Process and apparatus for the production of hydrocarbons

Abstract

The present invention relates to a method and a preparation apparatus for preparing hydrocarbons from organic waste. The method and the preparation apparatus for preparing hydrocarbons according to the present invention can significantly increase the yield of preparing hydrocarbons from organic waste, and can expand the product group obtainable from organic waste. Furthermore, the generation of carbon dioxide in the process of preparing hydrocarbons can be minimized.

Description

Technical Field

[0001] This invention relates to a method and apparatus for preparing hydrocarbons from carbon dioxide. Background Technology

[0002] The concentration of carbon dioxide in the atmosphere has increased dramatically due to increased carbon dioxide (CO2) emissions from the excessive burning of fossil fuels. South Korea's industrial sector has seen a year-on-year increase in CO2 emissions, reaching nearly 350 million tons in 2020. This increase in CO2 emissions is a major cause of abnormal climate phenomena, including global warming.

[0003] Against the backdrop of a greater-than-ever societal demand for reducing carbon dioxide emissions, leading industrial enterprises are researching and developing carbon reduction strategies. One such strategy is the technology of capturing and processing carbon dioxide emitted from "chimneys," namely Carbon Capture and Storage (CCS). This technology involves capturing, transporting, and storing large quantities of carbon dioxide emitted during industrial processes, and can be used for enhancing the recovery of oil or natural gas. However, in China, not only are storage sites difficult to find, but considerations such as the geological stability after storage and the impact on the ecosystem also make this technology difficult to apply.

[0004] Another technology is carbon capture and utilization (CCU). The large amounts of carbon dioxide generated in processes across various industrial sectors, including the petrochemical industry, can be used as a carbon source for producing fuels and high-value-added chemicals in a variety of carbon dioxide-related environmental technologies. Therefore, for the sustainable development of industries in various sectors, carbon dioxide capture and utilization technologies are particularly important for fundamentally reducing carbon dioxide emissions while simultaneously recycling them to produce basic petrochemical oils such as ethylene.

[0005] Previous methods for converting captured carbon dioxide into hydrocarbons typically involved using a copper catalyst to hydrogenate the carbon dioxide into carbon monoxide and water, with the carbon monoxide being utilized. However, this technology requires the use of large quantities of expensive hydrogen, necessitating the simultaneous construction of hydrogen production and high-purity hydrogen capture facilities, which presents an economic disadvantage.

[0006] Therefore, there is a need for a method and apparatus for preparing hydrocarbons that utilizes easily processed raw materials to convert carbon dioxide into carbon monoxide with excellent conversion rates, thereby reducing carbon dioxide emissions while efficiently generating high-value-added hydrocarbons. Summary of the Invention

[0007] (a) Technical problems to be solved The purpose of this invention is to provide a method and apparatus for preparing hydrocarbons using carbon dioxide captured from gases generated from the atmosphere or external processes.

[0008] Furthermore, another object of the present invention is to provide a method and apparatus for preparing hydrocarbons using only easily processed raw materials.

[0009] Furthermore, another object of the present invention is to provide a method and apparatus for preparing hydrocarbons that can convert carbon dioxide into carbon monoxide with excellent conversion efficiency without producing byproducts.

[0010] (II) Technical Solution The method for preparing hydrocarbons according to the present invention comprises the following steps: (S1) separating a first stream containing carbon dioxide from a feed gas; (S2) subjecting the carbon dioxide contained in the first stream and an external carbon source to a reverse boudouard reaction to convert it into a first mixed gas containing carbon monoxide; (S3) subjecting a predetermined volume of the first mixed gas to a water-gas shift reaction to convert it into a second mixed gas; (S4) separating the second mixed gas into a second stream containing carbon dioxide and a third stream containing hydrogen; and (S5) subjecting the remaining first mixed gas that was not converted in step (S3) and the third stream to a Fischer-Tropsch synthesis reaction to generate hydrocarbons.

