WO2024058368A1

WO2024058368A1 - Iron-based catalyst, method for producing same, and hydrocarbon production methods using same

Info

Publication number: WO2024058368A1
Application number: PCT/KR2023/008723
Authority: WO
Inventors: 천동현; 윤민혜; 임근배
Original assignee: 한국에너지기술연구원
Priority date: 2021-10-21
Filing date: 2023-06-23
Publication date: 2024-03-21
Also published as: KR20230057947A

Abstract

An iron-based catalyst according to various embodiments of the present invention comprises iron hydroxide, iron oxide, and iron carbide, wherein based on the number of iron atoms contained in the iron-based catalyst being 100%, the number of iron atoms contained in the iron hydroxide corresponds to 13 to 80%, the number of iron atoms contained in the iron oxide corresponds to 1 to 5%, and the number of iron atoms contained in the iron carbide corresponds to 21 to 85%.

Description

Iron-based catalyst, method for producing the same, and method for producing hydrocarbons using the same

Various embodiments of the present invention relate to an iron-based catalyst, a method for producing the same, and a method for producing hydrocarbons using the same. More specifically, it relates to an iron-based catalyst capable of producing hydrocarbons with a carbon number of 5 or more with high selectivity by optimizing the phase fractions of iron oxides, iron oxides, and iron carbides, a method for producing the same, and a method for producing hydrocarbons using the same.

While the demand for oil has been steadily increasing since industrialization, oil reserves are limited, so a point (peak oil) will inevitably arrive when oil supply cannot keep up with demand, and many scholars believe that This peak oil has already arrived or is predicted to arrive soon. Therefore, in order to minimize the economic/social crisis and shock that will occur after the arrival of peak oil, the development of technology to reduce dependence on crude oil and the development of synthetic petroleum manufacturing technology to supplement the shortage of crude oil by manufacturing raw materials other than crude oil are necessary. Interest in this is growing.

Indirect coal liquefaction, one of the representative synthetic petroleum production technologies, is a process that converts synthetic gas (H ₂ + CO) obtained through coal gasification and purification into liquid synthetic petroleum through the Fischer-Tropsch synthesis reaction. It is a very promising technology in terms of clean use of coal and the ability to obtain high value-added products. In particular, coal has abundant reserves, is evenly distributed throughout the world, and has the advantage of being cheap.

The Fischer-Tropsch synthesis reaction first began in 1923 when German chemists Fischer and Tropsch developed a technology to produce synthetic fuel from synthesis gas by gasifying coal. The Fischer-Tropsch synthesis reaction is a reaction that uses a catalyst to convert synthesis gas into hydrocarbons. The catalyst used here has a higher selectivity, which increases the productivity of hydrocarbons with 5 or more carbon atoms, which is a general indicator of productivity, and overall carbon efficiency. can increase.

Group VIII metal materials such as iron (Fe), cobalt (Co), nickel (Ni), and ruthenium (Ru) have been reported as substances that are active in the Fischer-Tropsch synthesis reaction. Among them, iron (Fe)-based catalysts are especially suitable for the Fischer-Tropsch synthesis reaction linked to indirect coal liquefaction due to their low manufacturing cost, excellent performance, and activity in water-gas shift (WGS). Shows advantages.

Iron carbide is known to be the main active species in iron-based catalysts, and studies have been mainly conducted to increase the amount of iron-based carbide in the catalyst to improve catalyst performance. However, because iron-based catalysts have complex structures of various carbides/oxides (hydroxides) under active conditions, existing research to simply increase the amount of iron-based carbides in the catalyst had limitations in improving the performance of the catalyst. In particular, conventional research has limitations in suppressing the production of CO ₂ , CH ₄ and C ₂ -C ₄ hydrocarbons, which are unnecessary by-products in the Fischer-Tropsch synthesis reaction, and increasing the productivity of (C ₅₊ ) hydrocarbons with a carbon number of 5 or more. There was.

The present invention was created in consideration of the above problems, and its purpose is to provide an iron-based catalyst that can significantly increase the productivity of hydrocarbons with a carbon number of 5 or more.

Additionally, the purpose of the present invention is to provide a method for producing an iron-based catalyst with excellent catalytic performance that can be usefully applied to Fischer-Tropsch synthesis reactions.

The iron-based catalyst according to various embodiments of the present invention includes iron oxide, iron oxide, and iron carbide, and the number of iron atoms contained in the iron oxide is 13 to 80% with respect to 100% of the iron atom contained in the iron-based catalyst. , 1 to 5% of the iron atoms contained in the iron oxide, and 21 to 85% of the iron atoms contained in the iron carbide.

The method for producing an iron-based catalyst according to various embodiments of the present invention includes preparing a mixed solution by mixing an aqueous solution of a salt of a metal selected from the group consisting of copper, cobalt, manganese, and a combination thereof and an aqueous solution of iron nitrate, and adding the mixed solution to the aqueous solution of iron nitrate. A first precursor obtaining step of obtaining a first precursor by adding a basic aqueous solution; A second precursor slurry forming step of forming a second precursor slurry by adding at least one oxide of silicon oxide, aluminum oxide, zirconium oxide, or chromium oxide and an aqueous solution of at least one of an alkali metal or an alkaline earth metal to the first precursor; A third precursor production step of drying and calcining the second precursor slurry to produce a third precursor; And an activation step of activating the third precursor by heat treatment, wherein the third precursor is activated at a H ₂ /CO volume ratio of 1 to 3, GHSV 1 to 12 NL/g _(cat) /h, It is characterized by heat treatment under the conditions of a temperature of 230 to 290 ° C and a pressure of 0.5 to 1.5 MPa.

