Improved process for producing ammonia

Abstract

The present invention relates to an improved method for the low-cost, low-carbon production of ammonia. In particular, the present invention relates to a process for the production of ammonia comprising contacting a hydrogen feedstock with a MAB phase catalyst in the presence of nitrogen in a thermal reactor.

Description

IMPROVED PROCESS FOR PRODUCING AMMONIARELATED APPLICATION

[0001] The present application claims priority from Australian Patent Application No.2025901028, filed on 28 March 2025, the entire contents of which is incorporated herein by reference.FIELD OF THE INVENTION

[0002] The present invention relates to the field of ammonia production. In particular, the invention relates to an improved process for the low-cost, low-carbon production of ammonia. However, it will be appreciated that the invention is not limited to this particular field of use.BACKGROUND OF THE INVENTION

[0003] The following discussion of the prior art is provided to place the invention in an appropriate technical context and enable the advantages of it to be more fully understood. It should be appreciated, however, that any discussion of the prior art throughout the specification should not be considered as an express or implied admission that such prior art is widely known or forms part of the common general knowledge in the field.

[0004] Ammonia (NH3) is an important compound that is used in industrial productions, pharmaceuticals, synthetic fibers and fertilizer production. In fact, ammonia is the second most produced chemical in the world, contributing ~2% of all global greenhouse gas (GHG) emissions and consuming ~2% of global energy during its production.

[0005] Current methods for producing ammonia include the Haber-Bosch process, which requires high temperature and pressure to reduce N2 to NH3 within coal-based or natural gasbased ammonia plants. The Haber-Bosch process requires harsh reaction conditions such as high temperatures and pressures, and reliance on the use of fossil fuels as the hydrogen source to produce ammonia, leading to large energy consumption and excessive GHG emissions.

[0006] Decarbonizing this hard-to-abate sector has limited options. Current large-scale methods include the replacement of fossil fuel feedstocks with green or low-carbon hydrogen, mainly produced by electrolysers powered by renewable electricity. Carbon capture, utilization and storage (CCUS) systems are also being developed to capture carbon dioxide so that it is not emitted into the atmosphere. Finally, ammonia plants that transform the ammonia into nitrates for fertilizers or explosives have started employing NOXand N2O decomposition catalysts to reduce those emissions, which have a large overall Global Warming Potential (GWP). Each of these options has a significantly high Capex and / or Opex cost, greatly increasing the levelized cost ofammonia. Therefore, successful market adoption relies on the increased levelized cost of ammonia being offset by regulatory incentives or penalties (carbon taxes, credits, etc.)

[0007] Accordingly, there exists a need for an improved process to produce ammonia that is low-cost and has reduced GHG emissions.

[0008] It is an object of the present invention to overcome or ameliorate one or more of the disadvantages of the prior art, or at least to provide a useful alternative.SUMMARY OF THE INVENTION

[0009] According to a first aspect, the present invention provides a process for the production of ammonia comprising contacting a hydrogen feedstock with a MAB phase catalyst in the presence of nitrogen in a thermal chemical reactor.

[0010] In one embodiment, the hydrogen feedstock comprises water.

[0011] Accordingly, in another aspect of the invention there is provided a process for the production of ammonia comprising contacting water with a MAB phase catalyst in the presence of nitrogen in a thermal chemical reactor.

[0012] In another embodiment, the hydrogen feedstock comprises hydrogen gas.

[0013] In one embodiment, nitrogen is present in the form of air.

[0014] In one embodiment of the invention, the MAB phase catalyst is selected from the group consisting of MoAIB, WAIB, Fe2AIB2, Mn2AIB2, Cr2AIB2, Cr3AlB4, Cr4AlB4, Cr4AlB6, and combinations thereof.

[0015] In another embodiment, the MAB phase catalyst may comprise a combination of transition metal species, and may be defined by the following formulae: (MoaWbFecMndCre)AIB, or (MoaWbFecMndCre)2AIB2, or (MoaWbFecMndCre)3AIB4, or (MoaWbFecMndCre)4AIB4, or (MoaWbFecMndCre)4AIB6, whereby 0 < a < 1, 0 < b < 1, 0 < c < 1, 0 < d < 1, 0 < e < 1, and a + b + c + d + e = 1.

[0016] A further aspect of the invention provides ammonia produced by the process of the invention.

[0017] These and other aspects of the present invention will be more apparent to the skilled addressee upon reading the following detailed description in connection with the accompanying examples and claims.DEFINITIONS

[0018] In describing and claiming the present invention, the following terminology will be used in accordance with the definitions set out below. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only and is not intended to be limiting.

[0019] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one having ordinary skill in the art to which the invention pertains.

[0020] Unless the context clearly requires otherwise, throughout the description and the claims, the terms “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”. For example, a composition, mixture, process or method that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, mixture, process or method.

[0021] The transitional phrase “consisting of’ excludes any element, step, or ingredient not specified. If in the claim, such would close the claim to the inclusion of materials other than those recited except for impurities ordinarily associated therewith. When the phrase “consisting of” appears in a clause of the body of a claim, rather than immediately following the preamble, it limits only the element set forth in that clause; other elements are not excluded from the claim as a whole.

[0022] The transitional phrase “consisting essentially of” is used to define a composition, process or method that includes materials, steps, features, components, or elements, in addition to those literally disclosed, provided that these additional materials, steps, features, components, or elements do not materially affect the basic and novel characteristic(s) of the claimed invention. The term “consisting essentially of” occupies a middle ground between "comprising" and “consisting of”.

[0023] Where the applicant has defined an invention or a portion thereof with an open-ended term such as "comprising", it should be readily understood that (unless otherwise stated) the description should be interpreted to also describe such an invention using the terms "consisting essentially of" or "consisting of." In other words, with respect to the terms “comprising”, “consisting of”, and “consisting essentially of’, where one of these three terms is used herein, the presently disclosed and claimed subject matter may include the use of either of the other two terms. Thus, in some embodiments not otherwise explicitly recited, any instance of “comprising” may be replaced by “consisting of” or, alternatively, by “consisting essentially of”.

