Catalyst materials for the thermal decomposition of methane and the production of hydrogen and solid carbon, with virtually zero carbon emissions into the atmosphere.

Abstract

A catalyst for the thermal cracking of hydrocarbons, such as methane or natural gas, includes a waste pile configured to promote the cracking of the hydrocarbons into hydrogen and carbon. The waste is one of bauxite residue, mill scale, or slag. The waste pile can be cracked into a powder or fragmented form.

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims the benefit of and priority to U.S. Non - Provisional Application No. 17 / 502,628, filed Oct. 15, 2021, which claims the benefit of and priority to U.S. Provisional Patent Application No. 63 / 093,399, filed Oct. 19, 2020, the entire contents of each of which are incorporated herein by reference.

[0002] This disclosure relates to the production of hydrogen and solid carbon materials by the pyrolysis of hydrocarbons. Specifically, this disclosure relates to catalysts for the pyrolysis of methane or natural gas, and the catalysts include waste - products.

Background Art

[0003] The decarbonization of the energy sector is of utmost importance for environmental issues related to global warming and climate change. Hydrogen, especially pure H2, is a well - known carbon - free energy carrier that is considered by many to be a promising alternative to fossil fuels, especially for use in power generation and transportation. The emergence of fuel cell technology has driven this alternative because fuel cells operate on hydrogen with high electrical efficiency and other environmental advantages.

[0004] However, hydrogen is not found on Earth in its free molecular state. Therefore, it must be extracted from hydrogen-containing compounds. The most mature technology involves extracting hydrogen from water by electrolysis (water splitting). This process is energy-intensive because the HO bonds in water are very stable and require a large amount of energy to break. More than 4 kWh of electricity is needed to produce one cubic meter of hydrogen by water electrolysis. Exacerbating the problem are the power sources consumed to produce pure H2 and the environmental impact of its production. In many parts of the world, the environmental footprint of this technology is questionable, as power generation involves the emission of enormous amounts of carbon and other air pollutants.

[0005] An alternative approach is to extract hydrogen from hydrocarbons such as methane (CH4), which is the main component (over 90-95%) of natural gas. This is a viable and technologically mature process, but it does emit carbon dioxide (CO2) from the carbon contained in the hydrocarbons. The amount of CO2 emitted may be small, but it is not zero. However, because the global supply of natural gas is very large and its carbon emissions are low, it is a technology that can be used as a transitional step between full-carbon and zero-carbon approaches.

[0006] Another alternative process for producing "blue hydrogen," i.e., hydrogen with virtually no carbon emissions, is the decomposition or thermal decomposition of methane or natural gas into gaseous hydrogen and solid carbon. Such processes produce the desired pure hydrogen, which can be used directly in fuel cells for power generation with no or limited CO2 emissions, as described in U.S. Patent No. 6,670,058 to Muradov. The solid carbon byproducts can be used in industrial processes or can be easily disposed of underground. When biogas (or biomethane) is used instead of natural gas, this process is a "negative" carbon emission because the carbon in biomethane is carbon absorbed from the atmosphere. The energy "penalty" of this process is defined as the energy loss from methane decomposition to produce hydrogen and the use of hydrogen in fuel cells for power generation, but is 15% less compared to power generation with natural gas in a turbine. If the produced carbon is utilized in industrial processes, the penalty is less, or even "negative."

[0007] The thermal decomposition of methane generally requires very high temperatures, typically exceeding 1200°C. Using a suitable catalyst, the required activation temperature of methane for thermal decomposition can be reduced. In the presence of a suitable catalyst, methane decomposition can occur at 800–900°C. The most promising catalysts contain nickel (Ni), iron (Fe), and cobalt (Co) and are supported on metal oxide materials such as aluminum oxide (Al₂O₃) and magnesium oxide (MgO). However, because catalysts accumulate carbon on their surface and become inactive after short-term use, methane decomposition on such catalysts is impractical and not economically feasible. Removing the accumulated carbon and reusing the catalyst is complex and expensive. Therefore, the catalyst and the solid material containing the accumulated carbon are often disposed of together. The high cost of the catalyst hinders the economic feasibility of the process. Therefore, a practical, economically feasible, and effective catalyst is desired for reducing the temperature requirements for methane thermal decomposition. [Overview of the Initiative]

[0008] This disclosure relates to a catalyst for the thermal decomposition of methane, comprising a pile of waste materials. The waste materials are configured to facilitate the decomposition of hydrocarbons into hydrogen and carbon. The waste materials are one of the following: refined bauxite residue, mill scale, or slag.