[0011] According to one implementation scheme, steps (S1) and (S4) can be performed by the same carbon dioxide separation unit.

[0012] Steps (S1) to (S5) according to one implementation scheme can be used as unit processes, and the unit process can be repeated more than twice.

[0013] Prior to step (S3) according to one embodiment, a step of purifying the first mixed gas may be further included.

[0014] Prior to step (S5) according to one embodiment, a further step may be included in which the remaining unconverted first mixed gas in step (S3) and the third stream separated in step (S4) are mixed to prepare a third mixed gas.

[0015] The reverse Boudouar reaction according to step (S2) of one embodiment can be carried out at a temperature of 500°C to 1000°C.

[0016] The water-gas shift reaction according to step (S3) of one implementation scheme can be carried out at a temperature of 100°C to 500°C and a pressure of 10 bar to 50 bar.

[0017] The Fischer-Tropsch synthesis reaction according to step (S5) of one embodiment can be carried out at a temperature of 150°C to 500°C and a pressure of 10 bar to 50 bar.

[0018] The hydrocarbon preparation apparatus according to the present invention comprises: a first carbon dioxide separation unit that separates a first stream containing carbon dioxide from a feed gas; a reverse Boudouar reactor that converts the carbon dioxide contained in the first stream and an external carbon source into a first mixed gas containing carbon monoxide; a water-gas shift reactor that converts a predetermined volume of the first mixed gas into a second mixed gas; a second carbon dioxide separation unit that separates the second mixed gas into a second stream containing carbon dioxide and a third stream containing hydrogen; and a Fischer-Tropsch synthesis reactor into which the remaining unconverted first mixed gas from the water-gas shift reactor and the third stream separated by the second carbon dioxide separation unit are added to generate hydrocarbons.

[0019] According to one embodiment, the first carbon dioxide separation unit and the second carbon dioxide separation unit may be the same.

[0020] The hydrocarbon preparation apparatus according to one embodiment may further include a refining unit for refining the first mixed gas.

[0021] The hydrocarbon preparation apparatus according to one embodiment may further include a mixing unit that mixes the unconverted remaining first mixed gas in the water-gas shift reactor with the third feed stream separated by the second carbon dioxide separation unit.

[0022] (III) Beneficial Effects The method and apparatus for preparing hydrocarbons according to the present invention can utilize carbon dioxide captured from gases generated in the atmosphere or external processes to prepare high-value-added hydrocarbons.

[0023] The method and apparatus for preparing hydrocarbons according to the present invention can convert carbon dioxide into carbon monoxide with excellent conversion rate without producing byproducts, and is therefore economical.

[0024] The method and apparatus for preparing hydrocarbons according to the present invention can reduce the concentration of carbon dioxide in the atmosphere.

[0025] The method and apparatus for preparing hydrocarbons according to the present invention require less equipment cost compared to conventional methods, thereby increasing the yield of carbon dioxide derivatives. Attached Figure Description

[0026] Figure 1 This is a schematic diagram showing an apparatus for preparing hydrocarbons according to the present invention.

[0027] Figure 2 This is a schematic diagram illustrating a hydrocarbon preparation apparatus using the same carbon dioxide separation unit according to the present invention. Detailed Implementation

[0028] Unless otherwise specified, the singular form of the terms used in this specification may be interpreted to also include the plural form.

[0029] The numerical ranges used in this specification include lower and upper limits, as well as all values ​​within that range, all values ​​defined therein, and all possible combinations of upper and lower limits of numerical ranges defined in different forms. Unless otherwise specifically defined in this specification, values ​​outside the defined numerical range that may arise due to experimental error or rounding are also included within the defined numerical ranges.

[0030] The terms “comprising” or “including” used in this specification are open-ended expressions that have the same meaning as expressions such as “possessing,” “containing,” “having,” “characterized in,” etc., and do not exclude elements, materials, or processes not further listed.