A method for producing hydrocarbons according to various embodiments of the present invention includes preparing an iron-based catalyst; and producing hydrocarbons by performing a Fischer-Tropsch synthesis reaction using the iron-based catalyst, wherein the iron-based catalyst includes iron oxide, iron oxide, and iron carbide, and iron atoms contained in the iron-based catalyst. Based on 100% of the number, the number of iron atoms contained in the iron oxide is 13 to 80%, the number of iron atoms contained in the iron oxide is 1 to 5%, and the number of iron atoms contained in the iron carbide is 21 to 85%. It is characterized by

The iron-based catalyst of the present invention optimizes the phase fraction of iron oxide, iron oxide, and iron carbide to produce a high content of hydrocarbons with carbon number of 5 or more (C ₅₊ hydrocarbons) of 80 wt% or more and wax (C ₁₉₊ hydrocarbons) of 48 wt% or more. It can be produced selectively.

In general, when the volume ratio of H ₂ /CO increases in the Fischer-Tropsch synthesis reaction, hydrogenation, the main mechanism of chain termination, is promoted, chain growth is not performed well, and selectivity for wax is low. Furthermore, when using the iron-based catalyst with the optimized phase fraction of the present invention, chain growth is promoted even under Fischer-Tropsch reaction conditions with a high hydrogen ratio, thereby increasing wax productivity.

In addition, the wax produced using the iron-based catalyst of the present invention is mostly paraffin, has a low olefin content, and does not require hydrogenation.

The iron-based catalyst of the present invention can maintain excellent activity for a long time under low-temperature Fischer-Tropsch synthesis reaction conditions.

Figure 1 shows the results of analyzing the phase fraction of the activated iron-based catalyst prepared by the method of Example 1 by Mössbauer spectroscopy.

Figure 2 shows the results of analyzing the phase fraction of the activated iron-based catalyst prepared by the method of Example 2 by Mössbauer spectroscopy.

Figure 3 shows the results of analyzing the phase fraction of the activated iron-based catalyst prepared by the method of Example 12 by Mössbauer spectroscopy.

Figure 4 shows the results of analyzing the phase fraction of the activated iron-based catalyst prepared by the method of Example 15 by Mössbauer spectroscopy.

Figure 5 shows the results of analyzing the phase fraction of the activated iron-based catalyst prepared by the method of Comparative Example 2 by Mössbauer spectroscopy.

Figure 6 shows the results of long-term performance evaluation of the activated iron-based catalyst prepared by the method of Example 9 under Fischer-Tropsch synthesis reaction conditions.

Hereinafter, various embodiments of this document are described with reference to the attached drawings. The examples and terms used herein are not intended to limit the technology described in this document to specific embodiments, and should be understood to include various modifications, equivalents, and/or substitutes for the examples.

철계 촉매iron-based catalyst

The iron-based catalyst according to various embodiments of the present invention is a catalyst for Fischer-Tropsch synthesis reaction, and is an iron-based catalyst that can significantly increase the productivity of hydrocarbons with a carbon number of 5 or more and hydrocarbons (waxes) with a carbon number of 19 or more.

The iron-based catalyst of the present invention includes iron hydroxide, iron oxide, and iron carbide. More specifically, with respect to 100% of the iron atoms contained in the iron-based catalyst, the number of iron atoms contained in iron oxide is 13 to 80%, the number of iron atoms contained in iron oxide is 1 to 5%, and the number of iron atoms contained in iron carbide is 100%. It may contain 21 to 85%. If each phase is outside the above range, the selectivity for hydrocarbon C ₅₊ and/or C ₁₉₊ hydrocarbons having 5 or more carbon atoms may be lowered. For example, if each phase is outside the above range, the selectivity for C ₅₊ hydrocarbons may be lowered to less than 80 wt% or the selectivity for C ₁₉ hydrocarbons may be lowered to less than 48 wt%. In other words, the iron-based catalyst of the present invention optimizes the phase fraction of iron oxide, iron oxide, and iron carbide to produce more than 80 wt% of C ₅₊ hydrocarbons with a carbon number of 5 or more and 48 wt% of wax (C ₁₉₊ hydrocarbon) with a carbon number of 19 or more. It can be produced with a high selectivity of over %.

The iron oxide may be ferrihydrite. Ferryhydrite can be expressed by the chemical formula FeOOH· n H ₂ O (0<n<1).

The iron oxide may be magnetite (Fe ₃ O ₄ ).

The iron carbide may be at least one selected from the group consisting of c-carbide (Fe ₅ C ₂ ) and ε'-carbide (Fe _2.2 C). Preferably, the iron carbide may include both c-carbide (Fe ₅ C ₂ ) and ε'-carbide (Fe _2.2 C). At this time, with respect to 100% of the iron atoms contained in the iron-based catalyst, the number of iron atoms contained in c-carbide (Fe ₅ C ₂ ) is 21 to 75% and the number of iron atoms contained in ε'-carbide (Fe _2.2 C) It may contain 6 to 13%.

The iron-based catalyst of the present invention has a H ₂ /CO volume ratio of 1 to 5, a space velocity (GHSV) of 1 to 13 NL/g _(cat) /h, a temperature of 230 to 290 ° C., and a pressure of 0.5 to 2.0 MPa. Under Ropsch reaction conditions, the selectivity for hydrocarbons (C ₅₊ ) having 5 or more carbon atoms may be 80 wt% or more and the selectivity for waxes (C ₁₉₊ hydrocarbons) having 19 or more carbon atoms may be 48 wt% or more. In general, when the volume ratio of H ₂ /CO increases in the Fischer-Tropsch synthesis reaction, hydrogenation, the main mechanism of chain termination, is promoted, chain growth is not performed well, and selectivity for wax is low. Furthermore, when using the iron-based catalyst with the optimized phase fraction of the present invention, chain growth is promoted even under Fischer-Tropsch reaction conditions with a high hydrogen ratio, thereby increasing the productivity of wax (C ₁₉₊ hydrocarbon).

철계 촉매의 제조방법Method for producing iron-based catalyst

The method for producing an iron-based catalyst according to various embodiments of the present invention may include a first precursor obtaining step, a second precursor slurry forming step, a third precursor manufacturing step, and an activation step.