[0009] In one embodiment, the catalyst may include a substructure layered on the waste.

[0010] In this embodiment, the foundation structure may be fabricated, at least in part, from waste.

[0011] In other embodiments, the waste can be enhanced with nickel, cobalt, or iron additives.

[0012] In a further embodiment, the base structure may be made at least in part from nickel, cobalt, iron, aluminum oxide, or magnesium oxide.

[0013] In one aspect, the waste aggregate is broken down into powder or fragment form.

[0014] In one embodiment, the waste may be slag containing at least one of steel slag, copper slag, or nickel slag.

[0015] Another aspect of the present disclosure provides a method for producing hydrogen. The method includes passing a hydrocarbon over a waste catalyst, heating the hydrocarbon and the waste catalyst, thermally catalytically decomposing the hydrocarbon into hydrogen and solid carbon, and recovering the hydrogen in a container.

[0016] In one embodiment, the passage of hydrocarbons over the waste catalyst may include the passage of natural gas or methane over the waste catalyst.

[0017] In a further embodiment, the method may further include recovering solid carbon deposited on a waste catalyst.

[0018] In other embodiments, passing hydrocarbons over a waste catalyst can include passing hydrocarbons over a catalyst deposit of waste.

[0019] In the disclosed embodiments, passing hydrocarbons over a waste catalyst can include passing hydrocarbons over a waste catalyst that can include at least one of bauxite residue, slag, or mill scale.

[0020] In yet another alternative, passing hydrocarbons over a waste catalyst includes passing hydrocarbons over a waste catalyst that can include a substrate structure. The layer of waste material can be an outer layer on the substrate structure.

[0021] In a further embodiment, the waste catalyst can be included within a reactor.

[0022] In a further embodiment, the reactor is a fixed bed, fluid bed, moving bed, trickle bed, rotary bed, or slurry reactor.

[0023] In the disclosed embodiments, the method can include processing the waste catalyst into a powder or fragment form.

[0024] In an embodiment, the method can include heating the hydrocarbons and the waste catalyst from about 750 °C to about 950 °C.

[0025] In an embodiment, the method can include heating the hydrocarbons and the waste catalyst from about 500 °C to about 1300 °C.

[0026] These and other features and advantages of the present disclosure will become apparent from the following description and the accompanying drawings.

[0027] A better understanding of the features and advantages of the present disclosure can be obtained by reference to the following detailed description of the illustrative embodiments and the accompanying drawings.

Brief Description of the Drawings

[0028] [Figure 1]It is an image of an aggregate of a bauxite residue catalyst material.

[0029] [Figure 2] It is an image of an aggregate of a mill scale catalyst material.

[0030] [Figure 3] It is a diagram of an exemplary hydrogen generation rate when bauxite residue is used as a catalyst material.

[0031] [Figure 4] It is a diagram of an exemplary hydrogen generation rate when mill scale is used as a catalyst material.

[0032] [Figure 5] It is a diagram of a method for generating hydrogen according to another aspect of the present disclosure.

[0033] [Figure 6] It is a cross-sectional view of a waste catalyst in the shape of a flat bar.

MODE FOR CARRYING OUT THE INVENTION

[0034] Although the present disclosure is described from the perspective of specific embodiments, it will be readily apparent to those skilled in the art that various modifications, rearrangements, and substitutions can be made without departing from the gist of the present disclosure.

[0035] The description in this specification presents a number of specific details included to provide a thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that the present disclosure can be implemented without using some or all of these specific details. On the other hand, well-known process steps, procedures, and structures are not described in detail so as not to unnecessarily obscure the present disclosure.

[0036] The production of pure hydrogen and solid carbon materials by the thermal or thermally catalytic decomposition of methane is essential for the development of the hydrogen economy. Improving the sources and properties of catalysts used in the reaction is a crucial aspect of improving the feasibility of hydrogen production from natural gas or methane, the main component of natural gas. Improvements in catalyst properties are generally made in terms of reaction rate, minimization of operating temperature, and the ability to maintain thermochemical stability during the deposition of large nanocarbons. Therefore, various metal and carbon-based catalysts have been introduced. Metal-based catalysts are superior to carbon catalysts in terms of hydrogen production rate and reaction rate.