[0024] While reference may be made in this disclosure to the invention comprising a combination of a plurality of elements, it is also understood that this invention is regarded to comprise combinations which omit or exclude one or more of such elements, even if this omission or exclusion of an element or elements is not expressly stated herein, unless it is expressly stated herein that an element is essential to the applicant' s combination and cannot be omitted. It is further understood that the related prior art may include elements from which this invention may be distinguished by negative claim limitations, even without any express statement of such negative limitations herein. It is to be understood, between the positive statements of applicant's invention expressly stated herein, and the prior art and knowledge of the prior art by those of ordinary skill which is incorporated herein even if not expressly reproduced here for reasons of economy, that any and all such negative claim limitations supported by the prior art are also considered to be within the scope of this disclosure and its associated claims, even absent any express statement herein about any particular negative claim limitations.

[0025] As used herein, with reference to numbers in a range of numerals, the terms "about," "approximately" and "substantially" are understood to refer to the range of -10% to +10% of the referenced number, preferably -5% to +5% of the referenced number, more preferably -1 % to + 1 % of the referenced number, most preferably -0.1 % to +0.1 % of the referenced number. Moreover, with reference to numerical ranges, these terms should be construed as providing support for a claim directed to any number or subset of numbers in that range. For example, a disclosure of from 1 to 10 should be construed as supporting a range of from 1 to 8, from 3 to 7, from 1 to 9, from 3.6 to 4.6, from 3.5 to 9.9, from 8 to 10, and so forth.

[0026] The terms “preferred” and “preferably” refer to embodiments of the invention that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

[0027] The complete disclosures of the patents, patent documents and publications cited herein are incorporated by reference in their entirety as if each were individually incorporated.

[0028] Unless expressly stated to the contrary, "or" refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).

[0029] The term "and / or" used in the context of " X and / or Y" should be interpreted as " X," or " Y," or " X and Y." Similarly, "at least one of X or Y" should be interpreted as " X," or " Y," or "both X and Y."

[0030] The indefinite articles "a" and "an" preceding an element or component of the invention are intended to be non-restrictive regarding the number of instances (i.e., occurrences) of the element or component. Therefore "a" or "an" should be read to include one or at least one, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular.

[0031] It will be understood that use of the term “between” herein when referring to a range of numerical values encompasses the numerical values at each endpoint of the range. For example, a temperature of between 80 °C and 150 °C is inclusive of a temperature of 80 °C and a temperature of 150 °C.

[0032] Various features of the embodiments of the invention disclosed herein are, for brevity, described in the context of a single embodiment, but may also be provided separately or in any suitable sub-combination. All combinations of the embodiments are specifically embraced by the illustrative embodiments disclosed herein just as if each and every combination was individually and explicitly disclosed. In addition, all sub-combinations listed in the embodiments describing such variables are also specifically embraced by the present compositions and are disclosed herein just as if each and every such sub-combination was individually and explicitly disclosed herein.

[0033] In the foregoing paragraphs, where various ratios of components have been disclosed. It will be appreciated that these ratios of components can be combined in any disclosed combination. For example, the ratio of A: B (which may be between about 100:1 and 1:100 or any range therein), may be combined with the ratio of C: D (which may be between about 50:1 and 1:50 or any range therein), and may be combined with the ratio of E: F (which may be between about 10:1 and about 1:10 or any range therein).BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The aspects described above, as well as other apparent aspects, advantages, and objectives of the present invention are apparent from the detailed description below in combination with the drawing, in which:

[0035] Figure 1 illustrates the atomic structure of various MAB phases.

[0036] Figure 2 illustrates schematic diagrams of analytic setups for FTIR analysis of ammonia produced by catalysts under ambient conditions: (a) gas flow reaction, and (b) gasliquid reaction.

[0037] Figure 3 is a graphical representation of normalized FTIR spectra of ammonia produced by different MAB phase catalysts using ambient (humid) air as the gas feedstock. Background ppm = 0, Fe2AIB2 ppm ~ 1, MoAIB ppm ~ 1, Mn2AIB2 ppm ~ 1, Cr2AlB2 ppm = 6.

[0038] Figure 4 shows the impact of N2 vs air feedstock on ammonia production using a Cr2AIB2 catalyst. N2 feedstock: ppm = 6.

[0039] Figure 5 shows the effects of bubbling ambient (humid) air through a water trap to increase water vapor addition in the gas feedstock delivered to the Cr2AIB2 catalyst.

[0040] Figure 6 illustrates ammonia produced during a saturator experiment, with air bubbled through the Cr2AIB2 catalyst submerged in water, obtaining 12 ppm ammonia.

[0041] Figure 7 is a graphical representation or ammonia produced using a Cr2AIB2 catalyst submerged in water with air bubbled through at different flow rates, with minutes representing time to fill a 1.33 L multi-pass cell.

[0042] Figure 8 is a graphical representation of the increase in pH of water due to ammonia production from Cr2AIB2 catalyst submerged in water with air continuously bubbled through the water.

[0043] Figure 9 illustrates a schematic of a thermal ammonia reactor setup.

[0044] Figure 10 shows rates of ammonia production using a thermal reactor at different operating conditions.

[0045] Figure 11 is a graphical representation of rates of ammonia production from control experiments in a thermal reactor using either an inert material (SiC) in place of the catalyst, or the Cr2AIB2 catalyst.

[0046] Figure 12 illustrates a miniaturised thermal reactor for isotope-labelled feedstock testing.

[0047] Figure 13 shows NMR spectra for aqueous ammonia samples produced using N2 + O2 + H2O (N2: O2 = 50:50) in the miniature thermal reactor using14N2 and15N2 gas sources.

[0048] Figure 14 shows GC-MS analysis of the product gases obtained from the N2 + O2 + H2O experiments using 15N2 and 14N2 in the miniature thermal ammonia reactor.DETAILED DESCRIPTION

[0049] The skilled addressee will understand that the invention comprises the embodiments and features disclosed herein as well as all combinations and / or permutations of the disclosed embodiments and features.

[0050] The present inventors discovered that a niche family of compounds known as “MAB phases” have properties that enable them to act as effective catalysts for the synthesis of ammonia. Advantageously, the process of the invention may be used as a direct replacement for Haber-Bosch catalysts, enabling their use in current ammonia plants while reducing carbon emissions. The process of the invention may also be performed in a modified ammonia plant that uses water and air as feedstocks, thereby further reducing GHG emissions.