In the first precursor obtaining step, a mixed solution is prepared by mixing an aqueous salt solution of a metal selected from the group consisting of copper, cobalt, manganese, and combinations thereof and an aqueous iron nitrate solution (Fe(NO ₃ ) ₃ ·9H ₂ O), A precipitate slurry containing the first precursor can be obtained by adding a basic aqueous solution to the mixed solution. When adding a basic aqueous solution to the mixed solution, the process may be carried out at a temperature of 70 to 90° C. for 20 to 80 minutes. Through this, a first precursor having a specific phase fraction can be obtained. Specifically, with respect to 100% of the iron atoms contained in the first precursor, the number of iron atoms contained in ferrihydrite is 70 to 100% and the number of iron atoms contained in goethite is 0 to 30%. A first precursor containing More specifically, the first precursor has a ferrihydrite:goethite phase fraction of 70 to 90%:10 to 30%, or a ferrihydrite phase fraction of 100%, based on the number of iron atoms contained in each phase. You can have

On the other hand, when adding a basic aqueous solution to the mixed solution, if the temperature is less than 70 ℃, there is a problem that each component is not mixed effectively, and if it exceeds 90 ℃, there is a problem that it cannot be mixed at an appropriate concentration due to the evaporation effect of the aqueous solution. .

In addition, if the reaction time by adding the basic aqueous solution to the mixed solution is less than 20 minutes, there is a problem that each component is not mixed effectively, and if it exceeds 80 minutes, the first precursor has a phase fraction of 100% goethite. Therefore, there is a problem that an iron-based catalyst of the phase fraction targeted by the present invention cannot be obtained.

Meanwhile, the basic aqueous solution may specifically be an aqueous solution of sodium carbonate (Na ₂ CO ₃ ), an aqueous solution of sodium hydroxide (NaOH), or aqueous ammonia (NH ₄ OH).

The concentration of the basic aqueous solution is preferably 1 to 5 mol/L, and more preferably 1.5 to 2.5 mol/L. If it is less than 1 mol/L, the amount of aqueous solution used is large, so there is a problem that it takes a lot of time for filtration and washing. If it exceeds 5 mol/L, the pore structure of the precipitate does not develop into a porous structure, which reduces the performance of the catalyst. There is a problem of deterioration.

The pH of the precipitation slurry containing the first precursor is preferably 7 to 9, and more preferably 7.8 to 8.2. If the pH is less than 7 or more than 9, it is difficult to form a precipitated slurry.

After the precipitated slurry containing the first precursor is formed, it can be filtered and washed using distilled water. This is a process to not only improve the performance of the catalyst by removing unnecessary ions such as sodium, carbonate, and nitrate ions, but also to suppress unnecessary reactions during the reaction process.

Washing is preferably performed once or twice in succession. If the washing step is not performed, unnecessary ions such as sodium, carbonate, and nitrate ions exist in the catalyst, which reduces the performance of the catalyst. On the other hand, when performed more than three times, most of the remaining sodium is removed to less than 1 part by weight compared to 100 parts by weight of iron, so not only does sodium not perform its function as a co-catalyst, but the washing step is repeated multiple times, so distilled water is used for this purpose. As the amount increases rapidly and the cleaning time also becomes significantly longer, there is a problem that the economics and efficiency of the overall process are reduced.

Next, in the second precursor slurry forming step, an aqueous solution of at least one oxide of silicon oxide, aluminum oxide, zirconium oxide, or chromium oxide and at least one of an alkali metal or an alkaline earth metal is added to the washed slurry containing the first precursor. It can be added.

The oxide can play a major role in controlling the phase fraction contained in the third precursor, which will be described later, and through this, it is possible to implement a third precursor composed of a combination of iron oxide and iron oxide. Silicon oxide and aluminum oxide can be preferably used as the oxide. Specifically, silicon oxide can be used as fumed silica or colloidal silica.

The alkaline metal may be lithium, sodium, potassium, and rubidium, and the alkaline earth metal may be magnesium, calcium, strontium, and barium. Preferably, it may be an aqueous sodium carbonate solution, an aqueous potassium carbonate solution, an aqueous magnesium carbonate solution, or an aqueous calcium carbonate solution. Meanwhile, instead of adding both the oxide and the aqueous solution, only potassium silicate (Potassium Silicate) may be added.

For example, when manufacturing the second precursor, the additive may be a mixture of potassium carbonate (K ₂ CO ₃ ) aqueous solution and colloidal silica, or potassium carbonate (K ₂ CO ₃ ) aqueous solution and fumed silica (SiO _{2 )} . ) can be used in combination, or potassium silicate can be used alone.

At this time, iron (Fe) contained in the aqueous solution of iron nitrate added in the first precursor obtaining step: Metal contained in the salt aqueous solution of the metal added in the first precursor obtaining step: Alkali metal added in the second precursor slurry forming step, or The mass ratio of the metal contained in the aqueous solution of at least one alkaline earth metal to the oxide added in the second precursor slurry forming step may be 100:4-6:4-7:14-38. If the content of the metal contained in the aqueous salt solution of the metal added in the first precursor obtaining step is less than 4 mass ratio with respect to 100 parts by weight of iron, a problem of increased methane production occurs when producing hydrocarbons, and if it exceeds 6 mass ratio, reaction Problems with reduced activity may occur. If the metal contained in the aqueous solution of at least one of the alkali metals or alkaline earth metals added in the second precursor slurry formation step is less than 4 parts by weight based on 100 parts by weight of iron, it may be difficult to see the effect of suppressing methane production, and if it exceeds 7 parts by weight. In this case, the stability of the catalyst may decrease. In addition, if the oxide added in the second precursor slurry forming step is outside the above range, the degree of improvement in effect is minimal, resulting in uneconomical problems or poor catalytic activity.

Next, in the third precursor manufacturing step, the third precursor can be manufactured by drying and calcining the second precursor slurry. At this time, the second precursor slurry may be dried through spray-drying or rotary evaporation.

In addition, it is preferable to calcinate in a temperature atmosphere of 300 to 500°C. If the temperature is below 300°C, impurities may not be sufficiently vaporized and removed, and the effect of improving the physical strength of the catalyst may be minimal, and if it exceeds 500°C, the catalyst may The pore structure may collapse. The firing time may be 1 to 15 hours, preferably 5 to 12 hours. If the calcination time is less than 1 hour, impurities cannot be sufficiently removed, and if it exceeds 15 hours, economic efficiency may decrease and the pore structure may collapse, resulting in reduced catalytic performance.