[0031] Unless otherwise defined, the units of % used in this specification refer to weight unless otherwise specified.

[0032] The term "carbon dioxide conversion rate" mentioned in this specification can refer to the molar ratio of carbon dioxide converted to carbon monoxide to the carbon dioxide added to the process.

[0033] Conventional methods for converting carbon dioxide into hydrocarbons typically involve hydrogenation using a copper catalyst to convert carbon dioxide into carbon monoxide and water, followed by the utilization of the converted carbon monoxide. However, this technology is burdened by the requirement to use large quantities of expensive hydrogen. Hydrogen production and high-purity hydrogen capture equipment are necessary for this process, thus presenting an economic disadvantage. Therefore, the inventors of this invention have devised a method and apparatus for preparing high-value-added hydrocarbons from carbon dioxide captured from the atmosphere or process gases at a lower cost and higher efficiency than before. The hydrocarbon preparation method and apparatus of this invention are described in detail below.

[0034] The present invention provides a method for preparing hydrocarbons, the method comprising the following steps: (S1) separating a first stream containing carbon dioxide from a feed gas; (S2) subjecting the carbon dioxide contained in the first stream to a reverse Boudouar reaction with an external carbon source to convert it into a first mixed gas containing carbon monoxide; (S3) subjecting a predetermined volume of the first mixed gas to a water-gas shift reaction to convert it into a second mixed gas; (S4) separating the second mixed gas into a second stream containing carbon dioxide and a third stream containing hydrogen and carbon monoxide; and (S5) subjecting the remaining first mixed gas that was not converted in step (S3) and the third stream separated in step (S4) to a Fischer-Tropsch synthesis reaction to generate hydrocarbons.

[0035] Step (S1) is the step of separating a first stream containing carbon dioxide from the feed gas.

[0036] In one example, in step (S1), the separation of the first feed stream containing carbon dioxide from the feed gas can be performed by a first carbon dioxide separation unit. In one example, the first carbon dioxide separation unit can be an amine scrubber. Typically, an amine scrubber can separate carbon dioxide, hydrogen sulfide, and other components from gas vapor by binding and removing carbon dioxide with amine substances, and recover gases containing hydrogen, carbon monoxide, or inert gases. Therefore, carbon dioxide can be separated from the feed gas using an amine scrubber. Specifically, the amine scrubber can separate carbon dioxide from the feed gas through a reaction according to the following reaction formula 1.

[0037] [Reaction Formula 1] 2RNH2+CO2↔RNHCOO - +RNH3 + As another example, the first carbon dioxide separation unit may be a carbon capture and storage unit (CCS). When the CCS unit is used for carbon dioxide separation, it may utilize one or more adsorbents selected from calcium oxide, calcium hydroxide, dolomite, limestone, or natural alkali to separate carbon dioxide from the feed gas.

[0038] In one example, in step (S1), the feed gas can be the atmosphere or exhaust gas generated from an external process, but there are no particular limitations as long as it contains carbon dioxide. Furthermore, the external process can refer to any process that can generate carbon dioxide in various industrial sectors.

[0039] Step (S2) involves subjecting the carbon dioxide contained in the first feed stream separated in step (S1) and an external carbon source to a reverse Boudouar reaction to convert it into a first mixed gas containing carbon monoxide. The reverse Boudouar reaction may be accompanied by the following reaction formula 2.

[0040] [Reaction 2] C + CO₂ → 2CO In one instance, the external carbon source may be selected from one or more of graphite, pyrolysis char, biochar, and activated carbon, but is not limited thereto.

[0041] In one example, the reverse Boudouar reaction in step (S2) can be carried out at a temperature of 600°C to 1000°C, specifically 650°C to 900°C, more specifically 700°C to 800°C, and at a pressure of 0.5 bar to 30 bar, specifically 1 bar to 15 bar, more specifically 2 bar to 5 bar, but is not limited thereto.