[0051] In one aspect, the present invention provides a process for the production of ammonia comprising contacting a hydrogen feedstock with a MAB phase catalyst in the presence of nitrogen in a thermal chemical reactor.

[0052] The term “MAB phase catalyst” or “MAB phase catalysts” as used herein refers to ternary transition metal aluminium borides (MAB) where “M” is selected from Mo, Fe, Mn, Cr, or W; A is aluminium; and B is boron. Examples of MAB phase catalysts include MoAIB, WAIB, Fe2AIB2, Mn2AIB2, Cr2AIB2, Cr3AlB4, Cr4AlB4 and Cr4AlB6. The catalysts consist of a selfassembling nano-layered structure displaying alternating layers of transition metal boride (MB) slabs and planes of aluminium atoms as illustrated in Figure 1.

[0053] The process of the invention uses hydrogen and nitrogen as a feedstock and a MAB phase catalyst to produce ammonia.

[0054] In one embodiment, the hydrogen feedstock comprises hydrogen gas.

[0055] In another embodiment, the hydrogen feedstock comprises water. As used herein the term “water” will be understood to refer to liquid water as well as steam or water vapor. In one embodiment, the water is contacted with a MAB phase catalyst as steam. In another embodiment, the water is contacted with a MAB phase catalyst as water vapor. In a further embodiment, water is contacted with a MAB phase catalyst as liquid water.

[0056] In one embodiment, nitrogen is present in the form of air. As used herein the term “air” will be understood to mean the mixture of gases including oxygen and nitrogen forming the earth’s atmosphere. The air may be at atmospheric pressure or may be compressed to a higher pressure.

[0057] In another embodiment, nitrogen is present as nitrogen gas.

[0058] In one embodiment, the hydrogen feedstock is mixed with air prior to being contacted with a MAB phase catalyst. In a preferred embodiment, the hydrogen feedstock is mixed with compressed air prior to being contacted with a MAB phase catalyst.

[0059] In one embodiment, the hydrogen feedstock is mixed with nitrogen gas prior to being contacted with a MAB phase catalyst.

[0060] In one or more embodiments, the MAB phase catalyst is selected from the group consisting of MoAIB, WAIB, Fe2AIB2, Mn2AIB2, Cr2AIB2, Cr3AlB4, Cr4AlB4, Cr4AlB6, and combinations thereof. In a preferred embodiment, the MAB phase catalyst is Cr2AIB2.

[0061] In another embodiment, the MAB phase catalyst may comprise a combination of transition metal species, and may be defined by the following formulae: (MoaWbFecMndCre)AIB, or (MoaWbFecMndCre)2AIB2, or (MoaWbFecMndCre)3AIB4, or (MoaWbFecMndCre)4AIB4, or (MoaWbFecMndCre)4AIB6, whereby 0 < a < 1, 0 < b < 1, 0 < c < 1, 0 < d < 1, 0 < e < 1, and a + b + c + d + e = 1.

[0062] Without wishing to be bound by theory, it is believed that the process of the invention proceeds by adsorbing nitrogen from the air and extracting hydrogen from the water. This implies two separate reactions occurring at the surface of the material simultaneously: 1) water splitting (2H2O — > 2H2 + O2, or H2O — > H++ OH-) and 2) nitrogen reduction (N2 — > 2N). The products of the two reactions combine on the catalyst surface to form ammonia (NH3). Both reactions are typically very energy intensive in an industrial context, water splitting due to the overall energy input required and nitrogen reduction due to the high activation energy required. While separate catalysts exist for water splitting and for nitrogen reduction, there are few which can perform both concurrently, which is necessary for ammonia production directly from air and water. Further, those which can perform both reactions concurrently rely on a way to remove oxygen from the water such as by adding an oxygen scavenger or by physical separation (membrane, filter, etc.) to avoid catalyst poisoning. Those additions are not needed for the process of the invention, as MAB phase catalysts are shown to resist oxygen poisoning, which is a significant issue for most ammonia catalysts.

[0063] Without wishing to be bound by theory, it is observed that while the MAB phase catalysts facilitate the production of ammonia from air and water, the binary metal borides (MBs), e.g. CrB, MoB, FeB, MnB, WB, are believed to react with water to produce a gas, but not ammonia. It is believed that the MBs act specifically to produce hydrogen from water. For this reason, it is suspected that the MB layers within the MAB phase are the active portion of the catalyst responsible for the production of hydrogen, and the aluminium layers (or the interaction between the aluminium and MB layers) are the active portion of the catalyst responsible for thenitrogen reduction. Because these active zones are separated by a thickness of only 1 or 2 atoms, it is theorized to be incredibly easy for the adsorbed hydrogen and nitrogen to react together and form ammonia.

[0064] MAB phase catalysts have different properties that may make one more suitable than the others in certain circumstances. As an example, Fe2AlB2 is cheaper to produce but degrades over time from being in contact with water. On the other hand, MoAIB is more costly to produce due to the price of the transition metal, but does not degrade, or degrades only by an imperceptible amount, at least at temperatures less than around 360 °C.

[0065] Cr2AIB2 is a promising MAB phase catalyst for use as a catalyst in the process of the invention due to its ease of synthesis, relatively low-cost starting materials and resistance to degradation in the presence of air and / or water. Further, Cr2AIB2 has been shown to have a high rate of production of ammonia.

[0066] The process of the invention removes the need for steam-methane reformation (SMR) and removes the need to electrolyze the water, thereby lowering the levelized cost of production.

[0067] In one aspect, the present invention provides a process for the production of ammonia comprising contacting water with a MAB phase catalyst in the presence of nitrogen in a thermal chemical reactor, wherein the process is not an electrocatalytic process.

[0068] Importantly, MAB phase catalysts such as Cr2AIB2 are shown to be resistant to poisoning by water and oxygen. This further reduces Capex and Opex costs because in typical ammonia plants, significant engineering systems are required to ensure any poisoning agents such as oxygen and water (and chlorine and sulphur) are removed from the feedstock stream before reaching the ammonia synthesis catalyst, including via methods which consume additional hydrogen and therefore more fossil fuel. The poison-tolerant nature of the MAB phase catalysts may allow for the production of ammonia without an air separation unit, which is usually needed to extract nitrogen from the air to form part of the feedstock.