[0037] Transition metal catalysts, particularly Ni, Fe, and Co-based catalysts, are often used to improve catalytic reactions during pyrolysis. Ni-based catalysts are distinguished from metallic catalysts by their relatively low cost, low toxicity, superior activity, stability, and environmentally friendly properties. Metallic catalysts have a longer catalyst lifetime by maintaining a nanocarbon formation mechanism that retains the active metal sites at the top of the catalyst toward the reaction medium. The growth mechanism of nanocarbon or solid carbon products from pyrolysis involves the diffusion of deposited carbon through the active metal sites. The diffused nanocarbon then precipitates on the opposite side of the metal particles, forming longer carbon filaments.

[0038] The catalytic activity and stability of the catalyst used in this method, as well as the properties of the as-produced nanocarbon, are both crucial in thermocatalytic decomposition (TCD) because they play a vital role in determining the overall yield and structure of the resulting solid carbon byproducts and hydrogen. Solid carbon accumulates on the catalyst until it saturates it, thereby inactivating it. Once inactivation is nearly complete, the catalyst, along with the solid carbon it contains, can be disposed of in a suitable manner or used in other processes.

[0039] Solid carbon byproducts from the pyrolysis or TCD of methane are generally in the form of nanocarbon, graphite carbon, or carbon nanotubes. This offers additional economic advantages over producing hydrogen by pyrolysis or TCD, and in some applications, environmental advantages (by reducing the need to dispose of otherwise useless solid carbon). For example, graphite carbon byproducts can be used in a variety of industrial and consumer applications, such as pencil tips, high-temperature crucibles, dry cell batteries, and electrode manufacturing, or as lubricants, among many other applications known to those skilled in the art. Carbon nanotubes (CNTs) are cylinders consisting of one or more layers of graphene (lattice), known as single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs), with diameters of 0.8–2 nm in the case of SWCNTs and 5–20 nm in the case of MWCNTs. CNTs are structural materials with desirable properties and are used in applications including, but not limited to, energy storage, device modeling, automotive parts, boat hulls, sporting goods, water purifiers, thin-film electronics, coatings, actuators, and electromagnetic shielding.

[0040] Providing low-cost, environmentally friendly, and abundant catalyst materials reduces the need to improve the properties of expensive catalyst materials or to develop methods for reusing catalysts.

[0041] This disclosure describes a family of waste materials that form “waste” catalysts or catalytic materials, which can facilitate the thermal catalytic decomposition (pyrolysis) of methane or natural gas into hydrogen and solid carbon, and can be used for the production of pure hydrogen with low carbon, near carbon, or “negative” carbon. Since the catalyst is composed of waste materials that would otherwise have to be disposed of, it is carbon neutral, enables carbon consumption, and is environmentally friendly. Waste catalysts are produced from waste materials and enable the thermal decomposition or thermal catalytic decomposition (TCD) of methane at lower temperatures than would be possible without a catalyst. Additionally, due to the abundance of these waste materials, it is economical and feasible to replace used “waste” catalysts, as these materials would normally be disposed of, for example, in landfills. This thus mitigates the problem of solid carbon deposits that often accumulate on top of and deactivate more expensive catalyst materials. Waste catalysts may include slag, mill scale, bauxite residue, or similar waste containing sufficient levels of iron for TCD.

[0042] Waste catalysts are useful for decomposing methane or natural gas. When these materials are used as waste catalysts in methane TCD, the following reactions occur:

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[0043] Referring to Figure 1, waste catalysts are produced from bauxite residue (bauxite tailings), commonly referred to as "red mud." The red mud is dried and used as a catalyst in the form of "powder" or "piece-meal." Red mud is mainly composed of iron oxide. Bauxite residue is a byproduct of the process of extracting aluminum from bauxite ore, particularly by a method known to those skilled in the field of aluminum extraction as the Bayer process.

[0044] In the Bayer process, bauxite ore mined from open-cut mines is treated with sodium hydroxide, also known as caustic soda, at high temperatures to selectively dissolve aluminum from a range of other mineralized metals. The final products are alumina (Al2O3), used to produce aluminum metal, and bauxite residue. For every ton of alumina produced, approximately 1 to 1.5 tons of red sludge are generated. Generally, the generated red sludge is stored in ponds, has few other uses, and is not environmentally friendly. As of 2018, the annual production of alumina was approximately 126 million tons, resulting in the generation of 160 million tons of red sludge, so there is a need for appropriate and environmentally friendly use of red sludge.

