonic acid.

[0062] In some embodiments, the condenser 52 is alternatively or additionally directly fluid-connected to a fifth separator 70 to receive an uncondensed stream 54 containing water and a portion of unreacted fluorosulfonic acid. The fifth separator 70 is configured to separate the uncondensed stream 54 together with the top stream 68 into an aqueous composition 72 and an FSA-rich composition 74.

[0063] Reactor 44 is fluid-connected to a fifth separator 70 to receive the FSA-rich composition 74. Alternatively, or additionally, a fifth separator 64 is fluid-connected to a recycle storage tank (not shown). Thus, the FSA-rich composition 74 can be directed to reactor 44 for continuous operation or to the recycle storage tank for semi-batch operation.

[0064] As used herein, the phrase “any range defined between any two of the aforementioned values” means that any range can be selected from any two of the values ​​listed before such phrase, regardless of whether those values ​​are in the lower or higher part of the enumeration. For example, a pair of values ​​can be selected from two lower values, two higher values, or a lower value and a higher value. As used herein, the singular forms “a,” “an,” and “the” include the plural form unless the context explicitly indicates otherwise.

[0065] With regard to the term "inaccurate," the terms "about" and "approximately" may be used interchangeably and refer to measurements including the stated measurement, as well as any measurement that is reasonably close to the stated measurement. A measurement that is reasonably close to the stated measurement deviates from the stated measurement by a reasonably small amount, as can be understood and readily verified by a person skilled in the art. Such deviations may result, for example, from measurement errors or fine-tuning made to optimize performance. If a person skilled in the art determines that the value of such a reasonably small difference cannot be readily verified, the terms "about" and "approximately" may be understood to mean plus or minus 10% of the stated value.

[0066] It should be understood that the foregoing description is merely illustrative of the present disclosure. Various alternative and modified forms can be devised by those skilled in the art without departing from the present disclosure. Accordingly, the present disclosure is intended to encompass all such alternative forms, modifications, and variations that fall within the scope of the appended claims. [Examples]

[0067] Effect of fluorosulfonic acid to urea ratio in the formation of sulfamyl fluoride This example demonstrates the effect of the fluorosulfonic acid to urea ratio on the yield of sulfamyl fluoride in a sulfamyl fluoride composition. Eight experiments were conducted, each using a different ratio of fluorosulfonic acid to urea. For each experiment, a portion of the fluorosulfonic acid and urea were mixed together and then added to a reactor containing the remainder of the fluorosulfonic acid, preheated to 80°C–140°C. The addition typically occurred over approximately 1–2 hours. After the addition was complete, the reaction mixture was maintained at 80°C–140°C for a further 2–3 hours to ensure completion of the reaction. The contents of the reactor were then heated to approximately 160°C and distilled under reduced pressure of 0–10 Torr to separate the generated HFSI and unreacted fluorosulfonic acid from the generated ammonium fluorosulfate. The recovered distillates were analyzed by 19F NMR to determine the molar percentages of HFSI, fluorosulfonic acid, and sulfamyl fluoride. The results are shown in Figure 3.

[0068] Figure 3 is a graph of sulfamyl fluoride concentration for each experiment as a function of the molar ratio of fluorosulfonic acid to urea (FSA:urea). As shown in Figure 3, the sulfamyl fluoride concentration is less than 0.1 mol% at FSA:urea ratios of 3:1 or higher. Even at low FSA:urea ratios such as 2.5:1, the sulfamyl fluoride concentration is less than 0.5 mol%. Once the FSA:urea ratio reaches 2.0:1, the sulfamyl fluoride concentration becomes significant at approximately 3.5 mol%. The sulfamyl fluoride concentration increases dramatically at FSA:urea ratios below 2.0:1, resulting in a sulfamyl fluoride concentration of 7.2 mol% at an FSA:urea ratio of 1.9:1. This surprising result demonstrates that this process can produce a significant sulfamyl fluoride yield at FSA:urea ratios below 2.0:1.