[0042] In one example, the reverse Boudouar reaction in step (S2) can be carried out in a fixed-bed reactor. Under these conditions, even if the first feed stream contains carbon dioxide of low purity, carbon dioxide can be converted to carbon monoxide with high efficiency, but this is not a limitation as long as the objectives of the invention can be achieved.

[0043] In one example, the method for preparing hydrocarbons according to the present invention may further include a step of purifying the first mixed gas. In addition to carbon monoxide, the first mixed gas may also contain one or more impurities selected from tar, sulfur, nitrogen, chlorine, and heavy metals. Specifically, the first mixed gas may contain water-soluble impurities such as H2S, HCl, COS, HOCl, and NH3, and non-water-soluble impurities such as tar and heavy metals. These impurities contained in the first mixed gas may induce deactivation of the catalyst used in the present invention, reducing the efficiency of subsequent processes. Therefore, the impurities can be removed by purifying the first mixed gas, thereby improving the efficiency of the entire process.

[0044] In one example, the step of purifying the first mixed gas can be performed by one or more combinations selected from, but not limited to, passing through a high-pressure dust filter, water washing, alkaline solution washing, and passing through a ceramic filter. Water washing or alkaline solution washing can remove water-soluble impurities such as H2S, HCl, COS, HOCl, and NH3 contained in the first mixed gas. Passing the first mixed gas through a ceramic filter or dust filter can remove non-water-soluble impurities such as tar and heavy metals, as well as dust.

[0045] Step (S3) involves subjecting a predetermined volume of the first mixed gas to a water-gas shift reaction to convert it into a second mixed gas. Through this water-gas shift reaction, the hydrogen to carbon monoxide ratio in the first mixed gas is adjusted, allowing for smooth subsequent processes, namely the Fischer-Tropsch synthesis reaction. Specifically, the water-gas shift reaction can involve the carbon monoxide and water contained in the first mixed gas reacting as shown in Reaction Equation 3 below to convert it into the second mixed gas.

[0046] [Reaction 3] CO + H₂O → H₂ + CO₂ In one example, the specified volume is based on the total volume of the first mixed gas, and the lower limit can be 10% or more, 20% or more, 30% or more, 40% or more, or 45% or more, and the upper limit can be less than 100% or less, 80% or less, 70% or less, 60% or less, or 55% or less. Specifically, it can be 10% to 90% of volume, 20% to 80% of volume, 30% to 70% of volume, 40% to 60% of volume, or 45% to 55% of volume, but is not limited thereto.

[0047] In one instance, the water-gas shift reaction can be carried out in a water-gas shift catalyst containing Cu, Zn, or a combination thereof. As a specific example, it can be carried out in a water-gas shift catalyst with Cu and Zn supported on an alumina support, but is not limited thereto.

[0048] In one example, the water-gas shift reaction can be carried out at a temperature of 100°C to 500°C, specifically 125°C to 300°C, more specifically 150°C to 200°C, and at a pressure of 20 bar to 80 bar, specifically 25 bar to 60 bar, more specifically 30 bar to 40 bar.

[0049] In one instance, the second gas mixture may contain hydrogen and carbon dioxide.

[0050] Step (S4) is the step of separating the second mixed gas into a second stream containing carbon dioxide and a third stream containing hydrogen.

[0051] In one example, in step (S4), separating the second mixed gas into a second stream containing carbon dioxide and a third stream containing hydrogen can be performed by a second carbon dioxide separation unit. The above description of the first carbon dioxide separation unit can be equally applied to the description of the second carbon dioxide separation unit to the extent necessary.

[0052] In one example, step (S4) can be performed using the same carbon dioxide separation unit as step (S1). In this case, not only is the carbon dioxide generated in step (S3) not emitted into the atmosphere, but it can also be recycled to participate in the reverse Boudouar reaction of step (S2), thereby significantly improving the carbon dioxide conversion rate and ensuring economic efficiency.