[0045] By producing waste catalysts from red clay, not only is efficient and effective pyrolysis achieved, but waste from the Bayer process is reused, reducing the environmental impact of both the pyrolysis and Bayer processes. Furthermore, the abundant red clay makes it an attractive and economical material for catalysts.

[0046] The bauxite residue can be dried by various methods, such as kiln drying or sun drying, and then processed to form catalyst aggregates in the form of "powder" or "fragments" (small lumps and pieces). The dried red clay can be placed in and sealed in a chemical reactor for thermal decomposition. The reactor may be a fixed-bed, fluidized-bed, moving-bed, trickle-bed, rotating-bed, or slurry reactor. Any suitable reactor known to those skilled in the art of chemical or thermal decomposition can be used. By directly placing the dried red clay catalyst aggregate in a chemical reactor, in addition to saving carbon and producing hydrogen, the manufacturing cost of the catalyst material is reduced because further processing of the catalyst is not required.

[0047] In one embodiment, the waste catalyst may include a catalyst base structure coated with a layer of purified or dried red clay. In one embodiment, the base structure may be made from red clay, and dried red clay may then be laminated onto the catalyst base structure. The dried red clay may be configured to form the entire catalyst structure. In one embodiment, nickel (Ni), cobalt (Co), or iron (Fe) metal or compound may be added to the red clay to improve the catalytic performance of the red clay.

[0048] Bauxite residue may contain 30-60 wt% iron(III) oxide (Fe2O3), 10-20 wt% aluminum oxide (Al2O3), 3-50 wt% silicon dioxide (SiO2), 2-10 wt% sodium oxide (Na2O), 2-8 wt% calcium oxide (CaO), and approximately 0-25 wt% titanium dioxide (TiO2). Additionally, trace amounts of MgO are often found in the red mud. Al2O3, SiO2, MgO, and TiO2 are known in the art to improve catalytic performance, as discussed in the article "A review on methane transformation to hydrogen and nanocarbon: Relevance of catalyst characteristics and experimental parameters on yield" by Ashik et al. in the journal Renewable & Sustainable Energy Reviews March 2017. Specifically, SiO2 as a catalytic additive is an effective material for promoting catalytic reactions in thermal decomposition. Therefore, dried bauxite residue in aggregates of "powder" or "fragments" is a desirable catalyst material.

[0049] The red clay can be purified to contain the desired amounts of each of its components. The red clay can be layered on a base structure containing Co, Ni, Fe, or metal oxides such as Al2O3 or MgO. The catalyst base structure can be any shape, size, or geometric shape known to those skilled in the art. The catalyst base structure can be cylindrical, cubic, rod-shaped, honeycomb-shaped, or any other desired shape.

[0050] In another aspect of this disclosure, the waste catalyst comprises solid particles or flakes derived as waste material from the manufacture and processing of steel, and is composed of steel without any mixtures. In an aspect, the solid particles or flakes may be mill scale produced as a byproduct from the steel rolling process. Mill scale is a flaky surface or thin iron oxide layer of hot-rolled steel and consists of mixed iron oxides such as iron(II) oxide (FeO), iron(III) oxide (Fe2O3), and iron(II,III) oxide (Fe3O4, magnetite). In an aspect, the mill scale waste material may consist of about 40% to about 100% Fe2O3 or more than about 90% Fe2O3. The mill scale is collected to form a catalyst aggregate and placed in a suitable reactor such as a fixed bed, fluidized bed, moving bed, trickle bed, rotating bed, or slurry reactor. Any suitable reactor known to those skilled in the art of chemical or pyrolysis may be used.

[0051] In another embodiment of this disclosure, slag, a by-product of waste material remaining after a metal has been separated from its ore, may be used as all or part of a waste catalyst. The slag is collected to form a catalyst aggregate to form the waste catalyst. The slag may be broken down into “powder” or “fragment” forms, collected, and formed into a catalyst aggregate. The slag catalyst aggregate is placed in a suitable reactor as described above with respect to mill scale and red clay.

