Integrated process and catalyst for producing hydrogen iodide from hydrogen and iodine

Abstract

The present invention provides a process for producing hydrogen iodide. The process includes providing a gas-phase reactant stream comprising hydrogen and iodine, and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst includes at least one selected from the group consisting of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide. The catalyst is supported on a support.

Description

[Technical field]

[0001] The present disclosure relates to a process for producing hydrogen iodide. In particular, the present disclosure relates to a process for producing anhydrous hydrogen iodide from hydrogen and iodine in the presence of a catalyst. [Background technology]

[0002] Hydrogen iodide is an important industrial chemical used as a reducing agent and in the preparation of hydroiodic acid, organic and inorganic iodides, and iodoalkanes. However, hydrogen iodide is very difficult to handle due to its instability and reactivity. For example, hydrogen iodide decomposes in the presence of heat or light to form hydrogen and iodine. Furthermore, in the presence of moisture, hydrogen iodide forms hydroiodic acid, which can corrode most metals. The instability and reactivity of hydrogen iodide makes it difficult to store and transport. Therefore, anhydrous hydrogen iodide is often prepared locally for immediate use.

[0003] Various methods for producing hydrogen iodide have been reported, see, for example, NN Greenwood et al., The Chemistry of the Elements, 2nd edition, Oxford: Butterworth-Heineman, p809-815, 1997, where hydrogen iodide is prepared from the reaction of elemental iodine with hydrazine according to the following equation 1: Equation 1: 2I2+N2H4→4HI+N2

[0004] In another embodiment, the method includes the steps of: rd In this edition, AI Vogel teaches that hydrogen iodide can be prepared by reacting a stream of hydrogen sulfide with iodine according to the following equation 2: Equation 2: H2S+I2→2HI+S Summary of the Invention [Problem to be solved by the invention]

[0005] Each of the above examples uses expensive starting materials such as hydrogen sulfide or hydrazine, which limits their use for the economical preparation of large quantities of hydrogen iodide. Furthermore, the use of hydrazine for the preparation of hydrogen iodide results in the formation of nitrogen gas as a by-product. It is difficult and expensive to separate the nitrogen gas from hydrogen iodide to purify hydrogen iodide, thus increasing production costs. Similarly, the use of hydrogen sulfide results in the formation of sulfur, which is difficult to separate from unreacted iodine, increasing production costs. Sulfur may weaken any catalyst used, further increasing production costs.

[0006] In some other embodiments, hydrogen iodide is prepared from elemental iodine and hydrogen gas according to Equation 3 below. Equation 3: H2+I2→2HI Such an embodiment may more easily produce high purity hydrogen iodide since no nitrogen or sulfur is produced. For example, JP 4713895B2 shows the preparation of hydrogen iodide in gas phase using hydrogen gas and iodine vapor catalyzed by a precious metal-based catalyst. Specifically, the disclosed reaction may be catalyzed by platinum, rhodium, palladium, and ruthenium supported on a metal oxide selected from magnesium oxide, titanium oxide, silica oxide, alumina, and zirconia. However, the use of a precious metal-based catalyst for the preparation of hydrogen iodide would generally further increase the production cost due to the high cost of precious metals. Therefore, there is a need for an alternative metal catalyst that does not contain precious metals to catalyze the reaction of hydrogen with iodine to produce hydrogen iodide.

[0007] The present disclosure provides an integrated process for the production of hydrogen iodide (HI) from hydrogen (H2) and elemental iodine (I2), comprising the use of a catalyst comprising at least one selected from the group of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide supported on a support.

[0008] In one embodiment, the present invention provides a process for producing hydrogen iodide. The process includes providing a gas-phase reactant stream comprising hydrogen and iodine, and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst includes at least one selected from the group of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide. The catalyst is supported on a support.

[0009] In another embodiment, the present invention provides a process for producing hydrogen iodide. The process includes reacting hydrogen and iodine in the gas phase in the presence of a catalyst to produce a product stream containing hydrogen iodide and unreacted iodine, removing at least a portion of the unreacted iodine from the product stream by cooling the product stream to form solid iodine, producing liquid iodine from the solid iodine, and recycling the liquefied iodine to the reaction step. The solid iodine is formed in a first iodine removal tank or a second iodine removal tank. The liquid iodine is produced from the solid iodine by heating the first iodine removal tank to liquefy the solid iodine when the product stream is passed through the second iodine removal tank to cool, or by heating the second iodine removal tank to liquefy the solid iodine when the product stream is passed through the first iodine removal tank to cool. The catalyst includes at least one selected from the group consisting of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide. The catalyst is supported on a carrier. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a process flow diagram illustrating an integrated process for producing anhydrous hydrogen iodide.

[0011] [Diagram 2] FIG. 2 is a process flow diagram illustrating another integrated process for producing anhydrous hydrogen iodide. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present disclosure provides an integrated process for the production of anhydrous hydrogen iodide (HI) from hydrogen (H2) and elemental iodine (I2), including the use of nickel, cobalt, iron, nickel oxide, cobalt oxide, and / or iron oxide catalysts supported on a carrier. The use of such catalysts has been found to provide efficient production of hydrogen iodide on a commercial scale. The efficiency of hydrogen iodide production is further improved by regenerating the reactants. Regeneration of elemental iodine is particularly important because it is an expensive raw material with a bulk price of approximately $20-$100 per kilogram. However, regeneration of iodine presents a challenge because iodine is a solid below 113.7°C. The present disclosure also provides an integrated process for producing hydrogen iodide, including efficient and continuous regeneration of iodine.

[0013] As disclosed herein, anhydrous hydrogen iodide is produced from a reactant stream including hydrogen (H2) and iodine (I2). The reactant stream may consist essentially of hydrogen, iodine, and recycled hydrogen iodide. The reactant stream may consist of hydrogen, iodine, and hydrogen iodide.

[0014] The term "anhydrous hydrogen iodide" refers to hydrogen iodide that is substantially free of water. That is, any water in anhydrous hydrogen iodide is less than about 500 ppm by weight, about 300 ppm by weight, about 200 ppm by weight, about 100 ppm by weight, about 50 ppm by weight, about 30 ppm by weight, about 20 ppm by weight, about 10 ppm by weight, about 5 ppm by weight, about 3 ppm by weight, about 2 ppm by weight, or about 1 ppm by weight, or any value defined between any two of the aforementioned values. Preferably, anhydrous hydrogen iodide contains water in an amount of less than about 100 ppm by weight. More preferably, anhydrous hydrogen iodide contains water in an amount of less than about 10 ppm by weight. Most preferably, anhydrous hydrogen iodide contains water in an amount of less than about 1 ppm by weight.

[0015] It is preferred to have as little water as possible in the reactant streams, since the presence of moisture results in the formation of hydroiodic acid, which is corrosive and can be harmful to downstream equipment and process lines. Additionally, recovering hydrogen iodide from hydroiodic acid increases production costs.

[0016] The hydrogen is substantially free of water, and contains water in an amount of less than about 500 ppm by weight, less than about 300 ppm by weight, less than about 200 ppm by weight, less than about 100 ppm by weight, less than about 50 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than 10 ppm by weight, or less than about 5 ppm by weight, or any value defined between any two of the aforementioned values. Preferably, the hydrogen contains any water in an amount of less than about 50 ppm by weight. More preferably, the hydrogen contains any water in an amount of less than about 10 ppm by weight. Most preferably, the hydrogen contains any water in an amount of less than about 5 ppm by weight.

[0017] The hydrogen is substantially free of oxygen. That is, any oxygen in the hydrogen is less than about 500 ppm by weight, less than about 300 ppm by weight, less than about 200 ppm by weight, less than about 100 ppm by weight, less than about 50 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, less than about 10 ppm by weight, less than about 5 ppm by weight, less than about 3 ppm by weight, less than about 2 ppm by weight, or less than about 1 ppm by weight, or any value defined between any two of the aforementioned values. Preferably, the amount of oxygen in the hydrogen is less than about 100 ppm by weight. More preferably, the amount of oxygen in the hydrogen is less than about 10 ppm by weight. Most preferably, the amount of oxygen in the hydrogen is less than about 1 ppm by weight. It is preferred that there is as little oxygen as possible in the hydrogen, since oxygen can react with hydrogen to form water.

[0018] The iodine is substantially free of water, and contains water in an amount of less than about 500 ppm by weight, less than about 300 ppm by weight, less than about 200 ppm by weight, less than about 100 ppm by weight, less than about 50 ppm by weight, less than about 30 ppm by weight, less than about 20 ppm by weight, or less than about 10 ppm by weight, or any value defined between any two of the aforementioned values. Preferably, the iodine contains any water in an amount of less than about 100 ppm by weight. More preferably, the iodine contains any water in an amount of less than about 30 ppm by weight. Most preferably, the iodine contains any water in an amount of less than about 10 ppm by weight.

[0019] Elemental iodine in solid form is commercially available, for example, from SQM, Santiago, Chile, or Kanto Natural Gas Development Co., Ltd, Chiba, Japan. Hydrogen in compressed gas form is commercially available, for example, from Airgas, Radnor, PA, or from Air Products and Chemicals, Inc. (Allentown, PA).

[0020] In the reactant stream, the molar ratio of hydrogen to iodine may be as low as, for example, about 1:1, about 1.5:1, about 2:1, about 2.5:1, about 2.7:1, or about 3:1, or as high as about 4:1, about 5:1, about 6:1, about 7:1, about 8:1, about 9:1, or about 10:1, or within any range defined between any two of the foregoing values, such as about 1:1 to about 10:1, about 2:1 to about 8:1, about 3:1 to about 6:1, about 2:1 to about 5:1, about 2:1 to about 3:1, about 2.5:1 to about 3:1, or about 2.7:1 to about 3.0:1. Preferably, the molar ratio of hydrogen to iodine is about 2:1 to about 5:1. More preferably, the molar ratio of hydrogen to iodine is about 2:1 to about 3:1. Most preferably, the molar ratio of hydrogen to iodine is from about 2.5:1 to about 3:1.

[0021] The reactant stream reacts in the presence of a catalyst contained within the reactor to produce a product stream comprising anhydrous hydrogen iodide according to Equation 3 above. The reactor may be a heated tube reactor, such as a fixed-bed tubular reactor, including a tube containing the catalyst. The tube may be made of metal, such as stainless steel, nickel, and / or nickel alloys, e.g., nickel-chromium alloys, nickel-molybdenum alloys, nickel-chromium-molybdenum alloys, nickel-iron-chromium alloys, or nickel-copper alloys. By heating the tube reactor, the catalyst is also heated. Alternatively, the reactor may be any type of packed reactor, such as a multi-tube reactor (e.g., a shell-and-tube reactor), in which the catalyst is packed into the tube and a heat transfer medium is in contact with the outside of the tube. The reactor may be operated isothermally or adiabatically.

[0022] As mentioned above, the catalyst is a nickel, cobalt, iron, nickel oxide, cobalt oxide, and / or iron oxide catalyst on a support. Thus, the catalyst comprises at least one selected from the group of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide, and the catalyst is supported on a support. The support may be selected from the group of activated carbon, silica gel, zeolite, silicon carbide, metal oxides, and combinations thereof. Non-exclusive examples of metal oxides include alumina, magnesium oxide, titanium oxide, zinc oxide, zirconia, chromia, and combinations thereof.