[0053] In one example, when step (S4) is performed using the same first carbon dioxide separation unit as step (S1), the hydrocarbon preparation method of the present invention can be a unit process consisting of steps (S1) to (S5) and repeated more than twice. By repeating the unit process more than twice, carbon dioxide is continuously converted into hydrocarbons, significantly improving the carbon dioxide conversion rate. Furthermore, when the hydrocarbon preparation method of the present invention further includes additional steps besides steps (S1) to (S5), the unit process can naturally also include these additional steps.

[0054] Step (S5) involves subjecting the remaining unconverted first mixed gas from step (S3) and the separated third feed stream from step (S4) to a Fischer-Tropsch synthesis reaction to generate hydrocarbons. Specifically, the carbon monoxide and hydrogen contained in the first mixed gas react with the hydrogen contained in the third feed stream to generate hydrocarbons. The Fischer-Tropsch synthesis reaction may be accompanied by the following reaction formula 4.

[0055] [Reaction 4] nCO + 2nH2 → C n H 2n +nH2O In one example, the Fischer-Tropsch synthesis reaction in step (S5) can be carried out under a Fischer-Tropsch catalyst containing cobalt, nickel, or iron. The support can include alumina, silica, titanium dioxide, etc., and the co-catalyst can include noble metals such as Pt, Ru, and Re.

[0056] In one example, the Fischer-Tropsch synthesis reaction in step (S5) can be carried out at a temperature of 100°C to 500°C, specifically 200°C to 350°C, and at a pressure of 10 bar to 50 bar, specifically 20 bar to 40 bar. When the above ranges are met, it has the effect of producing excellent yields of hydrocarbons.

[0057] In one example, prior to step (S5), the method for preparing hydrocarbons according to the invention may further include a step of mixing the third feed stream separated in the second carbon dioxide separation unit with the remaining unconverted first mixed gas from step (S3) to prepare a third mixed gas. At this point, the single feed stream containing the third mixed gas can be fed into the Fischer-Tropsch synthesis reactor to undergo a Fischer-Tropsch synthesis reaction.

[0058] In one example, the molar ratio (m) of hydrogen to carbon monoxide in the third mixed gas is... H2 / m CO The value can be 1 to 10, specifically 1.3 to 5, or more specifically 1.8 to 2.5. When the above range is met, the efficiency of the Fischer-Tropsch synthesis reaction can be improved.

[0059] In one example, the method for preparing hydrocarbons according to the present invention may further include a separation step for separating the hydrocarbons generated in step (S5). In one example, the method for separating the hydrocarbons generated in step (S5) is not particularly limited as long as it is a method known in the art, but distillation may be an example.

[0060] In another aspect, the present invention provides a hydrocarbon preparation apparatus, comprising: a first carbon dioxide separation unit that separates a first stream containing carbon dioxide from a feed gas; a reverse Boudouar reactor that converts the carbon dioxide contained in the first stream and an external carbon source into a first mixed gas containing carbon monoxide; a water-gas shift reactor that converts a predetermined volume of the first mixed gas into a second mixed gas; a second carbon dioxide separation unit that separates the second mixed gas into a second stream containing carbon dioxide and a third stream containing hydrogen; and a Fischer-Tropsch synthesis reactor into which the remaining unconverted first mixed gas from the water-gas shift reactor and the third stream separated by the second carbon dioxide separation unit are added to generate hydrocarbons. The hydrocarbon preparation apparatus according to the present invention, due to the above-described configuration, can efficiently and economically prepare hydrocarbons and can significantly reduce carbon dioxide emissions.

[0061] The description of methods for preparing hydrocarbons can be applied equally to the description of apparatuses for preparing hydrocarbons, to the extent that it may be repeated.