[0069] Additionally, MAB phase catalysts such as Cr2AIB2 have been shown to resist oxidation and other forms of degradation up until temperatures greater than 700 °C, making them excellent candidates for the direct replacement of Haber-Bosch ammonia synthesis catalysts.

[0070] As mentioned, one of the advantages of the process of the invention is that it may be adapted for use in existing ammonia producing plants and thermal chemical reactors, with the MAB phase catalysts directly replacing Haber-Bosch ammonia synthesis catalysts.

[0071] The skilled addressee will understand that a thermal chemical reactor is an enclosed volume such as a tank, pipe or tube within which chemical reactions take place. A thermalchemical reactor may be operated at increased pressure and / or temperature. In some embodiments, the thermal chemical reactor is a continuous flow reactor.

[0072] In one embodiment, the thermal chemical reactor is operated at room temperature and pressure, about 20 °C and about 0.1 MPa.

[0073] In one or more embodiments, the reaction is performed at an elevated temperature of between about 30 °C and about 650 °C, for example, about 30 °C, about 40 °C, about 50 °C, about 60 °C, about 70 °C, about 80 °C, about 90 °C, about 100 °C, about 110 °C, about 120 °C, about 130 °C, about 140 °C, about 150 °C, about 160 °C, about 170 °C, about 180 °C, about 190 °C, about 200 °C, about 210 °C, about 220 °C, about 230 °C, about 240 °C, about 250 °C, about 260 °C, about 270 °C, about 280 °C, about 290 °C, about 300 °C, about 310 °C about 320 °C, about 330 °C about 340 °C, about 350 °C about 360 °C, about 370 °C about 380 °C, about 390 °C about 400 °C, about 410 °C, about 420 °C, about 430 °C, about 440 °C, about 450 °C, about 460 °C, about 470 °C about 480 °C, about 490 °C, about 500 °C, about 510 °C, about 520 °C, about 530 °C, about 540 °C, about 550 °C, about 560 °C, about 570 °C, about 580 °C, about 590 °C, about 600 °C, about 610 °C, about 620 °C, about 630 °C, about 640 °C or about 650 °C. In a preferred embodiment, the reaction is performed at about 500 °C.

[0074] In one or more embodiments, the reaction is performed at an elevated pressure of between about 0.25 MPa to about 25 MPa, for example, at a pressure of about 0.25 MPa, about 0.3 MPa, about 0.35 MPa, about 0.4 MPa, about 0.45 MPa, about 0.5 MPa, about 0.55 MPA, about 0.6 MPa, about 0.65 MPa, about 0.7 MPa, about 0.75 MPa, about 0.8 MPa, about 0.85 MPa, about 0.9 MPa, about 0.95 MPa, about 1 MPa, about 2 MPa, about 3 MPa, about 4 MPa, about 5 MPa, about 6 MPa, about 7 MPa, about 8 MPa, about 9 MPa, about 10 MPa, about 11 MPa, about 12 MPA, about 13 MPa, about 14 MPa, about 15 MPa, about 16 MPa, about 17 MPa, about 18 MPa, about 19 MPa, about 20 MPa, about 21 MPa, about 22 MPa, about 23 MPa, about 24 MPa, or about 25 MPa.

[0075] The process of the invention further includes collecting ammonia from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor. In one embodiment, the ammonia is collected by cooling the gases produced in the thermal chemical reactor, allowing the ammonia to condense and be collected as a liquid. In some embodiments, the gases produced in the thermal chemical reactor are cooled to a temperature of between about -15 °C to about -25 °C, for example, about -15 °C, about -16 °C, about -17 °C, about -18 °C, about -19 °C, about -20 °C, about -21 °C, about -22 °C, about -23 °C, about -24 °C, or about -25 °C.

[0076] In one embodiment, wherein the hydrogen feedstock comprises water, the ammonia is absorbed by unreacted water feedstock in an ammonia converter and subsequently separated and stored as liquid ammonia. In a further embodiment, the aqueous ammonia solution produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst is stored ambiently as a liquid.

[0077] In another embodiment, the ammonia is collected by separating gaseous ammonia from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.

[0078] In yet another embodiment wherein the hydrogen feedstock comprises steam, the ammonia is separated from the gas stream produced by contacting the steam and nitrogen with the MAB phase catalyst in the thermal chemical reactor before condensing the steam.

[0079] In one or more embodiments, the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst are cooled under increased pressure, at about 0.1 MPa to about 2 MPa.

[0080] In one embodiment, the process according to the invention further includes the step of collecting or re-circulating unreacted hydrogen from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.

[0081] In one embodiment, the process according to the invention further includes the step of collecting or re-circulating unreacted nitrogen from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.

[0082] In one embodiment, the process according to the invention further includes the step of collecting oxygen from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.

[0083] In one embodiment, the process according to the invention further includes separation of other unwanted product gases for purging from the system.EXAMPLES

[0084] The present invention will now be described with reference to the following examples, which should be considered in all respects as illustrative and non-restrictive.EXAMPLE 1. Methods for preparing MAB Phase catalysts1.1 Tube Furnace

[0085] MAB Phase catalysts may be prepared with high-purity and in a reproducible manner via a solid-state reaction in a tube furnace. The catalysts may be prepared in either a single-step process or a two-step process. For the single-step process, elemental metal powders (Cr, Mo, Fe, Mn or W) are mixed with aluminium and boron in the defined molar ratio outlined below in Table 1. The powders are then pressed into a pellet, placed into a silica or alumina tube furnace, heated to a prescribed temperature for a prescribed period of time under an inert atmosphere or vacuum condition and then cooled. The resultant material is crushed and analysed to confirm the MAB phase composition. Typically, the single-step process results in samples with slightly lower purity than the two-step process.