[0023] The catalyst may comprise nickel on a silica gel support. The catalyst may comprise nickel on a zeolite support. The catalyst may comprise nickel on an activated carbon support. The catalyst may comprise nickel on a silicon carbide support. The catalyst may consist essentially of nickel on a silica gel support. The catalyst may consist essentially of nickel on a zeolite support. The catalyst may consist essentially of nickel on an activated carbon support. The catalyst may consist essentially of nickel on a silicon carbide support. The catalyst may consist of nickel on a silica gel support. The catalyst may consist of nickel on a zeolite support. The catalyst may consist of nickel on an activated carbon support. The catalyst may consist of nickel on a silicon carbide support.

[0024] The catalyst may comprise nickel on a metal oxide support. The catalyst may consist essentially of nickel on a metal oxide support. The catalyst may consist of nickel on a metal oxide support. The catalyst may comprise nickel on an alumina support. The catalyst may comprise nickel on a magnesium oxide support. The catalyst may comprise nickel on a titanium oxide support. The catalyst may comprise nickel on a zinc oxide support. The catalyst may comprise nickel on a zirconia support. The catalyst may comprise nickel on a chromia support. The catalyst may consist essentially of nickel on an alumina support. The catalyst may consist essentially of nickel on a magnesium oxide support. The catalyst may consist essentially of nickel on a titanium oxide support. The catalyst may consist essentially of nickel on a zinc oxide support. The catalyst may consist essentially of nickel on a zirconia support. The catalyst may consist essentially of nickel on a chromia support. The catalyst may consist of nickel on an alumina support. The catalyst may consist of nickel on a magnesium oxide support. The catalyst may consist of nickel on a titanium oxide support. The catalyst may be comprised of nickel on a zinc oxide support.The catalyst may be comprised of nickel on a zirconia support.The catalyst may be comprised of nickel on a chromia support.

[0025] The catalyst may comprise nickel oxide on a silica gel support. The catalyst may comprise nickel oxide on a zeolite support. The catalyst may comprise nickel oxide on an activated carbon support. The catalyst may comprise nickel oxide on a silicon carbide support. The catalyst may consist essentially of nickel oxide on a silica gel support. The catalyst may consist essentially of nickel oxide on a zeolite support. The catalyst may consist essentially of nickel oxide on an activated carbon support. The catalyst may consist essentially of nickel oxide on a silicon carbide support. The catalyst may consist of nickel oxide on a silica gel support. The catalyst may consist of nickel oxide on a zeolite support. The catalyst may consist of nickel oxide on an activated carbon support. The catalyst may consist of nickel oxide on a silicon carbide support.

[0026] The catalyst may comprise nickel oxide on a metal oxide support. The catalyst may consist essentially of nickel oxide on a metal oxide support. The catalyst may consist of nickel oxide on a metal oxide support. The catalyst may comprise nickel oxide on an alumina support. The catalyst may comprise nickel oxide on a magnesium oxide support. The catalyst may comprise nickel oxide on a titanium oxide support. The catalyst may comprise nickel oxide on a zinc oxide support. The catalyst may comprise nickel oxide on a zirconia support. The catalyst may comprise nickel oxide on a chromia support. The catalyst may consist essentially of nickel oxide on an alumina support. The catalyst may consist essentially of nickel oxide on a magnesium oxide support. The catalyst may consist essentially of nickel oxide on a titanium oxide support. The catalyst may consist essentially of nickel oxide on a zinc oxide support. The catalyst may consist essentially of nickel oxide on a zirconia support. The catalyst may consist essentially of nickel oxide on a chromia support. The catalyst may consist essentially of nickel oxide on an alumina support. The catalyst may consist of nickel oxide on a magnesium oxide support. The catalyst may be comprised of nickel oxide on a titanium oxide support. The catalyst may be comprised of nickel oxide on a zinc oxide support. The catalyst may be comprised of nickel oxide on a zirconia support. The catalyst may be comprised of nickel oxide on a chromia support.

[0027] The catalyst may comprise nickel and nickel oxide on a silica gel support. The catalyst may comprise nickel and nickel oxide on a zeolite support. The catalyst may comprise nickel and nickel oxide on an activated carbon support. The catalyst may comprise nickel and nickel oxide on a silicon carbide support. The catalyst may consist essentially of nickel and nickel oxide on a silica gel support. The catalyst may consist essentially of nickel and nickel oxide on a zeolite support. The catalyst may consist essentially of nickel and nickel oxide on an activated carbon support. The catalyst may consist essentially of nickel and nickel oxide on a silicon carbide support. The catalyst may consist of nickel and nickel oxide on a silica gel support. The catalyst may consist of nickel and nickel oxide on a zeolite support. The catalyst may consist of nickel and nickel oxide on an activated carbon support. The catalyst may consist of nickel and nickel oxide on a silicon carbide support.

[0028] The catalyst may comprise nickel and nickel oxide on a metal oxide support. The catalyst may consist essentially of nickel and nickel oxide on a metal oxide support. The catalyst may consist of nickel and nickel oxide on a metal oxide support. The catalyst may comprise nickel and nickel oxide on an alumina support. The catalyst may comprise nickel and nickel oxide on a magnesium oxide support. The catalyst may comprise nickel and nickel oxide on a titanium oxide support. The catalyst may comprise nickel and nickel oxide on a zinc oxide support. The catalyst may comprise nickel and nickel oxide on a zirconia support. The catalyst may comprise nickel and nickel oxide on a chromia support. The catalyst may consist essentially of nickel and nickel oxide on an alumina support. The catalyst may consist essentially of nickel and nickel oxide on a magnesium oxide support. The catalyst may consist essentially of nickel and nickel oxide on a titanium oxide support. The catalyst may consist essentially of nickel and nickel oxide on a zinc oxide support. The catalyst may consist essentially of nickel and nickel oxide on a zirconia support. The catalyst may consist essentially of nickel and nickel oxide on a chromia support. The catalyst may be comprised of nickel and nickel oxide on an alumina support. The catalyst may be comprised of nickel and nickel oxide on a magnesium oxide support. The catalyst may be comprised of nickel and nickel oxide on a titanium oxide support. The catalyst may be comprised of nickel and nickel oxide on a zinc oxide support. The catalyst may be comprised of nickel and nickel oxide on a zirconia support. The catalyst may be comprised of nickel and nickel oxide on a chromia support.

[0029] The catalyst may comprise cobalt on a silica gel support. The catalyst may comprise cobalt on a zeolite support. The catalyst may comprise cobalt on an activated carbon support. The catalyst may comprise cobalt on a silicon carbide support. The catalyst may consist essentially of cobalt on a silica gel support. The catalyst may consist essentially of cobalt on a zeolite support. The catalyst may consist essentially of cobalt on an activated carbon support. The catalyst may consist essentially of cobalt on a silicon carbide support. The catalyst may consist of cobalt on a silica gel support. The catalyst may consist of cobalt on a zeolite support. The catalyst may consist of cobalt on an activated carbon support. The catalyst may consist of cobalt on a silicon carbide support.

[0030] The catalyst may comprise cobalt on a metal oxide support. The catalyst may consist essentially of cobalt on a metal oxide support. The catalyst may consist of cobalt on a metal oxide support. The catalyst may comprise cobalt on an alumina support. The catalyst may comprise cobalt on a magnesium oxide support. The catalyst may comprise cobalt on a titanium oxide support. The catalyst may comprise cobalt on a zinc oxide support. The catalyst may comprise cobalt on a zirconia support. The catalyst may comprise cobalt on a chromia support. The catalyst may consist essentially of cobalt on an alumina support. The catalyst may consist essentially of cobalt on a magnesium oxide support. The catalyst may consist essentially of cobalt on a titanium oxide support. The catalyst may consist essentially of cobalt on a zinc oxide support. The catalyst may consist essentially of cobalt on a zirconia support. The catalyst may consist essentially of cobalt on a chromia support. The catalyst may consist essentially of cobalt on an alumina support. The catalyst may comprise cobalt on a magnesium oxide support. The catalyst may comprise cobalt on a titanium oxide support. The catalyst may comprise cobalt on a zinc oxide support. The catalyst may comprise cobalt on a zirconia support. The catalyst may comprise cobalt on a chromia support.

[0031] The catalyst may comprise cobalt oxide on a silica gel support. The catalyst may comprise cobalt oxide on a zeolite support. The catalyst may comprise cobalt oxide on an activated carbon support. The catalyst may comprise cobalt oxide on a silicon carbide support. The catalyst may consist essentially of cobalt oxide on a silica gel support. The catalyst may consist essentially of cobalt oxide on a zeolite support. The catalyst may consist essentially of cobalt oxide on an activated carbon support. The catalyst may consist essentially of cobalt oxide on a silicon carbide support. The catalyst may consist of cobalt oxide on a silica gel support. The catalyst may consist of cobalt oxide on a zeolite support. The catalyst may consist of cobalt oxide on an activated carbon support. The catalyst may consist of cobalt oxide on a silicon carbide support.

[0032] The catalyst may comprise cobalt oxide on a metal oxide support. The catalyst may consist essentially of cobalt oxide on a metal oxide support. The catalyst may consist of cobalt oxide on a metal oxide support. The catalyst may comprise cobalt oxide on an alumina support. The catalyst may comprise cobalt oxide on a magnesium oxide support. The catalyst may comprise cobalt oxide on a titanium oxide support. The catalyst may comprise cobalt oxide on a zinc oxide support. The catalyst may comprise cobalt oxide on a zirconia support. The catalyst may comprise cobalt oxide on a chromia support. The catalyst may consist essentially of cobalt oxide on an alumina support. The catalyst may consist essentially of cobalt oxide on a magnesium oxide support. The catalyst may consist essentially of cobalt oxide on a titanium oxide support. The catalyst may consist essentially of cobalt oxide on a zinc oxide support. The catalyst may consist essentially of cobalt oxide on a zirconia support. The catalyst may consist essentially of cobalt oxide on a chromia support. The catalyst may be comprised of cobalt oxide on an alumina support. The catalyst may be comprised of cobalt oxide on a magnesium oxide support. The catalyst may be comprised of cobalt oxide on a titanium oxide support. The catalyst may be comprised of cobalt oxide on a zinc oxide support. The catalyst may be comprised of cobalt oxide on a zirconia support. The catalyst may be comprised of cobalt oxide on a chromia support.

[0033] The catalyst may comprise cobalt and cobalt oxide on a silica gel support. The catalyst may comprise cobalt and cobalt oxide on a zeolite support. The catalyst may comprise cobalt and cobalt oxide on an activated carbon support. The catalyst may comprise cobalt and cobalt oxide on a silicon carbide support. The catalyst may consist essentially of cobalt and cobalt oxide on a silica gel support. The catalyst may consist essentially of cobalt and cobalt oxide on a zeolite support. The catalyst may consist essentially of cobalt and cobalt oxide on an activated carbon support. The catalyst may consist essentially of cobalt and cobalt oxide on a silicon carbide support. The catalyst may consist of cobalt and cobalt oxide on a silica gel support. The catalyst may consist of cobalt and cobalt oxide on a zeolite support. The catalyst may consist of cobalt and cobalt oxide on an activated carbon support. The catalyst may consist of cobalt and cobalt oxide on a silicon carbide support.