[0069] manner Embodiment 1 is a process for producing a sulfamyl fluoride composition, the process comprising: providing a solution containing fluorosulfonic acid, urea, and a solvent, wherein the molar ratio of fluorosulfonic acid to urea is about 1.80:1 to about 2.00:1; reacting the solution at a reaction temperature of 80°C to about 170°C to produce a mixture containing sulfamyl fluoride, bis(fluorosulfonyl)imide, ammonium fluorosulfate, and a solvent; separating ammonium fluorosulfate from the mixture; and separating the mixture into a sulfamyl fluoride composition and a recycled composition, wherein the sulfamyl fluoride composition contains higher concentrations of sulfamyl fluoride and bis(fluorosulfonyl)imide than the recycled composition.

[0070] Embodiment 2 is the process according to Embodiment 1, further comprising recycling the recycled composition back into the step of reacting it.

[0071] Embodiment 3 is the process described in Embodiment 1 or Embodiment 2, wherein the process is a continuous process.

[0072] Embodiment 4 is the process described in Embodiment 1 or Embodiment 2, wherein the process is a semi-batch process.

[0073] Embodiment 5 is the process according to any one of Embodiments 1 to 4, wherein the solvent comprises at least one selected from bis(fluorosulfonyl)imide, sulfolane, and dimethylformamide.

[0074] Embodiment 6 is a process and the processes of Embodiments 1 to 5, wherein the concentration of sulfamyl fluoride in the sulfamyl fluoride composition is about 1 mole percent to about 10 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide.

[0075] Embodiment 7 is the process according to any one of Embodiments 1 to 6, wherein in the step of providing, the molar ratio of fluorosulfonic acid to urea is about 1.80:1 to about 1.90:1, and in the step of separating the mixture into a sulfamyl fluoride composition and a recycled composition, the concentration of sulfamyl fluoride in the sulfamyl fluoride composition is about 4 mole percent to about 8 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide.

[0076] Embodiment 8 is a process according to any one of Embodiments 1 to 7, wherein the separation of ammonium fluorosulfate from the mixture comprises evaporating the mixture to form a sulfamyl fluoride composition.

[0077] Embodiment 9 is a process according to any one of Embodiments 1 to 10, wherein separating the mixture into a sulfamyl fluoride composition and a recycled composition includes distilling the mixture.

[0078] Embodiment 10 is the process according to any one of Embodiments 1 to 9, further comprising separating sulfamyl fluoride from a sulfamyl fluoride composition to form a concentrated sulfamyl fluoride composition, wherein the concentration of sulfamyl fluoride in the concentrated sulfamyl fluoride composition is about 50% by weight to about 99.9% by weight of the concentrated sulfamyl fluoride composition.

[0079] Embodiment 11 involves mixing a sulfamyl fluoride composition with additional fluorosulfonic acid and reacting the mixture of the sulfamyl fluoride composition and the additional fluorosulfonic acid in a reactor at a reaction temperature of 80°C to about 170°C to produce a crude HFSI product composition and a volatile composition, wherein the volatile composition comprises fluorosulfonic acid and water, and the crude HFSI product composition comprises bis(fluorosulfonyl)imide, ammonium fluorosulfate, unreacted fluorosulfonic acid, and unreacted sulfamyl fluoride, and the unreacted sulfamyl in the crude HFSI product composition The process according to any one of embodiments 1 to 11, further comprising: generating a crude HFSI product composition in which the concentration of fluoride is less than 0.5 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide; separating ammonium fluorosulfate from the crude HFSI product composition to produce an HFSI product composition; and separating the HFSI product composition into a concentrated HFSI product composition and a top stream composition, wherein the concentrated HFSI product composition contains a higher concentration of bis(fluorosulfonyl)imide than the top stream composition.