[0062] refer to Figure 1After the feed gas 100 is introduced into the first carbon dioxide separation unit 10, a first feed stream 120 containing carbon dioxide can be separated from the feed gas 100. The first feed stream 120 separated by the first carbon dioxide separation unit 10 and the external carbon source 130 flow into the reverse Boudouar reactor 20, where they can be converted into a first mixed gas 140 containing carbon monoxide.

[0063] In one example, the hydrocarbon preparation apparatus of the present invention may further include a refining unit 25. Located between the reverse Boudouar reactor 20 and the water-gas shift reactor 30, the refining unit removes impurities from the first mixed gas 140 converted from the reverse Boudouar reactor 20 and introduces the first mixed gas (150, 160) with the impurities removed into the water-gas shift reactor 30. Specifically, the refining unit 25 includes a liquid ejector that receives the first mixed gas 140 from the reverse Boudouar reactor 20 and contacts it with a weakly alkaline solution containing water or an alkaline compound such as sodium carbonate, thereby removing water-soluble impurities such as H2S, HCl, COS, HOCl, and NH3. Furthermore, a high-pressure dust collector, including ceramic filters, can be used to remove dust, thereby removing non-water-soluble impurities such as tar and heavy metals.

[0064] In one example, the refining unit may include multiple units (25-1, 25-2), specifically, the multiple units may include a scrubber and an adsorption bed. When this condition is met, water-soluble and insoluble impurities can be removed in stages, thus improving refining efficiency.

[0065] Through a material flow separation device, a specified volume of the first mixed gas (150, 160) and water 180 flows into the water-gas shift reactor 30, whereby they can be converted into a second mixed gas 190 containing hydrogen and carbon dioxide.

[0066] The second carbon dioxide separation unit 40 can separate the second mixed gas 190 into a second stream 200 containing carbon dioxide and a third stream 210 containing hydrogen. Of course, when the hydrocarbon preparation apparatus of the present invention further includes the purification unit, the second mixed gas, from which the impurities are removed, can be separated.

[0067] refer to Figure 1 and Figure 2 In one example, the first carbon dioxide separation unit 10 and the second carbon dioxide separation unit 40 can be identical. In this case, not only can the carbon dioxide separated from the second mixed gas 190 not be emitted into the atmosphere, but the carbon dioxide conversion rate can also be significantly improved through recycling, and the process can be operated using a single carbon dioxide separation unit, thereby ensuring economic efficiency.

[0068] The unconverted first mixed gas 170 in the water-gas shift reactor 30 and the third feed stream 210 separated by the second carbon dioxide separation unit 40 are introduced into the Fischer-Tropsch synthesis reactor 50 and converted into hydrocarbons 230 through the Fischer-Tropsch synthesis reaction, which can be recovered as high-value-added oil fractions.

[0069] In one example, the hydrocarbon preparation apparatus of the present invention may further include a mixing unit 45, which mixes the remaining unconverted first mixed gas 170 in the water-gas shift reactor 30 with the third feed stream 210 separated by the second carbon dioxide separation unit 40 to prepare a third mixed gas 220. The third mixed gas 220 can then be supplied to the Fischer-Tropsch synthesis reactor 50 and converted into hydrocarbons.

[0070] In one example, the hydrocarbon preparation apparatus of the present invention may further include a separation unit (not shown) for separating the hydrocarbons generated in the Fischer-Tropsch synthesis reactor. In one example, the separation unit may be a distillation column, but is not limited thereto.

[0071] The following examples illustrate in more detail the method and apparatus for preparing hydrocarbons according to the present invention. However, these examples are merely illustrative of the invention and are not intended to limit it; the invention can be implemented in various forms. Furthermore, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Moreover, the terminology used in this invention is merely for the purpose of effectively describing specific embodiments and is not intended to limit the invention.

[0072] Gas composition analysis methods Gas composition analysis was performed using gas chromatography (GC), and the total amount of gas was confirmed using a gas meter. Specifically, quantification was performed using GC to calculate the selectivity of different gases, and the composition of each gas was analyzed by measuring the total amount of gas confirmed using the gas meter.