[0034] The catalyst may comprise cobalt and cobalt oxide on a metal oxide support. The catalyst may consist essentially of cobalt and cobalt oxide on a metal oxide support. The catalyst may consist of cobalt and cobalt oxide on a metal oxide support. The catalyst may comprise cobalt and cobalt oxide on an alumina support. The catalyst may comprise cobalt and cobalt oxide on a magnesium oxide support. The catalyst may comprise cobalt and cobalt oxide on a titanium oxide support. The catalyst may comprise cobalt and cobalt oxide on a zinc oxide support. The catalyst may comprise cobalt and cobalt oxide on a zirconia support. The catalyst may comprise cobalt and cobalt oxide on a chromia support. The catalyst may consist essentially of cobalt and cobalt oxide on an alumina support. The catalyst may consist essentially of cobalt and cobalt oxide on a magnesium oxide support. The catalyst may consist essentially of cobalt and cobalt oxide on a titanium oxide support. The catalyst may consist essentially of cobalt and cobalt oxide on a zinc oxide support. The catalyst may consist essentially of cobalt and cobalt oxide on a zirconia support. The catalyst may consist essentially of cobalt and cobalt oxide on a chromia support. The catalyst may consist of cobalt and cobalt oxide on an alumina support. The catalyst may consist of cobalt and cobalt oxide on a magnesium oxide support. The catalyst may consist of cobalt and cobalt oxide on a titanium oxide support. The catalyst may consist of cobalt and cobalt oxide on a zinc oxide support. The catalyst may consist of cobalt and cobalt oxide on a zirconia support. The catalyst may consist of cobalt and cobalt oxide on a chromia support.

[0035] The catalyst may comprise iron on a silica gel support. The catalyst may comprise iron on a zeolite support. The catalyst may comprise iron on an activated carbon support. The catalyst may comprise iron on a silicon carbide support. The catalyst may consist essentially of iron on a silica gel support. The catalyst may consist essentially of iron on a zeolite support. The catalyst may consist essentially of iron on an activated carbon support. The catalyst may consist essentially of iron on a silicon carbide support. The catalyst may consist of iron on a silica gel support. The catalyst may consist of iron on a zeolite support. The catalyst may consist of iron on an activated carbon support. The catalyst may consist of iron on a silicon carbide support.

[0036] The catalyst may comprise iron on a metal oxide support. The catalyst may consist essentially of iron on a metal oxide support. The catalyst may consist of iron on a metal oxide support. The catalyst may comprise iron on an alumina support. The catalyst may comprise iron on a magnesium oxide support. The catalyst may comprise iron on a titanium oxide support. The catalyst may comprise iron on a zinc oxide support. The catalyst may comprise iron on a zirconia support. The catalyst may comprise iron on a chromia support. The catalyst may consist essentially of iron on an alumina support. The catalyst may consist essentially of iron on a magnesium oxide support. The catalyst may consist essentially of iron on a titanium oxide support. The catalyst may consist essentially of iron on a zinc oxide support. The catalyst may consist essentially of iron on a zirconia support. The catalyst may consist essentially of iron on a chromia support. The catalyst may consist of iron on an alumina support. The catalyst may consist of iron on a magnesium oxide support. The catalyst may consist of iron on a titanium oxide support. The catalyst may comprise iron on a zinc oxide support. The catalyst may comprise iron on a zirconia support. The catalyst may comprise iron on a chromia support.

[0037] The catalyst may comprise iron oxide on a silica gel support. The catalyst may comprise iron oxide on a zeolite support. The catalyst may comprise iron oxide on an activated carbon support. The catalyst may comprise iron oxide on a silicon carbide support. The catalyst may consist essentially of iron oxide on a silica gel support. The catalyst may consist essentially of iron oxide on a zeolite support. The catalyst may consist essentially of iron oxide on an activated carbon support. The catalyst may consist essentially of iron oxide on a silicon carbide support. The catalyst may consist of iron oxide on a silica gel support. The catalyst may consist of iron oxide on a zeolite support. The catalyst may consist of iron oxide on an activated carbon support. The catalyst may consist of iron oxide on a silicon carbide support.

[0038] The catalyst may comprise iron oxide on a metal oxide support. The catalyst may consist essentially of iron oxide on a metal oxide support. The catalyst may consist of iron oxide on a metal oxide support. The catalyst may comprise iron oxide on an alumina support. The catalyst may comprise iron oxide on a magnesium oxide support. The catalyst may comprise iron oxide on a titanium oxide support. The catalyst may comprise iron oxide on a zinc oxide support. The catalyst may comprise iron oxide on a zirconia support. The catalyst may comprise iron oxide on a chromia support. The catalyst may consist essentially of iron oxide on an alumina support. The catalyst may consist essentially of iron oxide on a magnesium oxide support. The catalyst may consist essentially of iron oxide on a titanium oxide support. The catalyst may consist essentially of iron oxide on a zinc oxide support. The catalyst may consist essentially of iron oxide on a zirconia support. The catalyst may consist essentially of iron oxide on a chromia support. The catalyst may consist of iron oxide on an alumina support. The catalyst may consist of iron oxide on a magnesium oxide support. The catalyst may be comprised of iron oxide on a titanium oxide support. The catalyst may be comprised of iron oxide on a zinc oxide support. The catalyst may be comprised of iron oxide on a zirconia support. The catalyst may be comprised of iron oxide on a chromia support.

[0039] The catalyst may comprise iron and iron oxide on a silica gel support. The catalyst may comprise iron and iron oxide on a zeolite support. The catalyst may comprise iron and iron oxide on an activated carbon support. The catalyst may comprise iron and iron oxide on a silicon carbide support. The catalyst may consist essentially of iron and iron oxide on a silica gel support. The catalyst may consist essentially of iron and iron oxide on a zeolite support. The catalyst may consist essentially of iron and iron oxide on an activated carbon support. The catalyst may consist essentially of iron and iron oxide on a silicon carbide support. The catalyst may consist of iron and iron oxide on a silica gel support. The catalyst may consist of iron and iron oxide on a zeolite support. The catalyst may consist of iron and iron oxide on an activated carbon support. The catalyst may consist of iron and iron oxide on a silicon carbide support.

[0040] The catalyst may comprise iron and iron oxide on a metal oxide support. The catalyst may consist essentially of iron and iron oxide on a metal oxide support. The catalyst may consist of iron and iron oxide on a metal oxide support. The catalyst may comprise iron and iron oxide on an alumina support. The catalyst may comprise iron and iron oxide on a magnesium oxide support. The catalyst may comprise iron and iron oxide on a titanium oxide support. The catalyst may comprise iron and iron oxide on a zinc oxide support. The catalyst may comprise iron and iron oxide on a zirconia support. The catalyst may comprise iron and iron oxide on a chromia support. The catalyst may consist essentially of iron and iron oxide on an alumina support. The catalyst may consist essentially of iron and iron oxide on a magnesium oxide support. The catalyst may consist essentially of iron and iron oxide on a titanium oxide support. The catalyst may consist essentially of iron and iron oxide on a zinc oxide support. The catalyst may consist essentially of iron and iron oxide on a zirconia support. The catalyst may consist essentially of iron and iron oxide on a chromia support. The catalyst may be comprised of iron and iron oxide on an alumina support. The catalyst may be comprised of iron and iron oxide on a magnesium oxide support. The catalyst may be comprised of iron and iron oxide on a titanium oxide support. The catalyst may be comprised of iron and iron oxide on a zinc oxide support. The catalyst may be comprised of iron and iron oxide on a zirconia support. The catalyst may be comprised of iron and iron oxide on a chromia support.

[0041] The catalyst may comprise nickel and cobalt on a silica gel support. The catalyst may comprise nickel and cobalt on a zeolite support. The catalyst may comprise nickel and cobalt on an activated carbon support. The catalyst may comprise nickel and cobalt on a silicon carbide support. The catalyst may consist essentially of nickel and cobalt on a silica gel support. The catalyst may consist essentially of nickel and cobalt on a zeolite support. The catalyst may consist essentially of nickel and cobalt on an activated carbon support. The catalyst may consist essentially of nickel and cobalt on a silicon carbide support. The catalyst may consist of nickel and cobalt on a silica gel support. The catalyst may consist of nickel and cobalt on a zeolite support. The catalyst may consist of nickel and cobalt on an activated carbon support. The catalyst may consist of nickel and cobalt on a silicon carbide support.

[0042] The catalyst may comprise nickel and cobalt on a metal oxide support. The catalyst may consist essentially of nickel and cobalt on a metal oxide support. The catalyst may consist of nickel and cobalt on a metal oxide support. The catalyst may comprise nickel and cobalt on an alumina support. The catalyst may comprise nickel and cobalt on a magnesium oxide support. The catalyst may comprise nickel and cobalt on a titanium oxide support. The catalyst may comprise nickel and cobalt on a zinc oxide support. The catalyst may comprise nickel and cobalt on a zirconia support. The catalyst may comprise nickel and cobalt on a chromia support. The catalyst may consist essentially of nickel and cobalt on an alumina support. The catalyst may consist essentially of nickel and cobalt on a magnesium oxide support. The catalyst may consist essentially of nickel and cobalt on a titanium oxide support. The catalyst may consist essentially of nickel and cobalt on a zinc oxide support. The catalyst may consist essentially of nickel and cobalt on a zirconia support. The catalyst may consist essentially of nickel and cobalt on a chromia support. The catalyst may consist of nickel and cobalt on an alumina support. The catalyst may consist of nickel and cobalt on a magnesium oxide support. The catalyst may consist of nickel and cobalt on a titanium oxide support. The catalyst may consist of nickel and cobalt on a zinc oxide support. The catalyst may consist of nickel and cobalt on a zirconia support. The catalyst may consist of nickel and cobalt on a chromia support.

[0043] The catalyst may comprise nickel oxide and cobalt oxide on a silica gel support. The catalyst may comprise nickel oxide and cobalt oxide on a zeolite support. The catalyst may comprise nickel oxide and cobalt oxide on an activated carbon support. The catalyst may comprise nickel oxide and cobalt oxide on a silicon carbide support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a silica gel support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a zeolite support. The catalyst may consist essentially of nickel oxide and cobalt oxide on an activated carbon support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a silicon carbide support. The catalyst may consist of nickel oxide and cobalt oxide on a silica gel support. The catalyst may consist of nickel oxide and cobalt oxide on a zeolite support. The catalyst may consist of nickel oxide and cobalt oxide on an activated carbon support. The catalyst may consist of nickel oxide and cobalt oxide on a silicon carbide support.