[0086] For the two-step process, elemental metal powders (Cr, Mo, Fe, Mn or W) are first mixed with boron in a defined molar ratio as outlined in Table 1. As above, the samples are pressed and fired in a tube furnace to obtain a binary metal boride compound. This metal boride material is then mixed with aluminium in a defined molar ratio, pressed, fired, and analysed to confirm the MAB phase composition. Alternatively, the powder mixtures are not pressed into a pellet but simply fired as loose or loosely packed powder. The powder mixture is mixed before loading into the furnace by shaking the powders either by hand in a jar containing plastic balls or in a milling vial and subjected to high-energy ball milling in a shaker mill. The milling vial and balls are both made from hardened steel, and charge ratio (ball to powder mass ratio) of 5-10 is used. An inert gas is used to displace the air in the tube prior to and during synthesis. Alternatively, vacuum may be used to remove the air from within the tube during synthesis. The resulting product can range in form, from a powder to a porous solid to a solid pellet. However, it is noted that the ‘solid pellet’ in this method rarely exceeds about 75% of its theoretical maximum density - i.e. it is still porous. The two-step process yields better purity than the single-step process for most MAB phase catalysts. One exception is WAIB, where the single-step process yields better purity.7.2 Induction Furnace-Assisted Self-Propagating High-Temperature Synthesis

[0087] An alternative method for synthesizing MAB phase catalysts is by heating the powder mixture (prepared as outlined above) in an induction furnace, which is used to initiate a self-propagating high-temperature synthesis (SHS) reaction. In this case, a single-step process is generally used, i.e. by mixing a metal powder (Cr, Mo, Fe, Mn or W) with aluminum and boron. The metal boride is rarely mixed with aluminium and exposed to the synthesis process described above for the two-step process. In this process, the starting powders are usually subjected to high-energy ball milling prior to heating in the induction furnace. Occasionally, the powders are only mixed by hand prior to synthesis. The powder mixtures are usually pressed into a pellet and rarely are they loaded into the furnace as loose powders. The induction furnace consists of a set of water-cooled copper induction coils. These coils inductively heat a graphite crucible which iscontained within a sealed silica tube. The sample is placed within the crucible and the tube is filled with a flowing inert atmosphere or placed under vacuum conditions to remove the air prior to the heating process starting. Samples produced in this way are usually, but not always, lower purity than those produced in a tube furnace. Synthesis via an induction furnace is faster and cheaper than material produced with the tube furnace. This process may be used to create the metal boride material prior to mixing with aluminium for the two-step process in the tube furnace.1.3 Hot-Press Furnace

[0088] Analogous to the tube furnace method, a hot-press tube furnace may also be used to create high-density pellets (up to about 98% of theoretical maximum density). The sample preparation methods and options for preparing and performing the synthesis are the same as for the tube furnace. The main difference is that the mixed powder is loaded into a graphite die which is compressed by a hydraulic press while the sample is heated. This allows for the material to effectively sinter together while the solid-state reaction occurs. For most MAB phases, the two-step process yields higher purity compounds than the single-step process. Once again, the opposite is true for WAIB, in which the single-step process yields higher purity.EXAMPLE 2. Ambient catalytic activity and screening of MAB phase catalysts

[0089] Analysis of the catalytic activity of MAB phase catalysts in ambient conditions (T = 20 °C, P = 1 bar) was conducted using a long path-length FTIR cell (5 m) with detection of ammonia down to 1 ppm. All reactions were performed under standard lab light (no UV or other lamps were used). The analytical setup took several forms, separated broadly into two schemes: 1) gas reaction, and 2) liquid reaction. For the gas reactions, tank-stored air, ambient air or nitrogen gas were flow-controlled (10 mL / min) and coupled directly to a quartz-tube packed-bed style reactor housing the catalyst powder. The reactor outlet led to a multi-pass flow cell (5 m path length) equipped with KBr windows, fitted to an FTIR spectrometer. For the liquid-gas reactions, liquid deionised water (Milli-Q®) was added directly to the catalysts, either by spraying the catalyst with water mist during the reaction, or by submerging the catalyst powders completely in liquid water. In those experiments, ambient air was drawn through the catalyst with the aid of a vacuum system, needle valves and / or mass flow controllers, using 10 mL / min as the standard flow rate, with the outlet product gas flowing to the FTIR spectrometer. For the gas reaction experiments, unless otherwise specified in the figure captions, 0.2 g of catalyst was used. For the liquid-gas experiments, unless otherwise specified in the figure captions, 2 g of catalyst was used.Table 1. Parameters for the synthesis of MAB phase catalystsTarget Compound Starting materials Synthesis Synthesis Time (h) Heating Current (A) Applied Pressure (typical molar ratio) Temperature (°C) (MPa) Tube Furnace SynthesisCr2AIB2CrB+AI (2: [1.5- 1.7]) 900-1000 1-20 N / A N / ACr3AlB4CrB+AI+B (3:[1.5-1.7]: 1) 900-1000 1-20 N / A N / ACr4AlB6CrB+AI+B (4:[1.5-1.7]:2) 900-1000 1-20 N / A N / AMoAIB MoB+AI (1:1.3) 1000-1300 1-20 N / A N / AMoAIB Mo+AI+B (1:1.3:1) 1000-1300 1-20 N / A N / AFe2AIB2FeB+AI (2:1.15) 1000-1250 1-20 N / A N / AFe2AIB2Fe+AI+B (2:1.15:2) 1000-1250 1-20 N / A N / AMn2AIB2MnB+AI (2:1.15) 1000-1200 1-20 N / A N / AMn2AIB2Mn+AI+B (2:1.15:2) 1000-1200 1-20 N / A N / AWAIB WB+AI (1:1.3) 650-750 1-20 N / A N / AWAIB W+AI+B (1:1.3:1) 650-750 1-20 N / A N / ACrB Cr+B (1:1) 1200-1300 2-3 N / A N / AMoB Mo+B (1:1) 1200-1300 2-3 N / A N / AFeB Fe+B (1:1) 1200-1300 2-3 N / A N / AMnB Mn+B (1:1) 1200-1300 2-3 N / A N / AWB W+B (1:1) 1200-1300 2-3 N / A N / AInduction-Assisted SHSCr2AIB2Cr+AI+B (2:[2-4]:2) NA 2-3 min 180-245 NAMoAIB Mo+AI+B (1:[1.4-1.6]: 1) N / A <2 min 145-200 N / AFe2AIB2Fe+AI+B (2:[1.2-1.4]:2) N / A <2 min 145-200 N / AMn2AIB2Mn+AI+B (2:[1.3-1.5]:2) N / A <2 min 145-200 N / ACrB Cr+B (1:1) N / A 2-3 min 180-245 N / AMoB Mo+B (1:1) N / A <2 min 145-200 N / AFeB Fe+B (1:1) N / A <2 min 145-200 N / AMnB Mn+B (1:1) N / A <2 min 145-200 N / AWB W+B (1:1) N / A <2 min 145-200 N / AHot-Press Furnace SynthesisCr2AIB2CrB+AI (2:[1.5-1.9]) 1000-1300 1-4 N / A 30-50Cr3AlB4CrB+AI+B (3:[1.5-1.9]: 1) 1000-1300 1-4 N / A 30-50Cr4AlB6CrB+AI+B (4:[1.5-1.9]:2) 1000-1300 1-4 N / A 30-50 MoAIB MoB+AI (1:[1.3-1.5]) 1200-1400 1-4 N / A 30-50 MoAIB Mo+AI+B (1:[1.3-1.5]: 1) 1200-1400 1-4 N / A 30-50 Fe2AIB2FeB+AI (2:[1.15-1.3]) 1200-1400 1-4 N / A 30-50 Fe2AIB2Fe+AI+B (2:[1.15-1.3]) 1200-1400 1-4 N / A 30-50 WAIB WB+AI (1:1.3) 650-750 1-20 N / A 30-50WAIB W+AI+B (1:1.3:1) 650-750 1-20 N / A 30-50