[0052] Slag generally consists of a mixture of metal oxides and silicon dioxide (SiO2), but may also contain metal sulfides, magnesium oxide (MgO), and other elemental metals. Typical compositions of various types of slag are shown in Table 1: [Table 1]

[0053] Slag may be, for example, steel slag produced during the refining of crude iron (also called pig iron) in the steel industry. Crude iron refining is often carried out in a basic oxygen furnace (BOF) or electric arc furnace (EAF) to oxidize various residual gangues that are separated by floating on the molten iron. Table 2 shows exemplary compositions by weight percentage (Wt%) of steel slag produced using BOF or EAF. [Table 2]

[0054] In this embodiment, the slag may be nickel slag (Ni slag). Ni slag is produced as waste material in the production of nickel metal. Nickel matte is produced by smelting nickel ore, which may be pentland ore mixed with Fe and S as (Ni,Fe)9S8. Nickel matte contains nickel and iron sulfide. The nickel matte can then be treated in an electric furnace in which the iron in the nickel matte is oxidized, and the iron can be combined with silica to produce slag containing about 30% or less to about 40% by weight or more of FeO. A converter furnace can further purify the nickel matte from the iron oxide remaining in the nickel matte to produce slag containing about 60% or less to about 66% or more of FeO. Table 3 shows an exemplary composition of Ni slag. [Table 3]

[0055] In another embodiment, the slag may be copper slag (Cu slag) produced as waste material in the smelting process of copper ore, which exists as iron sulfate copper (e.g., CuFeS2 or Cu5FeS4) to produce copper matte. The copper matte is then treated to remove iron, sulfur, and gangue material from it. Silica may be added to the smelt because it interacts with the iron oxide in the copper matte to form a floating layer that can be separated from the smelt. The iron oxide mixed with silica forms the copper slag. Table 4 shows exemplary compositions of Cu slag. [Table 4]

[0056] In one embodiment, the slag or mill scale may be layered on the catalyst base structure or may form the entire catalyst base structure. In one embodiment, the catalyst base structure may include multiple layers of slag and / or mill scale.

[0057] In another aspect of this disclosure, raw iron ore, though not waste, is broken down into “powder” or “fragment” forms and collected for use in thermal decomposition within a chemical reactor to form catalyst aggregates. Iron ore is generally mined for the extraction of its iron used to make steel and is typically not waste, but rather a raw material processed into future products. In its unprocessed state, iron ore is an inexpensive material compared to many standard catalysts. Slag and mill scale are residues or waste after iron ore has been processed.

[0058] Slag, mill scale, and red sludge are materials that already require disposal and possess desirable properties for pyrolysis, thus providing attractive materials for creating waste catalysts for pyrolysis. Table 5 below provides a comparison of the carbon accumulation ratios of red sludge and mill scale compared to typical catalyst materials. A higher ratio means that more carbon separates from hydrocarbons (e.g., methane) and accumulates on the catalyst; therefore, a higher ratio of grams of carbon per gram of catalyst produces more hydrogen. The amount of carbon accumulated on the waste catalysts (red sludge and mill scale) is comparable to conventionally used catalysts. Notably, the carbon accumulation ratio of mill scale surpasses that of many other catalysts. [Table 5]

[0059] Referring to Figure 3, a graph shows the hydrogen production rate when a dried red clay catalyst aggregate was used for the thermal catalytic decomposition (pyrolysis) of methane over time in an exemplary experiment. Nearly pure methane was decomposed at 900°C. The dried red clay used in the exemplary experiment weighed 300 milligrams (mg) and contained approximately 100 mg of Fe. After 220 minutes, approximately 500 mg of carbon had accumulated on the red clay. After 220 minutes, approximately 1,850 cubic centimeters (cc) of hydrogen (H2) were produced, which corresponds to approximately 0.55 kilograms (kg) of H2 per kilogram of red clay. In the exemplary experiment, the hydrogen production rate by pyrolysis using the red clay catalyst aggregate ranged from approximately 15 cc (cc / min) to approximately 5 cc / min.

[0060] Referring to Figure 4, a graph of the hydrogen production rate when a mill scale catalyst aggregate was used for thermal decomposition over time in an exemplary experiment is shown. Nearly pure methane was decomposed at 900°C. The amount of mill scale catalyst aggregate used in this example was 300 mg. After 2,000 minutes, approximately 2,850 mg of carbon had accumulated on the iron slag catalyst aggregate. Approximately 10,600 cc of H2 was produced, which corresponds to approximately 3.15 kg of H2 per 1 kg of iron slag catalyst aggregate. In the first 120 minutes, the hydrogen production rate by thermal decomposition using the mill scale catalyst aggregate increased to a peak of approximately 25 cc / min, and then decreased to approximately 3 cc / min after 2,000 minutes.