[0044] The catalyst may comprise nickel oxide and cobalt oxide on a metal oxide support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a metal oxide support. The catalyst may consist of nickel oxide and cobalt oxide on a metal oxide support. The catalyst may comprise nickel oxide and cobalt oxide on an alumina support. The catalyst may comprise nickel oxide and cobalt oxide on a magnesium oxide support. The catalyst may comprise nickel oxide and cobalt oxide on a titanium oxide support. The catalyst may comprise nickel oxide and cobalt oxide on a zinc oxide support. The catalyst may comprise nickel oxide and cobalt oxide on a zirconia support. The catalyst may comprise nickel oxide and cobalt oxide on a chromia support. The catalyst may consist essentially of nickel oxide and cobalt oxide on an alumina support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a magnesium oxide support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a titanium oxide support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a zinc oxide support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a zirconia support. The catalyst may consist essentially of nickel oxide and cobalt oxide on a chromia support. The catalyst may consist of nickel oxide and cobalt oxide on an alumina support. The catalyst may consist of nickel oxide and cobalt oxide on a magnesium oxide support. The catalyst may consist of nickel oxide and cobalt oxide on a titanium oxide support. The catalyst may consist of nickel oxide and cobalt oxide on a zinc oxide support. The catalyst may consist of nickel oxide and cobalt oxide on a zirconia support. The catalyst may consist of nickel oxide and cobalt oxide on a chromia support.

[0045] The catalyst may comprise nickel and iron on a silica gel support. The catalyst may comprise nickel and iron on a zeolite support. The catalyst may comprise nickel and iron on an activated carbon support. The catalyst may comprise nickel and iron on a silicon carbide support. The catalyst may consist essentially of nickel and iron on a silica gel support. The catalyst may consist essentially of nickel and iron on a zeolite support. The catalyst may consist essentially of nickel and iron on an activated carbon support. The catalyst may consist essentially of nickel and iron on a silicon carbide support. The catalyst may consist of nickel and iron on a silica gel support. The catalyst may consist of nickel and iron on a zeolite support. The catalyst may consist of nickel and iron on an activated carbon support. The catalyst may consist of nickel and iron on a silicon carbide support.

[0046] The catalyst may comprise nickel and iron on a metal oxide support. The catalyst may consist essentially of nickel and iron on a metal oxide support. The catalyst may consist of nickel and iron on a metal oxide support. The catalyst may comprise nickel and iron on an alumina support. The catalyst may comprise nickel and iron on a magnesium oxide support. The catalyst may comprise nickel and iron on a titanium oxide support. The catalyst may comprise nickel and iron on a zinc oxide support. The catalyst may comprise nickel and iron on a zirconia support. The catalyst may comprise nickel and iron on a chromia support. The catalyst may consist essentially of nickel and iron on an alumina support. The catalyst may consist essentially of nickel and iron on a magnesium oxide support. The catalyst may consist essentially of nickel and iron on a titanium oxide support. The catalyst may consist essentially of nickel and iron on a zinc oxide support. The catalyst may consist essentially of nickel and iron on a zirconia support. The catalyst may consist essentially of nickel and iron on a chromia support. The catalyst may consist essentially of nickel and iron on an alumina support. The catalyst may be comprised of nickel and iron on a magnesium oxide support. The catalyst may be comprised of nickel and iron on a titanium oxide support. The catalyst may be comprised of nickel and iron on a zinc oxide support. The catalyst may be comprised of nickel and iron on a zirconia support. The catalyst may be comprised of nickel and iron on a chromia support.

[0047] The catalyst may comprise nickel oxide and iron oxide on a silica gel support. The catalyst may comprise nickel oxide and iron oxide on a zeolite support. The catalyst may comprise nickel oxide and iron oxide on an activated carbon support. The catalyst may comprise nickel oxide and iron oxide on a silicon carbide support. The catalyst may consist essentially of nickel oxide and iron oxide on a silica gel support. The catalyst may consist essentially of nickel oxide and iron oxide on a zeolite support. The catalyst may consist essentially of nickel oxide and iron oxide on an activated carbon support. The catalyst may consist essentially of nickel oxide and iron oxide on a silicon carbide support. The catalyst may consist of nickel oxide and iron oxide on a silica gel support. The catalyst may consist of nickel oxide and iron oxide on a zeolite support. The catalyst may consist of nickel oxide and iron oxide on an activated carbon support. The catalyst may consist of nickel oxide and iron oxide on a silicon carbide support.

[0048] The catalyst may comprise nickel oxide and iron oxide on a metal oxide support. The catalyst may consist essentially of nickel oxide and iron oxide on a metal oxide support. The catalyst may consist of nickel oxide and iron oxide on a metal oxide support. The catalyst may comprise nickel oxide and iron oxide on an alumina support. The catalyst may comprise nickel oxide and iron oxide on a magnesium oxide support. The catalyst may comprise nickel oxide and iron oxide on a titanium oxide support. The catalyst may comprise nickel oxide and iron oxide on a zinc oxide support. The catalyst may comprise nickel oxide and iron oxide on a zirconia support. The catalyst may comprise nickel oxide and iron oxide on a chromia support. The catalyst may consist essentially of nickel oxide and iron oxide on an alumina support. The catalyst may consist essentially of nickel oxide and iron oxide on a magnesium oxide support. The catalyst may consist essentially of nickel oxide and iron oxide on a titanium oxide support. The catalyst may consist essentially of nickel oxide and iron oxide on a zinc oxide support. The catalyst may consist essentially of nickel oxide and iron oxide on a zirconia support. The catalyst may consist essentially of nickel oxide and iron oxide on a chromia support. The catalyst may consist of nickel oxide and iron oxide on an alumina support. The catalyst may consist of nickel oxide and iron oxide on a magnesium oxide support. The catalyst may consist of nickel oxide and iron oxide on a titanium oxide support. The catalyst may consist of nickel oxide and iron oxide on a zinc oxide support. The catalyst may consist of nickel oxide and iron oxide on a zirconia support. The catalyst may consist of nickel oxide and iron oxide on a chromia support.

[0049] The catalyst may comprise cobalt and iron on a silica gel support. The catalyst may comprise cobalt and iron on a zeolite support. The catalyst may comprise cobalt and iron on an activated carbon support. The catalyst may comprise cobalt and iron on a silicon carbide support. The catalyst may consist essentially of cobalt and iron on a silica gel support. The catalyst may consist essentially of cobalt and iron on a zeolite support. The catalyst may consist essentially of cobalt and iron on an activated carbon support. The catalyst may consist essentially of cobalt and iron on a silicon carbide support. The catalyst may consist of cobalt and iron on a silica gel support. The catalyst may consist of cobalt and iron on a zeolite support. The catalyst may consist of cobalt and iron on an activated carbon support. The catalyst may consist of cobalt and iron on a silicon carbide support.

[0050] The catalyst may comprise cobalt and iron on a metal oxide support. The catalyst may consist essentially of cobalt and iron on a metal oxide support. The catalyst may consist of cobalt and iron on a metal oxide support. The catalyst may comprise cobalt and iron on an alumina support. The catalyst may comprise cobalt and iron on a magnesium oxide support. The catalyst may comprise cobalt and iron on a titanium oxide support. The catalyst may comprise cobalt and iron on a zinc oxide support. The catalyst may comprise cobalt and iron on a zirconia support. The catalyst may comprise cobalt and iron on a chromia support. The catalyst may consist essentially of cobalt and iron on an alumina support. The catalyst may consist essentially of cobalt and iron on a magnesium oxide support. The catalyst may consist essentially of cobalt and iron on a titanium oxide support. The catalyst may consist essentially of cobalt and iron on a zinc oxide support. The catalyst may consist essentially of cobalt and iron on a zirconia support. The catalyst may consist essentially of cobalt and iron on a chromia support. The catalyst may consist of cobalt and iron on an alumina support. The catalyst may consist of cobalt and iron on a magnesium oxide support. The catalyst may consist of cobalt and iron on a titanium oxide support. The catalyst may consist of cobalt and iron on a zinc oxide support. The catalyst may consist of cobalt and iron on a zirconia support. The catalyst may consist of cobalt and iron on a chromia support.

[0051] The catalyst may comprise cobalt oxide and iron oxide on a silica gel support. The catalyst may comprise cobalt oxide and iron oxide on a zeolite support. The catalyst may comprise cobalt oxide and iron oxide on an activated carbon support. The catalyst may comprise cobalt oxide and iron oxide on a silicon carbide support. The catalyst may consist essentially of cobalt oxide and iron oxide on a silica gel support. The catalyst may consist essentially of cobalt oxide and iron oxide on a zeolite support. The catalyst may consist essentially of cobalt oxide and iron oxide on an activated carbon support. The catalyst may consist essentially of cobalt oxide and iron oxide on a silicon carbide support. The catalyst may consist of cobalt oxide and iron oxide on a silica gel support. The catalyst may consist of cobalt oxide and iron oxide on a zeolite support. The catalyst may consist of cobalt oxide and iron oxide on an activated carbon support. The catalyst may consist of cobalt oxide and iron oxide on a silicon carbide support.

[0052] The catalyst may comprise cobalt oxide and iron oxide on a metal oxide support. The catalyst may consist essentially of cobalt oxide and iron oxide on a metal oxide support. The catalyst may consist of cobalt oxide and iron oxide on a metal oxide support. The catalyst may comprise cobalt oxide and iron oxide on an alumina support. The catalyst may comprise cobalt oxide and iron oxide on a magnesium oxide support. The catalyst may comprise cobalt oxide and iron oxide on a titanium oxide support. The catalyst may comprise cobalt oxide and iron oxide on a zinc oxide support. The catalyst may comprise cobalt oxide and iron oxide on a zirconia support. The catalyst may comprise cobalt oxide and iron oxide on a chromia support. The catalyst may consist essentially of cobalt oxide and iron oxide on an alumina support. The catalyst may consist essentially of cobalt oxide and iron oxide on a magnesium oxide support. The catalyst may consist essentially of cobalt oxide and iron oxide on a titanium oxide support. The catalyst may consist essentially of cobalt oxide and iron oxide on a zinc oxide support. The catalyst may consist essentially of cobalt oxide and iron oxide on a zirconia support. The catalyst may consist essentially of cobalt oxide and iron oxide on a chromia support. The catalyst may consist of cobalt oxide and iron oxide on an alumina support. The catalyst may consist of cobalt oxide and iron oxide on a magnesium oxide support. The catalyst may consist of cobalt oxide and iron oxide on a titanium oxide support. The catalyst may consist of cobalt oxide and iron oxide on a zinc oxide support. The catalyst may consist of cobalt oxide and iron oxide on a zirconia support. The catalyst may consist of cobalt oxide and iron oxide on a chromia support.

[0053] The catalyst may be in the form of beads, pellets, extrudates, powder, spheres, or mesh. Preferably, the catalyst comprises nickel on an alumina support. More preferably, the catalyst comprises nickel on an alumina support in the form of pellets. Most preferably, the catalyst comprises nickel on an alumina support in the form of pellets having a diameter in the range of about 1 mm to about 7 mm.

[0054] Catalysts are commercially available: various formulations (weight percent) of nickel metal supported on alumina are available, for example, from Honeywell UOP (Des Plaines, IL, USA) or Johnson Matthey (London, UK).