Meanwhile, the third precursor may have a specific phase fraction. Specifically, with respect to 100% of the iron atoms contained in the third precursor, 70 to 100% of the iron atoms contained in ferrihydrite and 0 to 30% of the iron atoms contained in hematite. It can be included. More specifically, the third precursor has a ferrihydrite:hematite phase fraction of 70 to 90%:10 to 30% based on the number of iron atoms contained in each phase, or a phase fraction of ferrihydrite of 100%. You can have

Next, in the activation step, the third precursor may be activated by heat treatment in a gas atmosphere containing hydrogen (H ₂ ) and carbon monoxide (CO). By using synthesis gas containing hydrogen and carbon monoxide, the third precursor can be activated, and the phase fraction of iron oxide, iron oxide, and iron carbide contained in the iron-based catalyst can be optimized. Specifically, in the activation step, the third precursor is heat treated under the conditions of a volume ratio of H ₂ /CO of 1 to 3, GHSV of 1 to 12 NL/g _(cat) /h, temperature of 230 to 290 ° C., and pressure of 0.5 to 1.5 MPa. can do.

Meanwhile, when manufacturing the second precursor, activation conditions may vary depending on the type of additive. Specifically, when potassium silicate is used alone as an additive when manufacturing the second precursor, it can be activated at a higher pressure compared to when potassium carbonate (K ₂ CO ₃ ) aqueous solution and colloidal silica are mixed together. For example, when potassium silicate is used alone as an additive when manufacturing the second precursor, activation may proceed under conditions of more than 0.7 MPa and less than 1.5 MPa. Meanwhile, when using a mixture of potassium carbonate (K ₂ CO ₃ ) aqueous solution and colloidal silica, activation is possible even at a low pressure of 0.5 to 0.7 MPa. In other words, if the silica content of the additive is high, it can be activated even at low pressure.

On the other hand, when using a mixture of potassium carbonate (K ₂ CO ₃ ) aqueous solution and fumed silica as an additive when manufacturing the second precursor, H ₂ is higher than when using a mixture of potassium carbonate (K ₂ CO ₃ ) aqueous solution and colloidal silica. It can be activated at a volume ratio of /CO. For example, when using a mixture of potassium carbonate (K ₂ CO ₃ ) aqueous solution and fumed silica, the volume ratio of H ₂ /CO is greater than 1 and less than 3, and GHSV is 4.2 NL/g _(cat) /h or more and 12. Activation may proceed under conditions of NL/g _(cat) /h or less and a pressure of 0.5 to 1.5 MPa.

Through this activation step, the iron-based catalyst with the specific phase fraction described above can be obtained. That is, for 100% of the iron atoms contained in the iron-based catalyst, the number of iron atoms contained in iron oxide is 13 to 80%, the number of iron atoms contained in iron oxide is 1 to 5%, and the number of iron atoms contained in iron carbide is 21. An iron-based catalyst containing from 85% to 85% can be manufactured.

탄화수소의 생산 방법Methods of producing hydrocarbons

The method for producing hydrocarbons according to various embodiments of the present invention can produce liquid hydrocarbons from synthesis gas using the iron-based catalyst described above. The method for producing hydrocarbons of the present invention includes preparing an iron-based catalyst; And it may include producing hydrocarbons by performing a Fischer-Tropsch synthesis reaction using the iron-based catalyst.

Specifically, in the step of preparing the iron-based catalyst, the iron-based catalyst described above can be prepared. That is, it includes iron oxide, iron oxide, and iron carbide, and relative to 100% of the iron atoms contained in the iron-based catalyst, the number of iron atoms contained in iron oxide is 13 to 80%, and the number of iron atoms contained in iron oxide is 1 to 80%. An iron-based catalyst containing 5% and 21 to 85% of iron atoms contained in iron carbide can be prepared. At this time, the iron-based catalyst is an iron-based catalyst activated under the conditions of a H ₂ /CO volume ratio of 1 to 3, GHSV of 1 to 12 NL/g _(cat) /h, temperature of 230 to 290 ° C., and pressure of 0.5 to 1.5 MPa.

In the step of producing hydrocarbons, the Fischer-Tropsch synthesis reaction can be performed using the iron-based catalyst. At this time, the Fischer-Tropsch synthesis reaction will be carried out under reaction conditions of a volume ratio of H ₂ /CO of 1 to 5, GHSV of 1 to 13 NL/g _(cat) /h, temperature of 230 to 290 ℃, and pressure of 1.5 to 2.0 MPa. You can.

Through the method for producing hydrocarbons of the present invention, more than 80 wt% of C ₅₊ hydrocarbons and more than 48 wt% of wax can be produced.

Hereinafter, the present invention will be described in detail through specific examples.

However, the following examples are only for illustrating the present invention and the present invention is not limited by the following examples.

실시예Example

Example 1

A mixed solution was prepared by mixing a 2 molar concentration of iron nitrate (Fe(NO ₃ ) ₃ 9H ₂ O) aqueous solution and copper nitrate (Cu(NO ₃ ) ₂ 5H ₂ O) aqueous solution, and the mixed solution was heated to a temperature of about 80°C. A 2 molar aqueous solution of sodium carbonate (Na ₂ CO ₃ ) was added so that the pH reached 8 for about 80 minutes, and ferrihydrite (FeOOH· n H ₂ O, 0) was calculated based on the number of iron atoms contained in each phase in the solid precipitate. < n <1): goethite (FeOOH) = 80%: A first precursor consisting of a phase fraction of 20% was obtained. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and fumed silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and fumed silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:20. After drying the second precursor slurry through spray-drying, it was calcined in an air atmosphere at 400 °C for 8 hours to produce ferrihydrite: hematite (a-Fe ₂ O) based on the number of iron atoms contained in each phase. ₃ ) = 80%: A third precursor consisting of a phase fraction of 20% was obtained. The third precursor was heated at a temperature of 275 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 2: 1 at 4.2 NL/g _(cat) /h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 2

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 1. The third precursor was heated at a temperature of 275 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 3: 1 at 5.6 NL/g _(cat) /h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 3

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:20. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 1 using the third precursor.