[0073] Example 1. Separation of carbon dioxide The feed gas generated during the coal gasification process is added to the first amine scrubber to capture carbon dioxide under conditions of 50°C, 15 bar and 12% by weight of ammonia solution. Then, the ammonia solution containing the captured carbon dioxide is introduced into the second amine scrubber to separate into ammonia solution and carbon dioxide at 100°C, and the carbon dioxide is recovered as the first feed stream.

[0074] 2. Reverse Boudouard reaction The recovered first feed stream was continuously fed into a fixed-bed reactor filled with Ni / Al₂O₃ catalyst and 5 kg of high-purity graphite. Carbon dioxide was converted to carbon monoxide via a reverse Boudouar reaction. A first mixed gas containing carbon monoxide was captured, and the composition of its main components is shown in Table 1 below. The reverse Boudouar reaction was conducted under N₂ gas at 750 °C, a CO₂ flow rate of 2.33 Nl / min, and a CO₂ concentration of 2.0 L / g. cat The test was conducted for 2 hours at an air velocity of h.

[0075] [Table 1] (N / D: Not Detected) 3. Water-gas shift reaction The first mixed gas is passed sequentially through an adsorption tower and a scrubber made of calcium oxide. Then, 66.7% of the purified first mixed gas and purified water are introduced into a water-gas shift unit. Under the influence of a Cu / Zn / Al2O3 catalyst, the mixture is heated at 165°C, 35 bar, and a space velocity of 1.4 L / g. cat Under the conditions of ·h, a water-gas shift reaction is carried out to convert it into a second mixed gas containing carbon dioxide and hydrogen. The composition of the main components is shown in Table 2 below.

[0076] [Table 2] 4. Separation of carbon dioxide and hydrogen The second mixed gas is added to the first amine scrubber, where carbon dioxide is captured under the same conditions as when capturing carbon dioxide from the feed gas. Then, the ammonia solution containing the captured carbon dioxide is introduced into the second amine scrubber, where it is separated into an ammonia solution and carbon dioxide at 100°C. The streams containing carbon dioxide and hydrogen are recovered separately.

[0077] 5. Gas mixing The remaining first mixed gas not used in the water-gas shift reaction and the hydrogen-containing stream separated from the second mixed gas are introduced into the gas mixing unit and mixed at 200°C to generate a third mixed gas.

[0078] 6. Fischer-Tropsch synthesis reaction The third mixed gas is supplied to the Fischer-Tropsch synthesis reactor, under a Co(10%) / ZrO2 catalyst, at a concentration of 1.6 L / g. cat The Fischer-Tropsch synthesis reaction was carried out at a space velocity of h, 245 °C, and 35 bar, and hydrocarbons were recovered. The composition of the main components is shown in Table 3 below.

[0079] [Table 3] As shown in Tables 1 to 3, the hydrocarbon preparation method according to the embodiments can safely convert carbon dioxide into hydrocarbons using only easily handled carbon and water without the need for high-purity hydrogen. Furthermore, considering that carbon dioxide is converted to carbon monoxide with a high conversion rate and without byproducts for recycling, it can be confirmed that approximately 100% carbon dioxide conversion can be achieved, thus ensuring economic efficiency.

[0080] As described above, the present invention has been illustrated with specific content and limited embodiments, but this is only provided to help to understand the present invention more fully. The present invention is not limited to the above embodiments, and those skilled in the art can make various modifications and variations based on these descriptions.

[0081] Therefore, the concept of this invention should not be limited to the illustrated embodiments, and all contents of the claims of this invention and those equivalent to or having equivalent variations thereof are within the scope of the concept of this invention.