[0055] The weight percentage of the catalyst as a percentage of the total weight of the catalyst and the support may be, for example, as little as about 0.1 weight percent (wt%), about 1 wt%, about 3 wt%, about 5 wt%, about 10 wt%, about 15 wt%, or about 20 wt%, or as much as about 35 wt%, about 40 wt%, about 45 wt%, or about 50 wt%, or within any range defined between any two of the preceding values, such as about 0.1 wt% to about 50 wt%, about 3 wt% to about 45 wt%, about 10 wt% to about 40 wt%, about 15 wt% to about 35 wt%, or about 3 wt% to about 25 wt%. Preferably, the weight percentage of the catalyst is about 5 wt% to about 45 wt%. More preferably, the weight percentage of the catalyst is about 10 wt% to about 40 wt%. Most preferably, the weight percentage of the catalyst is about 15 wt% to about 35 wt%.

[0056] The catalyst may, for example, have a mass of about 1 square meter (m 2 / g), approx. 5m 2 / g, approx. 10m 2 / g, approx. 25m 2 / g, approx. 40m 2 / g, approx. 60m 2 / g, or about 80m 2 / g, or about 100 m 2 / g, approx. 120m 2 / g, approx. 150m 2 / g, approx. 200m 2 / g, approx. 250m 2 / g, approx. 300m 2 / g, or about 1,000m 2 / g or about 1 m 2 / g~about 100m 2 / g, approx. 5m 2 / g~about 300m 2 / g, approx. 10m 2 / g ~ approx. 250m 2 / g, approx. 25m 2 / g~about 200m 2 / g, approx. 40m 2 / g~about 150m 2 / g, approx. 60m 2 / g ~ approx. 120m 2 / g, or about 80m 2 / g ~ approx. 120m 2 The catalyst may have a surface area within any range defined between any two of the preceding values, such as 100 / g / g. The surface area of ​​the catalyst is determined by the BET method according to ISO 9277:2010.

[0057] The reactant streams may be contacted for contact times as short as about 0.1 seconds, about 2 seconds, about 4 seconds, about 6 seconds, about 8 seconds, about 10 seconds, about 15 seconds, about 20 seconds, about 25 seconds, or about 30 seconds, or for contact times as long as about 40 seconds, about 50 seconds, about 60 seconds, about 70 seconds, about 80 seconds, about 100 seconds, about 120 seconds, about 200 seconds, or about 1,800 seconds, or for contact times as long as about 0.1 seconds to about 1,80 seconds. The reactant stream may contact the catalyst for any contact time within any range defined between any two of the aforementioned values, such as about 0 seconds, about 2 seconds to about 120 seconds, about 4 seconds to about 100 seconds, about 6 seconds to about 80 seconds, about 8 seconds to about 70 seconds, about 10 seconds to about 60 seconds, about 15 seconds to about 50 seconds, about 20 seconds to about 40 seconds, about 20 seconds to about 30 seconds, about 10 seconds to about 20 seconds, or about 100 seconds to about 120 seconds. Preferably, the reactant stream contacts the catalyst for a contact time of about 2 seconds to about 200 seconds. More preferably, the reactant stream contacts the catalyst for a contact time of about 40 seconds to about 100 seconds. Most preferably, the reactant stream contacts the catalyst for a contact time of about 60 seconds to about 80 seconds.

[0058] The reactant streams and catalyst may be preheated to a reaction temperature, which may be as low as about 150°C, about 200°C, about 250°C, about 280°C, about 290°C, about 300°C, about 310°C, or about 320°C, or as high as about 330°C, about 340°C, about 350°C, about 360°C, about 380°C, about 400°C, about 450°C, about 500°C, about 550°C, or about 600°C. Alternatively, the reaction temperature may be within any range defined between any two of the above values, such as about 150°C to about 600°C, about 200°C to about 550°C, about 250°C to about 500°C, about 280°C to about 450°C, about 290°C to about 400°C, about 300°C to about 380°C, about 310°C to about 360°C, about 320°C to about 350°C, or about 320°C to about 340°C. Preferably, the reaction temperature is about 200°C to about 500°C. More preferably, the reaction temperature is about 300°C to about 400°C. Most preferably, the reaction temperature is about 300°C to about 350°C.

[0059] Hydrogen in the reactant stream to the reactor reduces catalysts including nickel oxide, cobalt oxide, and / or iron oxide to the corresponding metals. Preferably, such catalysts are reduced by flowing hydrogen through the reactor prior to reaction to reduce the catalyst to the corresponding metals.

[0060] The operating pressure of the reactor may be, for example, as low as about 10 kPag (kilopascals, gauge pressure), about 50 kPag, about 100 kPag, about 200 kPag, about 300 kPag, about 400 kPag, or about 600 kPag, or as high as about 800 kPag, about 1,000 kPag, about 1,500 kPag, about 2,000 kPag, about 2,500 kPag, about 3,000 kPag, or about 4,000 kPag. The operating pressure of the reactor may be within any range defined between any two of the aforementioned values, such as 10 kPag to about 4,000 kPag, about 50 kPag to about 3,000 kPag, about 100 kPag to about 2,500 kPag, about 200 kPag to about 2,000 kPag, about 300 kPag to about 1,500 kPag, about 400 kPag to about 1,000 kPag, about 600 kPag to about 800 kPag, or about 10 kPag to about 800 kPag. Preferably, the operating pressure of the reactor is about 10 kPag to about 800 kPag. More preferably, the operating pressure of the reactor is about 10 kPag to about 400 kPag. Most preferably, the operating pressure of the reactor is about 10 kPag to about 200 kPag.

[0061] Iodine is provided from solid iodine to the reactor by continuous or intermittent addition to a heated iodine liquefier to maintain a specific concentration of liquid iodine in the liquefier. A positive pressure is maintained in the liquefier to deliver the liquid iodine to the iodine evaporator. The flow rate of liquid iodine can be provided, for example, by calculating based on the pump stroke volume if a pump is used, and / or by passing the liquid iodine through a flow meter, by monitoring the weight loss of the vessel providing the iodine. The temperature of the iodine in the iodine liquefier is maintained at a temperature sufficient to dissolve the iodine, but low enough to avoid evaporation of the iodine. The liquid iodine is evaporated in the evaporator to form iodine vapor. The iodine vapor exiting the evaporator can be mixed with hydrogen gas from a hydrogen supply to form a reactant stream. Alternatively or in addition, hydrogen gas from a hydrogen supply can be fed to the iodine evaporator to aid in the evaporation of the iodine, thus reducing the evaporation temperature. In either case, the hydrogen gas may further include regenerated hydrogen gas and hydrogen iodide. The reactant streams are preheated to reaction temperature and fed to a reactor pre-charged with any of the above catalysts. The process lines between the liquefier and the vaporizer are heat traced to ensure that the iodine remains liquid in these lines. The process lines carrying the iodine vapor and the hydrogen / iodine vapor mixture are heat traced to ensure that the gas phase is maintained. Alternatively, solid iodine may be fed to a vessel where it is liquefied and vaporized to produce iodine vapor.

[0062] A product stream comprising hydrogen iodide, unreacted hydrogen, and unreacted iodine is conducted from the reactor to one or more iodine removal tanks, where the product stream is cooled to condense the unreacted iodine and remove at least a portion of the iodine from the product stream to allow it to be recycled as a reactant. Optionally, the product stream is conducted to a cooler to remove some heat from the product stream before condensing the unreacted iodine in the one or more iodine removal tanks. In the one or more iodine removal tanks, the product stream may be cooled to a temperature below the boiling point of iodine but above the melting point of iodine to recover iodine in liquid form. Alternatively, or in addition, the product stream exiting the reactor may be cooled to a temperature below the melting point of iodine to recover iodine in solid form. The product stream may proceed from the one or more iodine removal tanks to one or more additional iodine removal tanks to remove additional unreacted iodine for recycling.

[0063] A product stream substantially free of iodine may be directed from the one or more iodine removal tanks to a compressor to increase the pressure of the product stream to a separation pressure sufficient for efficient recovery of unreacted hydrogen, the separation pressure being greater than the operating pressure of the reactor. The separation pressure can be as low as about 800 kPag, about 850 kPag, about 900 kPag, about 950 kPag, or about 1,000 kPag, or as high as about 1,100 kPag, about 1,200 kPag, about 1,300 kPag, about 1,400 kPag, or about 1,500 kPag, or within any range defined between any two of the foregoing values, such as about 800 kPag to about 1,500 kPag, about 850 kPag to about 1,400 kPag, about 900 kPag to about 1,300 kPag, about 950 kPag to about 1,200 kPag, about 1,000 kPag to about 1,100 kPag, or about 900 kPag to about 1,100 kPag. Preferably, the separation pressure is about 10 kPag to about 2,000 kPag. More preferably, the separation pressure is about 300 kPag to about 1,500 kPag. Most preferably, the separation pressure is about 600 kPag to about 1,000 kPag.

[0064] The compressed product stream is subjected to single stage flash cooling or distillation to recover liquid and vapor streams. The vapor stream comprises hydrogen and small amounts of hydrogen iodide. The liquid stream is substantially free of hydrogen and comprises hydrogen iodide, residual iodine, and other high boiling materials such as any water. The vapor stream may be recycled to the reactor. The liquid stream is directed to a distillation column for separating the liquid hydrogen iodide in the overhead stream from other high boiling materials including residual iodine and any residual water in the bottoms stream. High boiling materials are taken from the bottoms stream of the distillation column for further processing including iodine recovery and regeneration. A vapor bleed from the overhead of the distillation column may be performed as a purge to remove any non-condensable gases such as hydrogen.

[0065] Alternatively, the product stream may be directed from one or more iodine removal tanks to a heavier distillation column to separate high boiling materials, such as hydrogen iodide and any residual iodine, from low boiling materials, such as unreacted hydrogen. The high boiling materials are directed from the bottoms of the heavy distillation column to an iodine recycle column to separate hydrogen iodide from the residual iodine. The top stream of the heavy column, containing hydrogen and any residual hydrogen iodide, is directed to a product distillation column. The bottoms of the iodine recycle column, containing residual iodine, is recycled to an iodine liquefier. The top stream of the iodine recycle column, containing hydrogen iodide, is directed to a product distillation column to separate hydrogen iodide from hydrogen and other non-condensable gases from the heavy column and the iodine recycle column. The top stream of the product column, containing hydrogen and residual hydrogen iodide, may be recycled to the reactor. The bottoms of the product column contain purified hydrogen iodide.

[0066] In any of the above processes, an additional product column may be added to increase the purity of the hydrogen iodide. The purified hydrogen iodide may be passed through a suitable desiccant to remove any residual moisture before use in a subsequent process, such as, for example, any of the above processes. The purified hydrogen iodide may be provided directly to a subsequent process. Alternatively, or in addition, the purified hydrogen iodide may be collected in a storage tank for short-term storage before use in a subsequent process. Regeneration of iodine and hydrogen results in an efficient process for producing hydrogen iodide.

[0067] The process for producing hydrogen iodide (HI) from hydrogen (H2) and elemental iodine (I2), including using a nickel, cobalt, iron, nickel oxide, cobalt oxide, and / or iron oxide catalyst supported on a support according to the present disclosure, may be a batch process or a continuous process, as described below.