Example 4

A mixed solution was prepared by mixing a 2 molar concentration of iron nitrate (Fe(NO ₃ ) ₃ 9H ₂ O) aqueous solution and copper nitrate (Cu(NO ₃ ) ₂ 5H ₂ O) aqueous solution, and the mixed solution was heated to a temperature of about 80°C. A 2 molar aqueous solution of sodium carbonate (Na ₂ CO ₃ ) was added so that the pH reached 8 for about 20 minutes to obtain a first precursor containing only ferrihydrite as an iron-based compound. A second precursor slurry was prepared in the same manner as in Example 3 using the first precursor. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:20. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to obtain a third precursor containing only ferrihydrite as an iron-based compound. An activated catalyst was prepared in the same manner as Example 1 using the third precursor.

Example 5

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and potassium silicate with a mass ratio of K:SiO ₂ = 5:20 was added to the washed precipitated slurry. A second precursor slurry was prepared by adding an aqueous solution. The amount of copper nitrate and potassium silicate aqueous solution used was adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:20. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 1 using the third precursor.

Example 6

The first precursor was prepared in the same manner as in Example 4. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica and potassium carbonate (K ₂ CO ₃ ) aqueous solution were added to the washed precipitate slurry to produce the second precipitate slurry. A precursor slurry was prepared. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:16. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to obtain a third precursor containing only ferrihydrite as an iron-based compound. An activated catalyst was prepared in the same manner as Example 1 using the third precursor.

Example 7

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 6. The third precursor was heated at a temperature of 275 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 2: 1 at 4.2 NL/g _(cat) /h at a pressure of 0.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 8

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 6. The third precursor contains H ₂ and CO, and a gas with a volume ratio of H ₂ : CO = 2: 1 was flowed at 4.2 NL/g _(cat) / h at a pressure of 1.0 MPa and a temperature of 275 ° C for 20 hours. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 9

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 5. The third precursor was heated at a temperature of 255 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 2: 1 at 2.8 NL/g _(cat) /h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 10

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 1. The third precursor was heated at a temperature of 290 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 3: 1 at 11.2 NL/g _(cat) /h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 11

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 5. The third precursor was heated at a temperature of 230 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 2: 1 at 1.0 NL/g _(cat) /h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 12

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:26. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. The third precursor was heated at a temperature of 275 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 1: 1 at 2.8 NL/g _(cat) /h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 13

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:28. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 12 using the third precursor.

Example 14

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:30. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 12 using the third precursor.

Example 15

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:32. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 12 using the third precursor.

Example 16

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:34. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 12 using the third precursor.

Example 17

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:36. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 12 using the third precursor.

Example 18

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:38. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 12 using the third precursor.

Example 19

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 15. The third precursor was heated at a temperature of 275 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 2: 1 at 2.25 NL/g _(cat) / h at a pressure of 0.7 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 20

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:6:32. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 19 using the third precursor.

Example 21

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 20. An activated catalyst was prepared in the same manner as Example 12 using the third precursor.

Example 22

The first precursor was prepared in the same manner as Example 1. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica (SiO ₂ ) and potassium carbonate (K ₂ CO _{3 )} were added to the washed precipitated slurry. ) A second precursor slurry was prepared by adding an aqueous solution. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:7:32. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to produce a phase fraction of ferrihydrite:hematite = 80%: 20% based on the number of iron atoms contained in each phase. A third precursor was obtained. An activated catalyst was prepared in the same manner as Example 12 using the third precursor.

Example 23

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 15. The third precursor was heated at a temperature of 260 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 1: 1 at 1.4 NL/g _(cat) /h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Example 24

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 20. An activated catalyst was prepared in the same manner as Example 23 using the third precursor.

Comparative Example 1

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 1. The third precursor was heat treated at a temperature of 280 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 1: 1 at 2.8 NL/g _(cat) / h at normal pressure. An activated iron-based catalyst was obtained.

Comparative Example 2

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 1. The third precursor was heated at a temperature of 280 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 1: 1 at 2.8 NL/g _(cat) /h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Comparative Example 3

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 1. The third precursor was heated at a temperature of 305 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 3: 1 at 15.4 NL/g _(cat) / h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Comparative Example 4

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 1. The third precursor was heated at a temperature of 320 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 3: 1 at 19.6 NL/g _(cat) / h at a pressure of 1.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Comparative Example 5

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 3. The third precursor was heat treated at a temperature of 280 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 2: 1 at 4.2 NL/g _(cat) / h at normal pressure. An activated iron-based catalyst was obtained.

Comparative Example 6

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 6. The third precursor was heat treated at a temperature of 275 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 2: 1 at 4.2 NL/g _(cat) / h at normal pressure. An activated iron-based catalyst was obtained.

Comparative Example 7

A mixed solution was prepared by mixing a 2 molar aqueous solution of iron nitrate and an aqueous copper nitrate solution, and a 2 molar aqueous solution of sodium carbonate was added to the mixed solution to reach pH 8 at a temperature of about 80°C for about 20 hours to produce goethite. A first precursor containing only iron-based compounds was obtained. The precipitated slurry containing the first precursor was filtered and washed using distilled water to sufficiently remove residual sodium, and colloidal silica and potassium carbonate (K ₂ CO ₃ ) aqueous solution were added to the washed precipitate slurry to produce the second precipitate slurry. A precursor slurry was prepared. The amounts of copper nitrate, potassium carbonate, and colloidal silica used were adjusted to a mass ratio of Fe:Cu:K:SiO ₂ = 100:5:5:16. After drying the second precursor slurry through a spray drying method, it was calcined in an air atmosphere at 400 °C for 8 hours to obtain a third precursor containing only hematite as an iron-based compound. The third precursor was heated at a temperature of 275 °C for 20 hours while flowing a gas containing H ₂ and CO and having a volume ratio of H ₂ : CO = 2: 1 at 4.2 NL/g _(cat) /h at a pressure of 0.5 MPa. Heat treatment was performed to obtain an activated iron-based catalyst.