[0082] [Explanation of reference numerals in the attached figures] 10 First Carbon Dioxide Separation Unit 20 Reverse Boudouard Reactor 25-1, 25-2 Refining Unit 30 Water-Gas Shift Reactor 40 Second carbon dioxide separation unit 45 Hybrid Units 50 Fischer-Tropsch synthesis reactor 100 feed gas 110 Feed gas for separating carbon dioxide 120 First Material Flow 130 External carbon sources 140 First Mixed Gas 150, 160 Refined First Mixture 170 Remaining first mixture 180 water 190 Second Mixed Gas 200 Second material flow 210 Third Material Flow 220 Third Mixed Gas 230 Hydrocarbons

Claims

1. A method for preparing a hydrocarbon, wherein, The preparation method includes the following steps: (S1) Separate the first feed stream containing carbon dioxide from the feed gas; (S2) The carbon dioxide contained in the first feed stream and the external carbon source are subjected to the reverse Boudouar reaction to convert it into a first mixed gas containing carbon monoxide. (S3) A specified volume of the first mixed gas is subjected to a water-gas shift reaction to convert it into a second mixed gas; (S4) Separate the second mixed gas into a second stream containing carbon dioxide and a third stream containing hydrogen; and (S5) The remaining first mixed gas that was not converted in step (S3) and the third feed stream are subjected to a Fischer-Tropsch synthesis reaction to produce hydrocarbons.

2. The method for preparing hydrocarbons according to claim 1, wherein, Steps (S1) and (S4) are performed using the same carbon dioxide separation unit.

3. The method for preparing hydrocarbons according to claim 2, wherein, Using steps (S1) to (S5) as a unit process, the unit process is repeated more than twice.

4. The method for preparing hydrocarbons according to claim 1, wherein, Prior to step (S3), the preparation method further includes a step of purifying the first mixed gas.

5. The method for preparing hydrocarbons according to claim 1, wherein, Prior to step (S5), the preparation method further includes the step of mixing the remaining first mixed gas that was not converted in step (S3) with the third feed stream that was separated in step (S4) to prepare a third mixed gas.

6. The method for preparing hydrocarbons according to claim 1, wherein, The reverse Boudouar reaction in step (S2) is carried out at a temperature of 500°C to 1000°C.

7. The method for preparing hydrocarbons according to claim 1, wherein, The water-gas shift reaction in step (S3) is carried out at a temperature of 100°C to 500°C and a pressure of 10 bar to 50 bar.

8. The method for preparing hydrocarbons according to claim 1, wherein, The Fischer-Tropsch synthesis reaction in step (S5) is carried out at a temperature of 150°C to 500°C and a pressure of 10 bar to 50 bar.

9. An apparatus for preparing hydrocarbons, wherein, The preparation apparatus includes: A first carbon dioxide separation unit separates a first feed stream containing carbon dioxide from the feed gas; A reverse Boudouar reactor, wherein the reverse Boudouar reactor converts the carbon dioxide contained in the first feed stream and an external carbon source into a first mixed gas containing carbon monoxide; A water-gas shift reactor, wherein the water-gas shift reactor converts a specified volume of a first mixed gas into a second mixed gas; A second carbon dioxide separation unit separates the second mixed gas into a second stream containing carbon dioxide and a third stream containing hydrogen; and A Fischer-Tropsch synthesis reactor, wherein the unconverted remaining first mixed gas from the water-gas shift reactor and the third feed stream separated by the second carbon dioxide separation unit are added to generate hydrocarbons.

10. The hydrocarbon preparation apparatus according to claim 9, wherein, The first carbon dioxide separation unit and the second carbon dioxide separation unit are identical.

11. The hydrocarbon preparation apparatus according to claim 9, wherein, The preparation apparatus further includes a refining unit for refining the first mixed gas.

12. The hydrocarbon preparation apparatus according to claim 9, wherein, The preparation apparatus further includes a mixing unit that mixes the unconverted remaining first mixed gas in the water-gas shift reactor with the third feed stream separated by the second carbon dioxide separation unit.

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