[0068] FIG. 1 is a process flow diagram illustrating an integrated process for producing anhydrous hydrogen iodide. As shown in FIG. 1, the integrated process 10 includes material streams of solid iodine 12 and hydrogen gas 14. Solid iodine 12 may be added continuously or intermittently to a solid storage tank 16. A stream of solid iodine 18 is transferred continuously or intermittently from the solid storage tank 16 by a solids conveying system (not shown) or by gravity to an iodine liquefier 20 where the solid iodine is heated above its melting point but below its boiling point to maintain a level of liquid iodine in the iodine liquefier 20. Although only one liquefier 20 is shown, it is understood that multiple liquefiers 20 may be used in a parallel arrangement. Liquid iodine 22 flows from the iodine liquefier 20 to an iodine evaporator 24. The iodine liquefier 20 may be pressurized with an inert gas to drive the stream of liquid iodine 22. The inert gas may include, for example, nitrogen, argon, or helium, or a mixture thereof. Alternatively, or in addition, the flow of liquid iodine 22 may be driven by a pump (not shown). The flow rate of liquid iodine 22 may be controlled by a liquid flow controller 26. In the iodine vaporizer 24, iodine is heated above its boiling point to form a stream of iodine vapor 28.

[0069] The flow rate of hydrogen 14 may be controlled by a gas flow controller 30. The stream of iodine vapor 28 and the stream of hydrogen 14 are fed to a superheater 36 and heated to a reaction temperature to form a reactant stream 38. The reactant stream 38 is fed to a reactor 40.

[0070] Reactant stream 38 reacts in the presence of catalyst 42 contained within reactor 40 to produce product stream 44. Catalyst 42 may be any of the catalysts described herein. Product stream 44 may include hydrogen iodide, unreacted iodine, unreacted hydrogen, and trace amounts of water and other high boiling impurities.

[0071] The product stream 44 may be provided to an upstream valve 46, which may direct the product stream 44 to an iodine removal step. Alternatively, the product stream 44 may pass through a cooler (not shown) to remove some heat before being directed to the iodine removal step. For iodine removal, the first iodine removal system 48a may include a first iodine removal tank 50a and a second iodine removal tank 50b. The product stream 44 may be cooled in the first iodine removal tank 50a to a temperature below the boiling point of iodine to condense or sublimate at least a portion of the iodine and separate it from the product stream 44. Product stream 44 may be further cooled in a first iodine removal tank 50a to a temperature below the melting point of iodine to separate more iodine from product stream 44 and deposit at least a portion of the iodine as a solid in the first iodine removal tank 50a to produce an iodine-reduced product stream 52. The iodine-reduced product stream 52 may be fed to a second iodine removal tank 50b to be cooled and separate at least a portion of the additional iodine from the iodine-reduced product stream 52 to produce an additional crude hydrogen iodide product stream 54.

[0072] Although the first iodine removal apparatus 48a consists of two iodine removal tanks operating in a series arrangement, it is understood that the first iodine removal apparatus 48a may include two or more iodine removal tanks operating in a parallel arrangement, more than two iodine removal tanks operating in a series arrangement, or any combination thereof. It is also understood that the first iodine removal apparatus 48a may consist of a single iodine removal tank. It is further understood that any of the iodine removal tanks may include or be in the form of a heat exchanger. It is also understood that successive tanks may be combined into a single tank having multiple cooling stages.

[0073] The iodine collected in the first iodine removal vessel 50a may form a first iodine recycle stream 56a. Similarly, the iodine collected in the second iodine removal vessel 50b may form a second iodine recycle stream 56b. Each of the first iodine recycle stream 56a and the second iodine recycle stream 56b may be continuously or intermittently supplied to the iodine liquefaction system 20 as shown, and / or may be supplied to the iodine evaporator 24.

[0074] To provide continuous operation while collecting iodine in solid form, the upstream valve 46 may be configured to selectively direct the product stream 44 to a second iodine removal device 48b, which may be substantially similar to the first iodine removal device 48a described above. Once either the first iodine removal vessel 50a or the second iodine removal vessel 50b of the first iodine removal device 48a has accumulated sufficient solid iodine suitable for removal of the solid iodine, the upstream valve 46 may be selected to direct the product stream 44 from the first iodine removal device 48a to the second iodine removal device 48b. At approximately the same time, a downstream valve 58 configured to selectively direct the crude hydrogen iodide product stream 54 from either the first iodine removal apparatus 48a or the second iodine removal apparatus 48b may be selected to direct the crude hydrogen iodide product stream 54 from the second iodine removal apparatus 48b, such that the process of removing iodine from the product stream 44 to produce the crude hydrogen iodide product stream 54 may continue uninterrupted. Once the product stream 44 is no longer directed to the first iodine removal apparatus 48a, the first iodine removal vessel 50a and the second iodine removal vessel 50b of the first iodine removal apparatus 48a may be heated above the melting point of iodine to liquefy the solid iodine, such that the liquefied iodine may flow through the first iodine recycle stream 56a and the second iodine recycle stream 56b of the first iodine removal apparatus 48a to the iodine liquefaction apparatus 20.

[0075] As the process continues, when either the first iodine removal vessel 50a or the second iodine removal vessel 50b of the second iodine removal apparatus 48b accumulates sufficient solid iodine suitable for removal of the solid iodine, the upstream valve 46 may be selected to direct the product stream 44 from the second iodine removal apparatus 48b back to the first iodine removal apparatus 48a, and the downstream valve 58 may be selected to direct the crude hydrogen iodide product stream 54 from the first iodine removal apparatus 48a, so that the process of removing iodine from the product stream 44 to produce the crude hydrogen iodide product stream 54 may continue uninterrupted. Once product stream 44 is no longer directed to second iodine removal apparatus 48b, first iodine removal vessel 50a and second iodine removal vessel 50b of second iodine removal apparatus 48b may be heated above the melting point of iodine to liquefy solid iodine, which may then flow through first iodine regeneration stream 56a and second iodine regeneration stream 56b of second iodine removal apparatus 48b to iodine liquefaction apparatus 20. By continually switching between first iodine removal apparatus 48a and second iodine removal apparatus 48b, unreacted iodine in product stream 44 may be efficiently and continuously removed and regenerated.

[0076] As described above, liquid iodine may flow through the first and second iodine regeneration streams 56a, 56b of the first and second iodine removal devices 48a, 48b to the iodine liquefaction device 20. Alternatively, liquid iodine may flow through the first and second iodine regeneration streams 56a, 56b of the first and second iodine removal devices 48a, 48b to the iodine evaporator 24, bypassing the iodine liquefaction device 20 and the liquid flow control device 26.

[0077] In the integrated process shown in FIG. 1 , the crude hydrogen iodide product stream 54 is provided to a heavier distillation column 60. The heavier distillation column 60 may be configured for separation of higher boiling materials, such as hydrogen iodide and residual unreacted iodine, from lower boiling materials, such as unreacted hydrogen. A bottoms stream 62 comprising hydrogen iodide and residual unreacted iodine from the heavy distillation column 60 may be provided to an iodine regenerator 64. The iodine regenerator 64 may be configured for separation of residual unreacted iodine from the hydrogen iodide. A bottoms stream 66 from the iodine regenerator 64 comprising unreacted iodine may be returned to the iodine liquefaction system 20 for regeneration. Alternatively, the bottoms stream 66 from the iodine regenerator 64 comprising unreacted iodine may be returned to the iodine liquefaction system 24 for regeneration. A tops stream 68 from the iodine regenerator 64 comprising hydrogen iodide may be provided to a product distillation column 70.

[0078] An overhead stream 72 comprising hydrogen and residual hydrogen iodide from heavy ends column 60 may also be provided to product distillation column 70. Product distillation column 70 may be configured to separate unreacted hydrogen from hydrogen iodide. An overhead stream 74 from product column 70 comprising unreacted hydrogen and residual hydrogen iodide may be returned to reactor 40 for regeneration. The resulting purified hydrogen iodide product may be collected from a bottoms stream 76 from product column 70.

[0079] FIG. 2 is a process flow diagram illustrating another integrated process for producing anhydrous hydrogen iodide. The integrated process 78 shown in FIG. 2 is similar to the integrated process 10 described above with reference to FIG. 1, up to the production of crude hydrogen iodide product stream 54. In the integrated process 78 of FIG. 2, the crude hydrogen iodide product stream 54 is fed to a compressor 80 to increase the pressure of the crude hydrogen iodide product stream 54 to facilitate the recovery of hydrogen and hydrogen iodide. The compressor 80 increases the pressure of the crude hydrogen iodide product stream 54 to a separation pressure greater than the operating pressure of the reactor 42 to produce a compressed product stream 82. The compressed product stream 82 is directed to a partial condenser 84 which is subjected to a single stage flash cooling to separate high boiling materials, such as hydrogen iodide and trace amounts of residual unreacted iodine, from low boiling materials, such as unreacted hydrogen. An overhead stream 86 containing hydrogen and residual hydrogen iodide from the partial condenser 84 may be returned to the reactor 40 for regeneration. A bottoms stream 88 from partial condenser 84 containing hydrogen iodide, traces of residual unreacted iodine, and traces of water may be fed to product column 90. Product column 90 may be configured for separation of residual unreacted iodine, water, and other high boiling compounds from the hydrogen iodide. A bottoms stream 92 from product column 90 containing unreacted iodine may be returned to liquefaction system 20 for regeneration. Alternatively, a bottoms stream 92 from product column 90 containing unreacted iodine may be returned to iodine liquefaction system 24 for regeneration. The resulting purified hydrogen iodide product may be collected from an overhead stream 94 from product column 90. A purge stream 96 may be removed from product column 90 to control the accumulation of low boiling impurities. A portion of purge stream 96 may be returned to reactor 40 for regeneration, while another portion may be discarded.

[0080] While the invention has been described to exemplary designs, the present invention can be further modified within the spirit and scope of the disclosure, and this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains.

[0081] As used herein, the phrase "within any range defined between any two of the preceding values" means that any range may be selected from any two of the values ​​listed preceding such phrase, regardless of whether those values ​​are in the lower portion of the list or in the higher portion of the list. For example, a pair of values ​​may be selected from two lower values, two higher values, or a lower value and a higher value. EXAMPLES

[0082] Example 1: Preparation of hydrogen iodide from hydrogen and iodine catalyzed by nickel catalyst In Example 1, the production of hydrogen iodide (HI) from hydrogen (H2) and elemental iodine (I2) according to Equation 3 above was demonstrated using an alumina supported nickel catalyst over a range of reaction conditions. The catalyst in a fixed bed tubular reactor was activated before introducing a mixture of hydrogen gas and iodine vapor into the reactor. The catalyst was activated by purging the catalyst with nitrogen gas, followed by introduction of hydrogen gas, heating the reactor to 120°C and holding for 2 hours, then increasing the reactor temperature to 230°C and holding for an additional hour. The reactor temperature was then adjusted to the desired reaction temperature. A fixed predetermined flow rate of hydrogen was bubbled into an iodine vaporizer that was initially charged with a predetermined amount of solid elemental iodine. The temperature of the iodine vaporizer was controlled between 150°C and 170°C to generate iodine vapor. The vaporizer temperature and hydrogen flow rate were adjusted accordingly to obtain the desired molar ratio of hydrogen to iodine. A mixture of hydrogen and iodine vapor was fed into the reactor and reacted in the presence of a catalyst to form hydrogen iodide. The reactor effluent was then passed through a two-stage iodine collector to capture any unreacted iodine in solid form. The iodine collector effluent stream containing the crude hydrogen iodide product was then collected in a dry ice trap. The effluent stream from the dry ice trap was bubbled through a scrubber filled with deionized water to capture residual hydrogen iodide from the unreacted hydrogen gas stream. After a period of time, the system was shut down and the weight loss of the iodine vaporizer and the weight gain of the iodine collector were measured to calculate the average H2 / I2 feed molar ratio. The residence time was calculated based on the combined feed rates of hydrogen and iodine, and the conversion was calculated based on the amount of hydrogen iodide collected and iodine fed to the reactor.