Comparative Example 8

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Comparative Example 8. The third precursor contains H ₂ and CO, and a gas with a volume ratio of H ₂ : CO = 2: 1 was flowed at 4.2 NL/g _(cat) / h at a pressure of 1.0 MPa and a temperature of 275 ° C for 20 hours. Heat treatment was performed to obtain an activated iron-based catalyst.

Comparative Example 9

The first precursor, second precursor slurry, and third precursor were prepared in the same manner as in Example 5. An activated catalyst was prepared in the same manner as Example 19 using the third precursor.

Meanwhile, the process conditions according to Examples 1 to 9 and Comparative Examples 1 to 9 can be compared as shown in Table 1 below.

	반응 시간reaction hour	제1 전구체 상분율First precursor phase fraction	제2 전구체 제조 시 첨가물 second precursor Additives in manufacturing		제3 전구체 상분율Third precursor phase fraction	활성화 조건Activation conditions
	반응 시간reaction hour	제1 전구체 상분율First precursor phase fraction	제2 전구체 제조 시 첨가물 second precursor Additives in manufacturing		제3 전구체 상분율Third precursor phase fraction	H₂/CO _H2 /CO	공간속도 (NL/g_(cat)/h)space speed (NL/g _(cat) /h)	T (°C)T (°C)	P (MPa)P (MPa)
실시예 1Example 1	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Fumed silicafumed silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	4.2 4.2	275 275	1.5 1.5
실시예 2Example 2	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Fumed silicafumed silica	Fumed silicafumed silica	33	5.65.6	275 275	1.5 1.5
실시예 3Example 3	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	4.2 4.2	275 275	1.5 1.5
실시예 4Example 4	20 분20 minutes		Ferrihydrite 100%Ferrihydrite 100%	K₂CO₃ K ₂ CO ₃	Colloidal silica Colloidal silica		Ferrihydrite 100%Ferrihydrite 100%	22	4.2 4.2	275 275	1.5 1.5
실시예 5Example 5	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	규산칼륨potassium silicate		ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	4.2 4.2	275 275	1.5 1.5
실시예 6Example 6	20 분20 minutes		Ferrihydrite 100%Ferrihydrite 100%	K₂CO₃ K ₂ CO ₃	Colloidal silica Colloidal silica	Ferrihydrite 100%Ferrihydrite 100%	22	4.2 4.2	275 275	1.5 1.5
실시예 7Example 7	20 분20 minutes	Ferrihydrite 100%Ferrihydrite 100%	K₂CO₃ K ₂ CO ₃	Colloidal silica Colloidal silica	Ferrihydrite 100%Ferrihydrite 100%	22	4.2 4.2	275 275	0.50.5
실시예 8Example 8	20 분20 minutes	Ferrihydrite 100%Ferrihydrite 100%	K₂CO₃ K ₂ CO ₃	Colloidal silica Colloidal silica	Ferrihydrite 100%Ferrihydrite 100%	22	4.2 4.2	275 275	1.01.0
실시예 9Example 9	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	규산칼륨potassium silicate		ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	2.82.8	255255	1.51.5
실시예 10Example 10	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Fumed silicafumed silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	33	11.211.2	290290	1.51.5
실시예 11Example 11	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	규산칼륨potassium silicate		ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	1.01.0	230230	1.51.5
실시예 12Example 12	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 13Example 13	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 14Example 14	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 15Example 15	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 16Example 16	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 17Example 17	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 18Example 18	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 19Example 19	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	2.252.25	275275	0.70.7
실시예 20Example 20	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	2.252.25	275275	0.70.7
실시예 21Example 21	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 22Example 22	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	275275	1.51.5
실시예 23Example 23	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	1.41.4	260260	1.51.5
실시예 24Example 24	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	1.41.4	260260	1.51.5
비교예 1Comparative Example 1	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Fumed silicafumed silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	280280	상압normal pressure
비교예 2Comparative Example 2	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Fumed silicafumed silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	1One	2.82.8	280280	1.51.5
비교예 3Comparative Example 3	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Fumed silicafumed silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	33	15.415.4	305305	1.51.5
비교예 4Comparative Example 4	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Fumed silicafumed silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	33	19.619.6	320320	1.51.5
비교예 5Comparative Example 5	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	4.24.2	280280	상압normal pressure
비교예 6Comparative Example 6	20 분20 minutes	Ferrihydrite 100%Ferrihydrite 100%	K₂CO₃ K ₂ CO ₃	Colloidal silica Colloidal silica	Ferrihydrite 100%Ferrihydrite 100%	22	4.24.2	275275	상압normal pressure
비교예 7Comparative Example 7	20 시간20 hours	Goethite 100 %Goethite 100%	K₂CO₃ K ₂ CO ₃	Colloidal silicaColloidal silica	Hematite 100 %Hematite 100%	22	4.24.2	275275	0.50.5
비교예 8Comparative Example 8	20 시간20 hours	Goethite 100 %Goethite 100%	K₂CO₃ K ₂ CO ₃	Colloidal silica Colloidal silica	Hematite 100 %Hematite 100%	22	4.24.2	275275	1.01.0
비교예9Comparative Example 9	80 분80 minutes	ferrihydrite : goethite = 80% : 20%ferrihydrite : goethite = 80% : 20%	규산칼륨potassium silicate		ferrihydrite : hematite = 80% : 20%ferrihydrite : hematite = 80% : 20%	22	2.252.25	275275	0.70.7

*Reaction time: Time for reaction by adding basic aqueous solution to the mixed solution. The phase fraction of the activated iron-based catalyst prepared by the method of Examples 1, 2, 12, 15 and Comparative Example 2 was analyzed by Mössbauer spectroscopy. They are shown in Figures 1, 2, 3, 4, and 5, respectively, and the phase fractions were calculated from the Mössbauer spectroscopy results of Figures 1 to 5 and listed in Table 2 below. The unit of phase fraction of each phase is Fe-mol%.