[0080] Embodiment 12 is the process according to Embodiment 11, further comprising separating the top stream composition into an aqueous composition and an FSA-rich composition, wherein the FSA-rich composition contains a higher concentration of fluorosulfonic acid than the aqueous composition.

[0081] Embodiment 13 is the process according to Embodiment 12, further comprising the step of mixing the FSA-rich composition with an additional fluorosulfonic acid and a sulfamyl fluoride composition, or the step of providing a solution containing fluorosulfonic acid, urea, and a solvent.

[0082] Embodiment 14 is the process described in any of Embodiments 11 to 13, wherein the process is a continuous process.

[0083] Embodiment 15 is the process described in any of Embodiments 11 to 13, wherein the process is a semi-batch process.

[0084] Embodiment 16 is the process according to any one of Embodiments 11 to 15, further comprising separating the volatile composition into an aqueous composition and an FSA-rich composition, wherein the FSA-rich composition contains a higher concentration of fluorosulfonic acid than the aqueous composition.

[0085] Embodiment 17 is the process according to Embodiment 16, further comprising the step of mixing the FSA-rich composition with an additional fluorosulfonic acid and a sulfamyl fluoride composition, or the step of providing a solution containing fluorosulfonic acid, urea, and a solvent.

[0086] Embodiment 18 is the process described in Embodiment 17, wherein the process is a continuous process.

[0087] Embodiment 19 is the process described in Embodiment 17, wherein the process is a semi-batch process.

[0088] Embodiment 20 is a composition comprising sulfamyl fluoride and bis(fluorosulfonyl)imide, wherein the concentration of sulfamyl fluoride is about 1 mole percent to about 10 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide.

[0089] Embodiment 21 is the composition according to Embodiment 20, wherein the concentration of sulfamyl fluoride is about 2 mole percent to about 9 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide.

[0090] Embodiment 22 is the composition according to Embodiment 20, wherein the concentration of sulfamyl fluoride is about 3 mole percent to about 8 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide.

[0091] Embodiment 23 is the composition according to Embodiment 20, wherein the concentration of sulfamyl fluoride is about 4 mole percent to about 8 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide.

[0092] Embodiment 24 is a composition comprising sulfamyl fluoride and bis(fluorosulfonyl)imide, wherein the concentration of sulfamyl fluoride is about 50% to about 99.9% by weight of the composition.

[0093] Embodiment 25 is the composition according to Embodiment 24, wherein the concentration of sulfamyl fluoride is about 90% to about 99.9% by weight of the composition.

[0094] Embodiment 26 is the composition according to Embodiment 24, wherein the concentration of sulfamyl fluoride is about 95% to about 99.9% by weight of the composition.

[0095] Embodiment 27 is the composition according to Embodiment 25, wherein the concentration of sulfamyl fluoride is about 99.5% to about 99.9% by weight of the composition. The present invention includes the following embodiments. [1] A process for producing a sulfamyl fluoride composition, To provide a solution comprising fluorosulfonic acid, urea, and a solvent, wherein the molar ratio of fluorosulfonic acid to urea is approximately 1.80:1 to approximately 2.00:1. The aforementioned solution is reacted at a reaction temperature of 80°C to approximately 170°C to produce a mixture containing sulfamyl fluoride, bis(fluorosulfonyl)imide, ammonium fluorosulfate, and the aforementioned solvent. Separating the ammonium fluorosulfate from the mixture, A process comprising separating the mixture into the sulfamyl fluoride composition and the recycled composition, wherein the sulfamyl fluoride composition contains higher concentrations of sulfamyl fluoride and bis(fluorosulfonyl)imide than the recycled composition. [2] The process according to claim 1, further comprising recycling the recycled composition back into the reacting step. [3] The process described in item 2, wherein the process is a continuous process. [4] The process described in item 1, wherein the process is a semi-batch process. [5] The process according to claim 1, wherein the solvent comprises at least one selected from bis(fluorosulfonyl)imide, sulfolane, and dimethylformamide. [6] The process according to item 1, wherein the concentration of the sulfamyl fluoride in the sulfamyl fluoride composition is about 1 mole percent to about 10 mole percent of the combination of the sulfamyl fluoride and bis(fluorosulfonyl)imide. [7] The process according to item 1, wherein in the step of providing, the molar ratio of the fluorosulfonic acid to the urea is about 1.80:1 to about 1.90:1, and in the step of separating the mixture into the sulfamyl fluoride composition and the recycled composition, the concentration of the sulfamyl fluoride in the sulfamyl fluoride composition is about 4 mole percent to about 8 mole percent of the combination of the sulfamyl fluoride and bis(fluorosulfonyl)imide. [8] The process according to claim 1, wherein separating the ammonium fluorosulfate from the mixture comprises evaporating the mixture to form the sulfamyl fluoride composition. [9] The process according to claim 1, wherein separating the mixture into a sulfamyl fluoride composition and a recycled composition includes distilling the mixture.