[0083] All reactions were run in the range of 0-5 psig. Runs using 21 wt% nickel on alumina support (Ni / Al2O3) catalyst had a run time of 24 hours each. Runs using 20 wt% Ni / Al2O3 or 5 wt% Ni / Al2O3 catalyst had a run time of 72 hours each. Other reaction conditions are shown in Table 1.

[0084] The results of each run are shown in Table 1. As shown in Table 1, when 21 wt. % nickel catalyst was on the alumina support and the contact time was greater than 7 seconds, the average conversion was greater than 90%, and the average productivity was about 35 lb / h / ft for reaction temperatures of about 320° C. to about 360° C. 3 The 20 wt % nickel catalyst on an alumina support performed slightly better than the 21 wt % nickel catalyst on an alumina support under comparable reaction conditions, while the 5 wt % nickel catalyst on an alumina support showed much lower activity. [Table 1] Example 2: Effect of H2 / I2 molar ratio in the preparation of hydrogen iodide from hydrogen and iodine catalyzed by nickel catalyst

[0085] In Example 2, the effectiveness of H2 / I2 molar ratio on HI capture rate was demonstrated over a range of reaction conditions using a 21 wt% Ni / Al2O3 catalyst. The same experimental setup and experimental procedure described in Example 1 was used in Example 2, and each run had a run time of 24 hours. HI capture rate was defined as the percentage of HI captured in the dry ice trap relative to the total HI generated. As shown in Table 2, when the H2 / I2 molar ratio was 2.7 (less than 3), the HI capture rate was over 90%, but increasing the H2 / I2 molar ratio dramatically reduced the HI capture rate. Without being bound by theory, this suggests that in the presence of an excess amount of hydrogen, it becomes more difficult to condense HI. [Table 2] Aspects

[0086] Aspect 1 is a process for producing hydrogen iodide. The process includes providing a gas-phase reactant stream comprising hydrogen and iodine, and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst includes at least one selected from the group of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide. The catalyst is supported on a support.

[0087] Example 2 is the process of Example 1, wherein in the providing step, the hydrogen contains less than about 500 ppm water and less than about 500 ppm oxygen by weight.

[0088] Example 3 is the process of either Example 1 or Example 2, wherein in the providing step, the iodine comprises less than about 500 ppm by weight of water.

[0089] Example 4 is the process of any of Examples 1-3, wherein in the providing step, a molar ratio of hydrogen to iodine in the reactant stream is from about 1:1 to about 10:1.

[0090] Example 5 is the process of Example 4, wherein the molar ratio of hydrogen to iodine is from about 2.5:1 to about 3:1.

[0091] Example 6 is the process of any of Examples 1-5, wherein the support is selected from the group of activated carbon, silica gel, zeolite, silicon carbide, metal oxides, or combinations thereof.

[0092] Example 7 is the process of Example 6, wherein the support is a metal oxide support, the metal oxide support comprising alumina, magnesium oxide, titanium oxide, zinc oxide, zirconia, chromia, and combinations thereof.

[0093] Example 8 is the process of Example 7, wherein the catalyst comprises nickel and the support is alumina.

[0094] Example 9 is the process of any of Examples 1-8, wherein the catalyst is about 0.1% to about 50% by weight of the total weight of the catalyst and support.

[0095] Example 10 is the process of any of Examples 1-9, wherein in the reacting step, the contact time between the reactant stream and the catalyst is from about 0.1 seconds to about 1,800 seconds.

[0096] Example 11 is the process of any of Examples 1-10, further comprising heating the reactant stream to a reaction temperature of from about 150° C. to about 600° C. prior to the reacting step.

[0097] Example 12 is the process of any of Examples 1-11, wherein the product stream further comprises unreacted iodine, and the process further comprises the additional steps of separating the unreacted iodine from the product stream as solid iodine, heating the solid iodine to produce liquid iodine, and returning the liquid iodine to the reactant stream.

[0098] Example 13 is the process of any of Examples 1-12, wherein the process is a continuous process.

[0099] Example 14 is the process of any of Examples 1-13, wherein the product stream further comprises unreacted hydrogen, and the process further comprises the additional steps of separating hydrogen from the product stream and returning the separated hydrogen to the reactant stream.

[0100] Example 15 is the process of example 14, wherein separating the hydrogen from the product stream comprises compressing the product stream and subjecting the compressed product stream to flash cooling.

[0101] A sixteenth aspect is a process for producing hydrogen iodide. The process includes providing a gas-phase reactant stream comprising hydrogen and iodine in a hydrogen to iodine molar ratio of about 1:1 to about 10:1, heating the reactant stream to a reaction temperature of about 150° C. to about 600° C., and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst comprises at least one selected from the group consisting of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide. The catalyst is supported on a support. The catalyst is about 0.1% to about 50% by weight of the total weight of the catalyst and support. The contact time between the reactant stream and the catalyst is about 0.1 seconds to about 1,800 seconds.

[0102] Aspect 17 is a process for producing hydrogen iodide. The process includes providing a gas-phase reactant stream comprising hydrogen and iodine in a hydrogen to iodine molar ratio of about 2:1 to about 5:1, heating the reactant stream to a reaction temperature of about 200° C. to about 500° C., and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst comprises at least one selected from the group of nickel, cobalt, and iron. The catalyst is supported on a support. The catalyst is about 5% to about 45% by weight of the total weight of the catalyst and support. The contact time between the reactant stream and the catalyst is about 2 seconds to about 100 seconds.

[0103] Embodiment 18 is a process for producing hydrogen iodide. The process includes providing a gas-phase reactant stream comprising hydrogen and iodine in a hydrogen to iodine molar ratio of about 2:1 to about 3:1, heating the reactant stream to a reaction temperature of about 300° C. to about 400° C., and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst comprises nickel. The catalyst is supported on a support. The catalyst is about 10% to about 40% by weight of the total weight of the catalyst and support. The contact time between the reactant stream and the catalyst is about 2 seconds to about 60 seconds.

[0104] A nineteenth aspect is a process for producing hydrogen iodide. The process includes providing a gas-phase reactant stream comprising hydrogen and iodine in a hydrogen to iodine molar ratio of about 2.5:1 to about 3:1, heating the reactant stream to a reaction temperature of about 300° C. to about 350° C., and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide. The catalyst comprises nickel. The catalyst is supported on an alumina support. The catalyst is about 15% to about 35% by weight of the total weight of the catalyst and support. The contact time between the reactant stream and the catalyst is about 2 seconds to about 40 seconds.

[0105] Example 20 is the process of any of Examples 16-19, wherein in the providing step, the hydrogen contains less than about 500 ppm water and less than about 500 ppm oxygen by weight, and the iodine contains less than about 500 ppm water by weight.

[0106] Example 21 is the process of any of Examples 16-19, wherein in the providing step, the hydrogen contains less than about 50 ppm by weight of water and less than about 100 ppm of oxygen, and the iodine contains less than about 100 ppm of water.

[0107] Example 22 is the process of any of Examples 16-19, wherein in the providing step, the hydrogen contains less than about 10 ppm water and less than about 10 ppm oxygen by weight, and the iodine contains less than about 30 ppm water.

[0108] Example 23 is the process of any of Examples 16-19, wherein in the providing step, the hydrogen contains less than about 5 ppm water and less than about 1 ppm oxygen by weight, and the iodine contains less than about 10 ppm water.

[0109] Example 24 is the process of any of Examples 16-23, wherein the product stream further comprises unreacted iodine and unreacted hydrogen, the process further comprising the additional steps of separating the unreacted iodine from the product stream as solid iodine, heating the solid iodine to produce liquid iodine, returning the liquid iodine to the reactant stream, separating hydrogen from the product stream by compressing the product stream and subjecting the compressed product stream to flash cooling, and returning the separated hydrogen to the reactant stream, and wherein the process is a continuous process.

[0110] Example 25 is the process of any of Examples 16-23, wherein the product stream further comprises unreacted iodine and unreacted hydrogen, the process further comprising the additional steps of separating the unreacted iodine from the product stream as solid iodine, heating the solid iodine to produce liquid iodine, returning the liquid iodine to the reactant stream, separating hydrogen from the product stream by compressing the product stream and subjecting the compressed product stream to flash cooling, and returning the separated hydrogen to the reactant stream, and wherein the process is a batch process.

[0111] Example 26 is a process for producing hydrogen iodide. The process includes the steps of reacting hydrogen and iodine in the gas phase in the presence of a catalyst to produce a product stream comprising hydrogen iodide and unreacted iodine, the catalyst comprising at least one of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide, the catalyst supported on a support; removing at least a portion of the unreacted iodine from the product stream by cooling the product stream to form solid iodine, the solid iodine being formed in one of a first iodine removal vessel or a second iodine removal vessel; producing liquid iodine from the solid iodine by either heating the first iodine removal vessel to liquefy the solid iodine when the product stream is passed through the second iodine removal vessel and cooled, or by heating the second iodine removal vessel to liquefy the solid iodine when the product stream is passed through the first iodine removal vessel and cooled, and recycling the liquefied iodine to the reaction vessel.

[0112] Example 27 is the process of example 26, wherein the product stream further comprises unreacted hydrogen, and the process further comprises the additional steps of separating hydrogen from the product stream and recycling the separated hydrogen to the reaction step.

[0113] Example 28 is the process of example 27, wherein separating the hydrogen from the product stream comprises compressing the product stream and subjecting the compressed product stream to flash cooling.

[0114] Example 29 is the process of any of Examples 26-28, wherein the process is a continuous process.

[0115] Example 30 is any of the processes of Examples 26-28, wherein the process is a batch process.

[0116] Example 31 is the process of any of Examples 26-30, wherein the support is selected from the group of activated carbon, silica gel, zeolite, silicon carbide, metal oxides, or combinations thereof.

[0117] Example 32 is the process of example 31, wherein the support is a metal oxide support, the metal oxide support comprising alumina, magnesium oxide, titanium oxide, zinc oxide, zirconia, chromia, or a combination thereof.

[0118] Example 33 is the process of Example 32, wherein the catalyst comprises nickel on an alumina support.

[0119] Example 34 is the process of any of Examples 26 to 33, wherein reacting hydrogen with iodine in the vapor phase in the presence of a catalyst is at a reaction temperature of about 150°C to about 600°C.