[0061] In another aspect of the Disclosure, a method 500 for producing hydrogen from a hydrocarbon such as methane or natural gas includes a step 510 of passing the hydrocarbon over a waste catalyst of the Disclosure. In step 520, the method includes heating the hydrocarbon to a desired temperature in the presence of the waste catalyst of the Disclosure. In an embodiment, the hydrocarbon may be heated from 500°C to about 1300°C. In an embodiment, the hydrocarbon and the waste catalyst are heated from about 750°C to about 950°C. In another step 530, the hydrocarbon (e.g., methane) is decomposed into pure hydrogen and solid carbon. This method includes generating solid carbon on the surface of the waste catalyst. In an embodiment, only solid carbon and not gaseous carbon are produced as a byproduct. In another step 540, the method includes recovering the hydrogen into a container. This method may include heating the catalyst using the generated hydrogen. In another step 550, the method includes recovering the solid carbon from the waste catalyst. In an embodiment, the waste catalyst is a catalyst aggregate comprising at least one of red mud, mill scale, or slag. In this embodiment, the solid carbon and waste catalyst are disposed of underground to prevent carbon from escaping into the atmosphere.

[0062] Referring to Figure 6, an exemplary waste catalyst 600 includes a base structure 610 and a waste outer layer 620. The base structure 610 may be made from any suitable material such as Ni, Co, or Fe, a metal oxide such as MgO or Al2O3, or a nonmetal such as ceramic. The waste layer 620 may contain one or more waste materials such as bauxite residue, slag, or mill scale. In some embodiments, the waste layer 620 may contain multiple sublayers of waste. Additives can be mixed with the waste to enhance the waste's ability to accelerate thermal decomposition and recover solid carbon deposits. Figure 6 shows a rod-shaped waste catalyst, but any suitable shape or structure may be used. In some embodiments, the base structure 610 is configured to hold the waste catalyst aggregate. In some embodiments, the waste layer 620 is a waste catalyst aggregate placed on the upper surface of the base structure 610.

[0063] Certain aspects of this disclosure may include, include all, or none of, some of the above-mentioned advantages and / or one or more other advantages that are readily apparent to those skilled in the art from the drawings, descriptions and claims contained herein. Furthermore, while certain advantages are listed above, various aspects of this disclosure may include all, some, or none of the listed advantages and / or other advantages not specifically listed above.

[0064] The phrases “in one aspect,” “in one aspect,” “in various aspects,” “in several aspects,” or “in other aspects” may each refer to one or more identical or different aspects of the present disclosure. The phrase “A or B” means “(A), (B), or (A and B).” The phrase “at least one of A, B, or C” means “(A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C).”

[0065] It should be understood that the above description is merely illustrative of the present disclosure. Various substitutes and modifications can be devised by those skilled in the art without departing from the present disclosure. Accordingly, the present disclosure is intended to encompass all such substitutes, modifications, and variations. The embodiments described with reference to the accompanying drawings are presented solely to illustrate certain examples of the present disclosure. Other elements, steps, methods, and techniques substantially different from those described above and / or in the accompanying claims are also intended to be within the scope of the present disclosure.

Claims

1. A catalyst for the thermal decomposition of hydrocarbons, comprising a waste aggregate configured to promote the decomposition of the hydrocarbons into hydrogen and graphite solid carbon, wherein the waste aggregate is configured to recover the graphite solid carbon thereon. The catalyst further includes a base structure laminated on the waste, The aforementioned foundation structure is made at least in part from the aforementioned waste, The aforementioned waste is Mill scale containing approximately 40% to 100% by weight of Fe₂O₃, or Slag containing at least one of the following: steel slag containing approximately 22% to 60% by weight of CaO, nickel slag containing approximately 30% to 66% by weight of FeO, or copper slag containing approximately 55% to 70% by weight of Fe₂O₃. One of them is a catalyst.

2. The catalyst according to claim 1, wherein the waste is enhanced with nickel, cobalt, or iron additives.

3. The catalyst according to claim 2, wherein the basic structure is made at least in part from nickel, cobalt, iron, aluminum oxide, or magnesium oxide.

4. The catalyst according to claim 1, wherein the waste aggregate is decomposed into powder or fragment form.

5. The catalyst according to claim 1, wherein the solid carbon is at least one of graphite or graphene.

6. The catalyst according to claim 1, wherein the waste is steel slag further containing about 10% to about 35% by weight of FeO.

7. The catalyst according to claim 1, wherein the waste is nickel slag further comprising about 5% to about 8% by weight of SiO₂, or about 32% to about 42% by weight of SiO₂.

8. The catalyst according to claim 1, wherein the waste is copper slag further containing about 25% to about 35% by weight of SiO₂.

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