[0090] Typical schematics of the setup are provided in Figures 2 a-b. For the standard flow rate used across the majority of experiments (10 mL / min), the time required to fill the cell was -135 min. Once the cell was full, a number of spectra (e.g. 8, 512, 1024) were collected and averaged to obtain the final spectrum, which was analysed for quantification of the yield of NH3. Quantification of the resulting FTIR spectra was performed using Beer’s law by comparing the measured data to that of a 100 ppm library reference scan for ammonia within QAsoft (GramsAI). Reaction rates were calculated by combining the NH3 ppm measured for each experiment with the time taken to fill the multi-pass cell and the mass (g) of catalyst used.

[0091] The catalysts were prepared according to the tube furnace method described above at 1.1. Cr2AIB2, MoAIB and Fe2AIB2were prepared according to the two-step tube furnace method by synthesising the corresponding binary transition metal boride precursor powders first and then mixing with the appropriate ratio of aluminium prior to the final reaction. Mn2AIB2 was prepared following the single-step tube furnace process. XRD analysis was performed on the MAB phase samples to confirm phase purity prior to use for the NH3 production experiments.

[0092] A preliminary screening of the catalysts, Cr2AIB2, Mn2AIB2, MoAIB, and Fe2AIB2, found that Cr2AIB2 possesses greater catalytic activity under ambient conditions (6 ppm) than the other MAB phase catalysts tested (-1 ppm; Figure 3). Consequently, Cr2AIB2 was chosen for further testing. For these experiments, 200 mg catalyst was used with 10 mL / min air flow rate.

[0093] Next, the effects of air vs nitrogen as a feedstock were investigated. Both were found to produce ammonia, although the exact impact is somewhat inconclusive. For both feedstocks, around 6 ppm ammonia was produced (Figure 4).

[0094] The effect of water was investigated, first by bubbling the air feedstock through a saturator filled with water to develop water vapor in the feedstock gas. A small improvement was noticed in this case, but results were somewhat inconclusive (Figure 5). Next, the catalyst was completely submerged in water. This resulted in a two-fold increase in the ammonia concentration to 12 ppm (Figure 6).

[0095] A preliminary investigation of the impact of air flow rate on the yield of ammonia was conducted. Faster flow rates correlated with lower concentrations. However, faster flow rates also correlated with higher overall yields. A total of 11 experiments were performed (3 of which shown in Figure 7) ranging from 3 min - 35 min and achieving ammonia concentrations of 3 - 7 ppm. The time represents the time taken to completely fill the evacuated FTIR cell (1.33 L) with product gas. From these tests, an average of 13.91 mg / h / gcataiyst and a maximum of 55.86 mg / h / gcatalystwere determined. It is noted that these results are for a non-optimized system. Improvements to the yield are expected for an optimized system using a similar setup.

[0096] Understandably, concentration of ammonia gas in the case where the catalyst is suspended in water is separate to any ammonia produced within the water and trapped in solution as ammonium (NH4+). In this case, the pH of the water was measured as a function of time to map ammonia production. A quick increase in the pH of the distilled water was observed after 1 day, after which the pH slowly increased, resulting in a concentration of ~1.1mmol / L (NH4+) after compensating for equilibrium atmospheric CO2 causing acidification (Figure 8).EXAMPLE 3. Design and development of a thermal ammonia reactor

[0097] A benchtop thermal ammonia reactor was designed and commissioned to provide data regarding the invention, namely providing proof that the catalyst(s) may produce ammonia directly from air or nitrogen and water (including steam) in a thermal-style reactor.3.1 Methods

[0098] The schematic in Figure 9 outlines the process for introducing water or steam and air or nitrogen to the catalyst in a thermal-style reactor configuration as a means to assess the impact of process variables, mainly temperature, pressure and water phase, on the ammonia production rates. All gas lines and fittings were constructed from 316 stainless steel.