	FeOOH·nH₂OFeOOH· nH ₂ O	Fe₃O₄ Fe ₃ O ₄	c-Fe₅C₂ c-Fe ₅ C ₂	e`-Fe_2.2Ce`-Fe _2.2 C
실시예 1Example 1	24.724.7	2.852.85	63.063.0	9.439.43
실시예 2Example 2	16.116.1	2.362.36	71.471.4	10.110.1
실시예 12Example 12	54.754.7	--	45.345.3	--
실시예 15Example 15	77.277.2	--	22.922.9	--
비교예 2Comparative Example 2	12.812.8	22.422.4	59.959.9	4.874.87

The activated iron-based catalysts prepared by the methods of Examples 1 to 24 and Comparative Examples 1 to 9 were placed in a laboratory-grade fixed bed reactor (catalyst usage: 0.1 to 1.0 g), and their performance was evaluated under the FTS reaction conditions shown in Table 3 below. The results are shown in Table 3 below.

	FTS 반응조건FTS reaction conditions				촉매성능Catalytic performance
	H₂/CO _H2 /CO	공간속도 (NL/g_(cat)/h)space speed (NL/g _(cat) /h)	온도 (℃)temperature (℃)	압력 (MPa)enter (MPa)	CO 전환율 (%)C.O. conversion rate (%)	CO₂ 선택도 (%) _CO2 selectivity (%)	탄화수소 분포 (wt%)Hydrocarbon distribution (wt%)
	H₂/CO _H2 /CO	공간속도 (NL/g_(cat)/h)space speed (NL/g _(cat) /h)	온도 (℃)temperature (℃)	압력 (MPa)enter (MPa)	CO 전환율 (%)C.O. conversion rate (%)	CO₂ 선택도 (%) _CO2 selectivity (%)	CH₄ CH ₄	C₂-C₄ C ₂ -C ₄	C₅₊ C ₅₊	C₁₉₊ C ₁₉₊
실시예 1Example 1	22	4.24.2	275275	1.51.5	63.563.5	36.836.8	2.162.16	5.505.50	92.392.3	72.272.2
실시예 2Example 2	33	5.65.6	275275	1.51.5	72.472.4	33.633.6	2.552.55	4.354.35	93.193.1	69.169.1
실시예 3Example 3	22	4.24.2	275275	1.51.5	67.967.9	38.938.9	2.562.56	6.236.23	91.291.2	68.168.1
실시예 4Example 4	22	4.24.2	275275	1.51.5	65.265.2	37.637.6	3.333.33	8.698.69	88.088.0	62.262.2
실시예 5Example 5	22	4.24.2	275275	1.51.5	74.574.5	40.740.7	2.612.61	5.785.78	91.691.6	68.768.7
실시예 6Example 6	22	4.24.2	275275	1.51.5	71.271.2	40.340.3	3.873.87	9.019.01	87.187.1	62.762.7
실시예 7Example 7	22	4.24.2	275275	1.51.5	74.474.4	40.540.5	4.784.78	10.310.3	84.984.9	60.260.2
실시예 8Example 8	22	4.24.2	275275	1.51.5	70.670.6	40.540.5	4.504.50	9.839.83	85.785.7	62.662.6
실시예 9Example 9	22	2.82.8	255255	1.51.5	70.470.4	39.639.6	2.652.65	5.645.64	91.791.7	71.071.0
실시예 10Example 10	33	11.211.2	290290	1.51.5	50.550.5	33.733.7	7.137.13	11.111.1	81.781.7	51.551.5
실시예 11Example 11	22	1.01.0	230230	1.51.5	67.067.0	36.436.4	2.442.44	8.948.94	88.6 88.6	77.7 77.7
실시예 12Example 12	1One	2.82.8	275275	1.51.5	49.249.2	32.232.2	4.03 4.03	11.6 11.6	84.4 84.4	48.2 48.2
실시예 13Example 13	1One	2.82.8	275275	1.51.5	46.546.5	30.930.9	3.89 3.89	10.3 10.3	85.8 85.8	49.8 49.8
실시예 14Example 14	1One	2.82.8	275275	1.51.5	44.044.0	30.530.5	3.49 3.49	9.35 9.35	87.2 87.2	51.4 51.4
실시예 15Example 15	1One	2.82.8	275275	1.51.5	33.433.4	27.227.2	2.97 2.97	7.65 7.65	88.2 88.2	56.7 56.7
실시예 16Example 16	1One	2.82.8	275275	1.51.5	38.938.9	28.928.9	3.14 3.14	7.76 7.76	89.1 89.1	55.0 55.0
실시예 17Example 17	1One	2.82.8	275275	1.51.5	25.825.8	26.526.5	3.21 3.21	7.93 7.93	88.8 88.8	60.4 60.4
실시예 18Example 18	1One	2.82.8	275275	1.51.5	24.824.8	20.420.4	3.69 3.69	7.31 7.31	89.0 89.0	59.9 59.9
실시예 19Example 19	22	2.252.25	275275	0.70.7	52.452.4	33.333.3	4.16 4.16	7.72 7.72	88.1 88.1	58.0 58.0
실시예 20Example 20	22	2.252.25	275275	0.70.7	55.155.1	34.034.0	3.09 3.09	6.14 6.14	90.8 90.8	59.7 59.7
실시예 21Example 21	1One	2.82.8	275275	1.51.5	40.640.6	31.031.0	3.31 3.31	8.52 8.52	88.2 88.2	55.8 55.8
실시예 22Example 22	1One	2.82.8	275275	1.51.5	49.149.1	36.136.1	3.72 3.72	11.1 11.1	85.2 85.2	51.7 51.7
실시예 23Example 23	1One	1.41.4	260260	1.51.5	25.225.2	23.023.0	2.78 2.78	7.22 7.22	90.0 90.0	65.0 65.0
실시예 24Example 24	1One	1.41.4	260260	1.51.5	31.531.5	27.027.0	2.61 2.61	7.71 7.71	89.7 89.7	69.3 69.3
비교예 1Comparative Example 1	1One	2.82.8	275275	1.51.5	86.786.7	43.743.7	10.6 10.6	26.9 26.9	62.5 62.5	19.4 19.4
비교예 1Comparative Example 1	1One	2.82.8	230230	1.51.5	33.833.8	36.236.2	6.54 6.54	17.8 17.8	75.7 75.7	41.2 41.2
비교예 1Comparative Example 1	1One	2.82.8	245245	1.51.5	56.656.6	39.639.6	5.41 5.41	18.5 18.5	76.1 76.1	39.9 39.9
비교예 1Comparative Example 1	1One	2.82.8	260260	1.51.5	69.869.8	42.342.3	6.87 6.87	21.9 21.9	71.2 71.2	30.7 30.7
비교예 1Comparative Example 1	1One	2.82.8	290290	1.51.5	88.988.9	44.344.3	15.5 15.5	33.1 33.1	51.4 51.4	9.65 9.65
비교예 2Comparative Example 2	1One	2.82.8	275275	1.51.5	64.164.1	41.241.2	6.03 6.03	14.4 14.4	79.6 79.6	43.1 43.1
비교예 3Comparative Example 3	33	15.415.4	305305	1.51.5	52.652.6	36.236.2	22.1 22.1	33.8 33.8	44.0 44.0	11.5 11.5
비교예 4Comparative Example 4	33	19.619.6	320320	1.51.5	65.665.6	37.337.3	22.4 22.4	28.7 28.7	48.9 48.9	7.46 7.46
비교예 5Comparative Example 5	22	4.24.2	275275	1.51.5	78.978.9	37.737.7	10.9 10.9	21.6 21.6	67.5 67.5	34.7 34.7
비교예 6Comparative Example 6	22	4.24.2	275275	1.51.5	68.868.8	37.337.3	12.7 12.7	28.3 28.3	59.0 59.0	25.4 25.4
비교예 7Comparative Example 7	22	4.24.2	275275	1.51.5	56.956.9	38.038.0	11.2 11.2	24.4 24.4	64.4 64.4	29.3 29.3
비교예 8Comparative Example 8	22	4.24.2	275275	1.51.5	40.540.5	36.536.5	8.94 8.94	21.0 21.0	70.1 70.1	38.1 38.1
비교예 9Comparative Example 9	22	2.252.25	275275	0.70.7	63.163.1	44.144.1	7.16 7.16	17.8 17.8	72.4 72.4	49.4 49.4