[0120] Aspect 35 is a process for producing hydrogen iodide, comprising the steps of: reacting hydrogen and iodine in the presence of a catalyst in a gas phase at a molar ratio of hydrogen to iodine of about 1:1 to about 10:1 at a reaction temperature of about 150° C. to about 600° C. and a contact time of about 0.1 seconds to about 1,800 seconds to produce a product stream comprising hydrogen iodide and unreacted iodine, the catalyst comprising at least one of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide, the catalyst being supported on a support, the catalyst being about 0.1% by weight to about 50% by weight of the total weight of the catalyst and support; and cooling the product stream. removing at least a portion of the unreacted iodine from the product stream by passing the solid iodine through a first iodine removal tank to form solid iodine, where the solid iodine is formed in one of the first iodine removal tank or the second iodine removal tank; producing liquid iodine from the solid iodine by either heating the first iodine removal tank to liquefy the solid iodine when the product stream is passed through the second iodine removal tank and cooled, or by heating the second iodine removal tank to liquefy the solid iodine when the product stream is passed through the first iodine removal tank and cooled; and recycling the liquefied iodine to the reaction step.

[0121] Aspect 36 is a process for producing hydrogen iodide, comprising the steps of: reacting hydrogen and iodine in the presence of a catalyst in the vapor phase at a hydrogen to iodine molar ratio of about 2:1 to about 5:1, a reaction temperature of about 200° C. to about 500° C., and a contact time of about 2 seconds to about 100 seconds to produce a product stream comprising hydrogen iodide and unreacted iodine, the catalyst comprising at least one of nickel, cobalt, and iron, the catalyst being supported on a support, the catalyst being about 5% to about 45% by weight of the total weight of the catalyst and support, and cooling the product stream to form solid iodine. removing at least a portion of the unreacted iodine from the product stream by, where solid iodine is formed in one of the first iodine removal tank or the second iodine removal tank; producing liquid iodine from the solid iodine by either heating the first iodine removal tank to liquefy the solid iodine when the product stream is passed through the second iodine removal tank and cooled, or by heating the second iodine removal tank to liquefy the solid iodine when the product stream is passed through the first iodine removal tank and cooled; and recycling the liquefied iodine to the reaction step.

[0122] Aspect 37 is a process for producing hydrogen iodide, comprising the steps of: reacting hydrogen and iodine in the presence of a catalyst in the vapor phase at a molar ratio of hydrogen to iodine of about 2:1 to about 3:1, a reaction temperature of about 300° C. to about 400° C., and a contact time of about 2 seconds to about 60 seconds to produce a product stream comprising hydrogen iodide and unreacted iodine, wherein the catalyst comprises nickel, the catalyst is supported on a support, and the catalyst is about 10% by weight to about 40% by weight of the total weight of the catalyst and support; and removing solid iodine from the product stream by cooling the product stream to form solid iodine. removing at least a portion of the unreacted iodine, where solid iodine is formed in one of the first iodine removal tank or the second iodine removal tank; producing liquid iodine from the solid iodine by either heating the first iodine removal tank to liquefy the solid iodine when the product stream is passed through the second iodine removal tank and cooled, or by heating the second iodine removal tank to liquefy the solid iodine when the product stream is passed through the first iodine removal tank and cooled; and recycling the liquefied iodine to the reaction step.

[0123] Embodiment 38 is a process for producing hydrogen iodide. The process includes the steps of: reacting hydrogen and iodine in the presence of a catalyst in the vapor phase at a molar ratio of hydrogen to iodine of about 2.5:1 to about 3:1, a reaction temperature of about 300° C. to about 350° C., and a contact time of about 2 seconds to about 40 seconds to produce a product stream comprising hydrogen iodide and unreacted iodine, the catalyst comprising nickel on an alumina support, the catalyst being supported on the support, the catalyst being about 15% by weight to about 35% by weight of the total weight of the catalyst and support; and cooling the product stream to form solid iodine. removing at least a portion of the unreacted iodine from the product stream, where solid iodine is formed in one of the first iodine removal tank or the second iodine removal tank; producing liquid iodine from the solid iodine by either heating the first iodine removal tank to liquefy the solid iodine when the product stream is passed through the second iodine removal tank and cooled, or by heating the second iodine removal tank to liquefy the solid iodine when the product stream is passed through the first iodine removal tank and cooled; and recycling the liquefied iodine to the reaction step.

[0124] Example 39 is the process of any of Examples 35-38, wherein the product stream further comprises unreacted hydrogen, and the process further comprises the additional steps of separating hydrogen from the product stream by compressing the product stream and subjecting the compressed product stream to flash cooling, and recycling the separated hydrogen to the reaction step, and wherein the process is a continuous process.

[0125] Example 40 is the process of any of Examples 35-39, wherein the product stream further comprises unreacted hydrogen, and the process further comprises the additional steps of separating hydrogen from the product stream by compressing the product stream and subjecting the compressed product stream to flash cooling, and recycling the separated hydrogen to the reaction step, and wherein the process is a batch process.

[0126] Example 41 is the process of any of Examples 35-40, wherein the hydrogen contains less than about 500 ppm water and less than about 500 ppm oxygen by weight, and the iodine contains less than about 500 ppm water.

[0127] Example 42 is the process of any of Examples 35-41, wherein the hydrogen contains less than about 50 ppm by weight of water and less than about 100 ppm of oxygen, and the iodine contains less than about 100 ppm of water.

[0128] Example 43 is the process of any of Examples 35-42, wherein the hydrogen contains less than about 10 ppm water and less than about 10 ppm oxygen by weight, and the iodine contains less than about 30 ppm water.

[0129] Example 44 is the process of any of Examples 35-43, wherein the hydrogen contains less than about 5 ppm water and less than about 1 ppm oxygen by weight, and the iodine contains less than about 10 ppm water. The present invention includes the following aspects. [1] 1. A process for producing hydrogen iodide comprising the steps of: providing a gas phase reactant stream comprising hydrogen and iodine; and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide, the catalyst comprising at least one selected from the group of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide, the catalyst being supported on a support. [2] 2. The process of claim 1, wherein in the providing step, the hydrogen contains less than about 500 ppm by weight of water and less than about 500 ppm by weight of oxygen. [3] The process of [1], wherein in the providing step, the iodine contains less than about 500 ppm by weight of water. [4] The process of [1], wherein in the providing step, a molar ratio of the hydrogen to the iodine in the reactant stream is from about 1:1 to about 10:1. [5] 2. The process of claim 1, wherein the support is selected from the group consisting of activated carbon, silica gel, zeolite, silicon carbide, metal oxides, or combinations thereof. [6] 5. The process of claim 1, wherein the support is a metal oxide support, the metal oxide support comprising alumina, magnesium oxide, titanium oxide, zinc oxide, zirconia, chromia, and combinations thereof. [7] [6] The process according to [6], wherein the catalyst comprises nickel and the support is alumina. [8] The product stream further comprises unreacted iodine, and the process further comprises adding an additional separating the unreacted iodine from the product stream as solid iodine; heating the solid iodine to produce liquid iodine; and returning the liquid iodine to the reactant stream. [9] The product stream further comprises unreacted hydrogen, and the process further comprises: separating the hydrogen from the product stream; and returning the separated hydrogen to the reactant stream.

[10] Separating the hydrogen from the product stream compressing the product stream; and flash cooling the compressed product stream.

Claims

1. 1. A process for producing hydrogen iodide comprising the steps of: providing a gas phase reactant stream comprising hydrogen and iodine; and reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide, the catalyst comprising at least one selected from the group of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide, the catalyst being supported on a support.

2. providing a gas phase reactant stream comprising hydrogen and iodine; 1. A process for producing hydrogen iodide comprising: reacting the reactant stream in the presence of a catalyst to produce a product stream comprising hydrogen iodide, the catalyst comprising at least one selected from the group of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide, the catalyst being supported on a support; The product stream further comprises unreacted iodine and unreacted hydrogen, and the process further comprises: separating the unreacted iodine from the product stream as solid iodine; heating the solid iodine to produce liquid iodine; returning the liquid iodine to the reactant stream; Separating the hydrogen from the product stream, the step of separating the hydrogen from the product stream comprising: compressing the product stream; flash cooling the compressed product stream; and returning said separated hydrogen to said reactant stream.

3. 1. A process for producing hydrogen iodide comprising the steps of: reacting hydrogen and iodine in the vapor phase in the presence of a catalyst to produce a product stream comprising hydrogen iodide and unreacted iodine, the catalyst comprising at least one selected from the group consisting of nickel, cobalt, iron, nickel oxide, cobalt oxide, and iron oxide, the catalyst being supported on a support; removing at least a portion of the unreacted iodine from the product stream by cooling the product stream to form solid iodine, the solid iodine comprising: a first iodine removal vessel; or removing at least a portion of the unreacted iodine from the product stream formed in one of the second iodine removal vessels; A step of producing liquid iodine from the solid iodine, by heating the first iodine removal vessel to liquefy the solid iodine when the product stream is cooled through the second iodine removal vessel; or producing liquid iodine from the solid iodine by heating the second iodine removal vessel to liquefy the solid iodine when the product stream through the first iodine removal vessel is cooled; and recovering said liquid iodine to produce a product stream comprising said hydrogen iodide and unreacted iodine.

4. 2. The process of claim 1, wherein the hydrogen contains less than 500 ppm by weight of water and less than 500 ppm by weight of oxygen.

5. 2. The process of claim 1, wherein the iodine contains less than 500 ppm by weight of water.

6. 2. The process of claim 1, wherein the molar ratio of said hydrogen to said iodine in said reactant stream is from 1:1 to 10:

1.

7. 7. The process of claim 6, wherein the molar ratio of said hydrogen to said iodine in the reactant stream is from 2.5:1 to 3:

1.

8. 2. The process of claim 1, wherein the support is selected from the group consisting of activated carbon, silica gel, zeolites, silicon carbide, metal oxides, or combinations thereof.

9. 9. The process of claim 8, wherein the support is a metal oxide support, the metal oxide support being selected from the group consisting of alumina, magnesium oxide, titanium oxide, zinc oxide, zirconia, chromia, and combinations thereof.

10. 7. The process of claim 6 wherein the catalyst is nickel and the support is alumina.

11. 2. The process of claim 1, wherein the weight percentage of the catalyst as a percentage of the total weight of the catalyst and the support is from 0.1% to 50% by weight.

12. 2. The process of claim 1, wherein the contact time between the reactant stream and the catalyst is from 0.1 seconds to 1,800 seconds.

13. 10. The process of claim 1, further comprising heating a reactant stream to a reaction temperature of from 150° C. to 600° C. prior to producing the product stream comprising hydrogen iodide.

14. The product stream further comprises unreacted hydrogen, and the process further comprises: separating the hydrogen from the product stream; 4. The process of claim 3, further comprising returning the separated hydrogen to the process for producing a product stream comprising the hydrogen iodide and unreacted iodine.

15. Separating the hydrogen from the product stream compressing the product stream; and flash cooling the compressed product stream.

16. The process of claim 3 , wherein the process is a continuous process.

17. 4. The process of claim 3, wherein the support is selected from the group consisting of activated carbon, silica gel, zeolites, silicon carbide, metal oxides, or combinations thereof.

18. 18. The process of claim 17, wherein the support is a metal oxide support, the metal oxide support being selected from the group consisting of alumina, magnesium oxide, titanium oxide, zinc oxide, zirconia, chromia, and combinations thereof.

19. 4. The process of claim 3, wherein reacting hydrogen with iodine in the gas phase in the presence of a catalyst is carried out at a reaction temperature of from 150°C to 600°C.

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