[10] The process according to claim 1, further comprising separating the sulfamyl fluoride from the sulfamyl fluoride composition to form a concentrated sulfamyl fluoride composition, wherein the concentration of sulfamyl fluoride in the concentrated sulfamyl fluoride composition is about 50% by weight to about 99.9% by weight of the concentrated sulfamyl fluoride composition.

[11] The sulfamyl fluoride composition is mixed with an additional fluorosulfonic acid, The process involves reacting the mixture of the sulfamyl fluoride composition and the additional fluorosulfonic acid in a reactor at a reaction temperature of 80°C to approximately 170°C to produce a crude HFSI product composition and a volatile composition, wherein the volatile composition contains fluorosulfonic acid and water, and the crude HFSI product composition contains bis(fluorosulfonyl)imide, ammonium fluorosulfate, unreacted fluorosulfonic acid, and unreacted sulfamyl fluoride, and the concentration of unreacted sulfamyl fluoride in the crude HFSI product composition is less than 0.5 mole percent of the combined amount of sulfamyl fluoride and bis(fluorosulfonyl)imide. The ammonium fluorosulfate is separated from the crude HFSI product composition to produce the HFSI product composition, The process according to claim 1, further comprising separating the HFSI product composition into a concentrated HFSI product composition and a top stream composition, wherein the concentrated HFSI product composition contains a higher concentration of bis(fluorosulfonyl)imide than the top stream composition.

[12] A composition, Sulfamyl fluoride and A composition comprising a bis(fluorosulfonyl)imide, wherein the concentration of the sulfamyl fluoride is about 1 mole percent to about 10 mole percent of the combination of the sulfamyl fluoride and the bis(fluorosulfonyl)imide.

[13] 12 The composition according to item 12, wherein the concentration of the sulfamyl fluoride is about 2 mole percent to about 9 mole percent of the combination of the sulfamyl fluoride and the bis(fluorosulfonyl)imide.

[14] The composition according to item 12, wherein the concentration of the sulfamyl fluoride is about 3 mole percent to about 8 mole percent of the combination of the sulfamyl fluoride and the bis(fluorosulfonyl)imide.

[15] The composition according to claim 12, wherein the concentration of the sulfamyl fluoride is about 4 mole percent to about 8 mole percent of the combination of the sulfamyl fluoride and the bis(fluorosulfonyl)imide.

Claims

1. A process for producing a sulfamyl fluoride composition, To provide a solution comprising fluorosulfonic acid, urea, and a solvent, wherein the molar ratio of fluorosulfonic acid to urea is 1.80:1 to 2.00:

1. The above solution is reacted at a reaction temperature of 80°C to 170°C to produce a mixture containing sulfamyl fluoride, bis(fluorosulfonyl)imide, ammonium fluorosulfate, and the solvent. Separating the ammonium fluorosulfate from the mixture, A process comprising separating the mixture into the sulfamyl fluoride composition and the recycled composition, wherein the sulfamyl fluoride composition contains higher concentrations of sulfamyl fluoride and bis(fluorosulfonyl)imide than the recycled composition.