[0099] Pressurised gas, air or N2 was fed into the system, manually controlled by a needle valve and mass flow meter until the desired flow rate was achieved. Nitrogen was sourced in the form of a commercial (Grade 4.0) compressed gas cylinder and air was sourced either from ambient air using a dedicated air compressor, or using an Industrial Grade compressed gas cylinder. For these experiments, a gas flow rate of ~ 0.7 g / m was used. Demineralised water was pressurised using a bladder accumulator, passed through a mass flow controller and mixed with the gas to achieve a mass ratio of gas:water = 0.25: 1. This feedstock mixture was passed through a temperature-controlled boiler / superheaterto achieve the desired feedstock mixture temperature and was then introduced to the vertically-oriented NH3 reactor packed with 32 g of Cr2AIB2 catalyst. A stainless steel sheet with 50 pm pores was loaded into the reactor underneath the catalyst bed to support the catalyst and prevent loss of the powder through the outlet. The reactor was temperature-controlled using heater bands. The product stream exiting the reactor passed through a condenser, cooling the stream to below ambient temperatures (~5 °C). The liquid output, NH₃(aq) was collected and the NH3 content measured using a standard Nessler Reagent based colourimeter process. The gas stream was passed through a sensor bank measuring various possible byproducts including O2, H2, NOX, N2O, NO2, O3 and gaseous NH3.3.2 Results[000100] A summary of the results from the thermal reactor testing are shown in Figure 10 and reported as mg of NH3 per g of catalyst per h. As expected, increased temperature and pressure yield higher single pass yields. Additionally, it was found that using air rather than pure nitrogen resulted in improved yields.[000101] Figure 11 shows that the catalyst is definitely active for ammonia production since replacing it with an inert material (SiC) under the same conditions yielded no ammonia. Similarly, using argon rather than nitrogen as a control feed gas sample revealed that some ammonia is produced in the absence of nitrogen feedstock. This matches expectations, since the catalyst has been observed to reduce ambient nitrogen upon removal from the furnace post-synthesis. This reflects the belief that there may be reduced nitrogen species bound to the catalyst surface prior to entering the reactor, and those surface-bound nitrogen species can be further converted to ammonia in an argon + water feedstock mixture, even with the absence of dedicated nitrogen delivery to the reactor.[000102] Oxygen gas composition in the outlet gas stream was found to increase (above the feedstock composition) as ammonia formation increased. No additional hydrogen was detected. Together, these findings indicate that separation of hydrogen from the feedstock water occurred, with that hydrogen being completely consumed in the formation of ammonia and the excess oxygen remaining from the separation process recombining into oxygen gas and continuing through the reactor.EXAMPLE 4.15Nz Isotope testing[000103] To validate that the ammonia being measured in the aqueous and gaseous products originated from the feedstock and not from environmental contamination or from the catalyst itself, isotopically labelled nitrogen (15N2) was employed as the feedstock. A positive result is categorised by measurement of15NH₃ rather than typical14NH₃ produced using standard air or nitrogen gas sources. Equipment capable of differentiating15NH₃ from14NH₃ in both liquid and gas forms is needed to perform this task, namely NMR (nuclear magnetic resonance) spectroscopy and GC-MS (gas chromatography-mass spectroscopy), with the GC functioning to separate the gas species with overlapping M / Z (mass to charge) ratios measured by MS.4.1 Methods[000104] The thermal reactor for isotope testing was set up as shown in Figure 12. Due to the scarcity and cost of15N2, as well as to prevent unwarranted environmental contamination and inline dead volumes, a simplified miniaturised reactor was constructed to allow reduced gas consumption. Again, 316 stainless steel tube and fittings were employed with the exception of short plastic tube and fittings only at the inlets, to allow integration of the gas and water feeds.For each experiment, 0.8 g of Cr2AIB2 catalyst was loaded into the reactor in a packed-bed configuration, supported by a wad of nickel foam at the outlet. Experiments were all performed with the reactor pre-heated and controlled to 90°C, at ambient pressure.[000105] Prior to testing, the demineralised water was purged by bubbling argon gas through it for 2 h to remove dissolved nitrogen. Two volumetric plungers were used to feed the gas and water feedstock into the reactor. A 50:50 N2 / O2 gas mix (by volume) was selected for these tests, to prove catalytic reduction of N2 in the presence of O2. For the mixture, Grade 5.0 O2 and either Grade 4.014N2 or15N2 (Sigma Aldrich: >99.9% purity, >99.8% isotopic enrichment) was used. The gas mix was fed into the reactor along with the water, at a rate of 30 mL / min of gas and 0.1 mL / min of water, for a total of 900 mL gas and 3 mL water. The aqueous product was tested by Nessler Reagent to measure the ammonia concentration, and the gas outlet was collected in a freshly purged and vacuumed gas bag connected to the reservoir outlet.[000106] Testing was conducted with both 15N2 and 14N2 for comparison under the same experimental conditions.[000107] Aqueous ammonia samples were prepared for NMR spectroscopy (600 MHz, Bruker) by being slightly acidified with 0.1M HCI to adjust pH, forcing dissolved NH3 into NH4+(ammonium) in the solution. D2O + 1% DSS was used as a lock and internal standard for the NMR. A 1H scan was performed with mild water suppression to separate the NH4+peaks (~7.0 - 7.2 ppm chemical shift range) from the tail of the significant water peak.[000108] Product gas samples were extracted directly from the gas bags into syringes which were then passed through a GC-MS system.4.2 Results[000109] The NMR data in Figure 13 clearly indicates that no15NH4+was produced when the14N2 feedstock was used, as expected. When the15N2 feedstock was used, both14NH4+and15NH4+were produced, at a ratio of 37%15NH4+, 63%14NH4+. Similar to the argon control experiment in Figure 9, this matches expectations, since the catalyst is known to reduce ambient nitrogen upon removal from the furnace post-synthesis. The presence of14NH4+likely reflects this fact, with reduced ambient nitrogen species stuck to the catalyst surface prior to entering the miniature reactor, and converting those reduced nitrogen species into14NH4+alongside the fresh15N2 feedstock which was converted to15NH4+.[000110] These findings were further reinforced with the GC-MS analysis of the product gas species. In this case, Figure 14 (top plot) shows the presence of a15NH₃ peak at M / Z = 18 when the15N2 isotope gas feedstock was used, clearly separate from the H2O peak at M / Z = 18 due topre-separation by the GC. In contrast, when standard14N2 gas feedstock was used (bottom plot), no15NH₃ peak could be identified, with only the H2O peak appearing for M / Z = 18.[000111] Collectively, the NMR spectroscopy and GC-MS analysis confirms that the catalyst, operating in a thermal reactor, converts fresh feedstock nitrogen directly into ammonia, even in the presence of oxygen gas. This finding alone is considered unique as metal-based catalysts generally bind with oxygen and succumb to oxidation, preferentially to binding with (and activating / reducing) nitrogen, and further still converting the reduced nitrogen feedstock to ammonia in the presence of water.EMBODIMENTS OF THE INVENTION[000112] Other embodiments of the invention as described herein are defined in the following paragraphs:1. A process for the production of ammonia comprising contacting a hydrogen feedstock with a MAB phase catalyst in the presence of nitrogen in a thermal chemical reactor.2. The process according to paragraph 1, wherein the hydrogen feedstock comprises water.3. The process according to paragraph 1 or 2, wherein the hydrogen feedstock comprises steam or water vapor.4. The process according to paragraph 1, wherein the hydrogen feedstock comprises hydrogen gas.5. The process according to any one of paragraphs 1 to 5, wherein the nitrogen is present in the form of air.6. The process according to paragraph 5, wherein the hydrogen feedstock is mixed with air prior to contacting the MAB phase catalyst.7. The process according to any one of paragraphs 1 to 4, wherein the hydrogen feedstock is mixed with nitrogen gas prior to contacting the MAB phase catalyst.8. The process according to paragraph 6 or 7, wherein the hydrogen feedstock is further mixed with a material selected from the group consisting of natural gas, coal, petroleum, peat, or biomass.9. The process according to any one of paragraphs 1 to 8, wherein the MAB phase catalyst is selected from the group consisting of MoAIB, WAIB, Fe2AlB2, Mn2AlB2, Cr2AlB2, Cr3AlB4, Cr4AlB6, Cr4AlB6, and combinations thereof.10. The process according to paragraph 9, wherein the MAB phase catalyst is Cr2AlB2.11. The process according to any eno of paragraphs 1 to 10, wherein the hydrogen feedstock and nitrogen are contacted with the MAB phase catalyst at a temperature of between about 30 °C and about 650 °C.12. The process according to paragraph 11, wherein the hydrogen feedstock and nitrogen are contacted with the MAB phase catalyst at a temperature of between about 450 °C and about 550 °C.13. The process according to paragraph 11 or 12, wherein the hydrogen feedstock and nitrogen are contacted with the MAB phase catalyst at a temperature of about 500 °C.14. The process according to any one of paragraphs 1 to 13, wherein the hydrogen feedstock and nitrogen are contacted with the MAB phase catalyst under increased pressure of between about 0.25 MPa to about 25 MPa.15. The process according to any one of paragraphs 1 to 14, wherein ammonia is collected by condensing gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.16. The process according to paragraph 15, wherein the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor are condensed at a temperature of between about -15 °C to about -25 °C.17. The process according to paragraph 15 or 16, wherein the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor are condensed under increased pressure of about 0.1 MPa to about 2 MPa.18. The process according to any one of paragraphs 15 to 17, wherein the ammonia is collected as an aqueous ammonia solution.19. The process according to any one of paragraphs 1 to 18, wherein the ammonia is collected by separating gaseous ammonia from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.20. The process according to any one of paragraphs 15 to 19, further comprising collecting or recirculating hydrogen from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.21. A process for the production of ammonia comprising contacting water with a MAB phase catalyst in the presence of nitrogen in a thermal chemical reactor.22. Ammonia produced by the process of any one of paragraphs 1 to 21.[000113] Although the invention has been described with reference to specific examples, it will be appreciated by those skilled in the art that the invention may be embodied in many other forms, and in particular features of any one of the various described examples may be provided in any combination in any of the other described examples. Various modifications and alterations to this invention will become apparent to those skilled in the art without departing from the scope and spirit of this invention. It should be understood that this invention is not intended to be unduly limited by the illustrative embodiments and examples set forth herein and that such examples and embodiments are presented by way of example only with the scope of the invention intended to be limited only by the claims set forth herein as follows.