2. The process according to claim 1, further comprising recycling the recycled composition back into the reaction step.

3. The process according to claim 2, wherein the process is a continuous process.

4. The process according to claim 1, wherein the process is a semi-batch process.

5. The process according to claim 1, wherein the solvent comprises at least one selected from bis(fluorosulfonyl)imide, sulfolane, and dimethylformamide.

6. The process according to claim 1, wherein the concentration of the sulfamyl fluoride in the sulfamyl fluoride composition is 1 mole percent to 10 mole percent of the combination of the sulfamyl fluoride and bis(fluorosulfonyl)imide.

7. The process according to claim 1, wherein in the step of providing, the molar ratio of the fluorosulfonic acid to the urea is 1.80:1 to 1.90:1, and in the step of separating the mixture into the sulfamyl fluoride composition and the recycled composition, the concentration of the sulfamyl fluoride in the sulfamyl fluoride composition is 4 mole percent to 8 mole percent of the combination of the sulfamyl fluoride and bis(fluorosulfonyl)imide.

8. The process according to claim 1, wherein separating the ammonium fluorosulfate from the mixture comprises evaporating the mixture to form the sulfamyl fluoride composition.

9. The process according to claim 1, wherein separating the mixture into a sulfamyl fluoride composition and a recycled composition includes distilling the mixture.

10. The process according to claim 1, further comprising separating the sulfamyl fluoride from the sulfamyl fluoride composition to form a concentrated sulfamyl fluoride composition, wherein the concentration of sulfamyl fluoride in the concentrated sulfamyl fluoride composition is 50% by weight to 99.9% by weight of the concentrated sulfamyl fluoride composition.

11. The sulfamyl fluoride composition is mixed with an additional fluorosulfonic acid, The method involves reacting the mixture of the sulfamyl fluoride composition and the additional fluorosulfonic acid in a reactor at a reaction temperature of 80°C to 170°C to produce a crude HFSI product composition and a volatile composition, wherein the volatile composition comprises fluorosulfonic acid and water, and the crude HFSI product composition comprises bis(fluorosulfonyl)imide, ammonium fluorosulfate, unreacted fluorosulfonic acid, and unreacted sulfamyl fluoride, and the concentration of unreacted sulfamyl fluoride in the crude HFSI product composition is less than 0.5 mole percent of the combination of sulfamyl fluoride and bis(fluorosulfonyl)imide. The ammonium fluorosulfate is separated from the crude HFSI product composition to produce an HFSI product composition, The process according to claim 1, further comprising separating the HFSI product composition into a concentrated HFSI product composition and a top stream composition, wherein the concentrated HFSI product composition contains a higher concentration of bis(fluorosulfonyl)imide than the top stream composition.

12. A composition, Sulfamyl fluoride and A composition comprising a bis(fluorosulfonyl)imide, wherein the concentration of the sulfamyl fluoride is 2 mole percent to 10 mole percent of the combination of the sulfamyl fluoride and the bis(fluorosulfonyl)imide.

13. The composition according to claim 12, wherein the concentration of the sulfamyl fluoride is 2 mole percent to 9 mole percent of the combination of the sulfamyl fluoride and the bis(fluorosulfonyl)imide.

14. The composition according to claim 12, wherein the concentration of the sulfamyl fluoride is 3 mole percent to 8 mole percent of the combination of the sulfamyl fluoride and the bis(fluorosulfonyl)imide.

15. The composition according to claim 12, wherein the concentration of the sulfamyl fluoride is 4 mole percent to 8 mole percent of the combination of the sulfamyl fluoride and the bis(fluorosulfonyl)imide.

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