Claims

CLAIMS1. A process for the production of ammonia comprising contacting a hydrogen feedstock with a MAB phase catalyst in the presence of nitrogen in a thermal chemical reactor.

2. The process according to claim 1, wherein the hydrogen feedstock comprises water.

3. The process according to claim 1 or 2, wherein the hydrogen feedstock comprises steam or water vapor.

4. The process according to claim 1, wherein the hydrogen feedstock comprises hydrogen gas.

5. The process according to any one of claims 1 to 4, wherein the nitrogen is present in the form of air.

6. The process according to claim 5, wherein the hydrogen feedstock is mixed with air prior to contacting the MAB phase catalyst.

7. The process according to any one of claims 1 to 4, wherein the hydrogen feedstock is mixed with nitrogen gas prior to contacting the MAB phase catalyst.

8. The process according to claim 6 or 7, wherein the hydrogen feedstock is further mixed with a material selected from the group consisting of natural gas, coal, petroleum, peat, or biomass.

9. The process according to any one of claims 1 to 8, wherein the MAB phase catalyst is selected from the group consisting of MoAIB, WAIB, Fe2AlB2, Mn2AlB2, Cr2AlB2, Cr3AlB4, Cr4AlB6Cr4AlB6, and combinations thereof.

10. The process according to claim 9, wherein the MAB phase catalyst is Cr2AlB2.

11. The process according to any one of claims 1 to 10, wherein the hydrogen feedstock and nitrogen are contacted with the MAB phase catalyst at a temperature of between about 30 °C and about 650 °C.

12. The process according to claim 11, wherein the hydrogen feedstock and nitrogen are contacted with the MAB phase catalyst at a temperature of between about 450 °C and about 550 °C.

13. The process according to claim 11 or 12, wherein the hydrogen feedstock and nitrogen are contacted with the MAB phase catalyst at a temperature of about 500 °C.

14. The process according to any one of claims 1 to 13, wherein the hydrogen feedstock and nitrogen are contacted with the MAB phase catalyst under increased pressure of between about 0.25 MPa to about 25 MPa.

15. The process according to any one of claims 1 to 14, wherein ammonia is collected by condensing gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.

16. The process according to claim 15, wherein the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor are condensed at a temperature of between about -15 °C to about -25 °C.

17. The process according to claim 15 or 16, wherein the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor are condensed under increased pressure of about 0.1 MPa to about 2 MPa.

18. The process according to any one of claims 15 to 17, wherein the ammonia is collected as an aqueous ammonia solution.

19. The process according to any one of claims 1 to 18, wherein the ammonia is collected by separating gaseous ammonia from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.

20. The process according to any one of claims 15 to 19, further comprising collecting or recirculating hydrogen from the gases produced by contacting the hydrogen feedstock and nitrogen with the MAB phase catalyst in the thermal chemical reactor.

21. A process for the production of ammonia comprising contacting water with a MAB phase catalyst in the presence of nitrogen in a thermal chemical reactor.

22. Ammonia produced by the process of any one of claims 1 to 21.

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