Referring to Table 3, the activated iron-based catalyst prepared by the method of Examples 1 to 24 is selected for C ₅₊ hydrocarbon and wax (C ₁₉₊ hydrocarbon), which are the target products in the low-temperature Fischer-Tropsch synthesis reaction. It can be seen that the degree is significantly higher than that of the activated iron-based catalyst prepared by the method of Comparative Examples 1 to 9. Referring to Table 3, the activated iron-based catalyst prepared by the method of Examples 12 to 18, 23 and 24 has a selectivity for CO ₂ , an unnecessary by-product in the Fischer-Tropsch synthesis reaction, by the method of Comparative Examples 1 to 9. It can be confirmed that it is significantly lower than the activated iron-based catalyst prepared.

Referring to Table 3, the activated iron-based catalyst prepared by the method of Examples 19 and 20 produces C ₅₊ hydrocarbons and wax (C ₁₉₊ hydrocarbons) even when Fischer-Tropsch synthesis reaction is performed under low pressure conditions of 0.7 MPa. It can be seen that the selectivity for is significantly higher than when the Fischer-Tropsch synthesis reaction was performed under a pressure condition of 1.5 MPa using the activated iron-based catalyst prepared by the method of Comparative Examples 1 to 8.

Meanwhile, for the activated iron-based catalyst prepared by the method of Example 9, H ₂ : CO = 2: 1, space velocity = 2.8 NL/g _(cat) /h, temperature = 255 °C, pressure = 1.5 MPa, Fisher -The results of long-term performance evaluation under Tropsch synthesis reaction conditions are shown in Figure 6. Referring to Figure 6, it can be seen that the activated iron-based catalyst prepared by the method of Example 9 maintains excellent activity for about 1,000 hours.

The features, structures, effects, etc. described in the above-described embodiments are included in at least one embodiment of the present invention and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects, etc. illustrated in each embodiment can be combined or modified and implemented in other embodiments by a person with ordinary knowledge in the field to which the embodiments belong. Therefore, contents related to such combinations and modifications should be construed as being included in the scope of the present invention.

In addition, although the description has been made focusing on the embodiments above, this is only an example and does not limit the present invention, and those skilled in the art will understand the above examples without departing from the essential characteristics of the present embodiments. You will be able to see that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. And these variations and differences in application should be construed as being included in the scope of the present invention as defined in the attached claims.

The present invention suppresses the production of CO ₂ , CH ₄ and C ₂ -C ₄ hydrocarbons, which are unnecessary by-products in the Fischer-Tropsch synthesis reaction, and significantly increases the productivity of (C ₅₊ ) hydrocarbons with a carbon number of 5 or more, thereby providing industrial benefits. High availability.

Claims

As an iron-based catalyst,

Contains iron oxide, iron oxide and iron carbide,

With respect to 100% of the number of iron atoms contained in the iron-based catalyst, the number of iron atoms contained in the iron oxide is 13 to 80%, the number of iron atoms contained in the iron oxide is 1 to 5%, and the number of iron atoms contained in the iron carbide is 100%. An iron-based catalyst containing 21 to 85% of water.
According to paragraph 1,

The iron-based catalyst in which the iron oxide is ferrihydrite.
According to paragraph 1,

The iron oxide is an iron-based catalyst called magnetite.
According to paragraph 1,

The iron carbide is at least one iron-based catalyst selected from the group consisting of c-carbide (Fe 5 C 2 ) and ε'-carbide (Fe 2.2 C).
According to paragraph 1,

The iron carbide includes c-carbide (Fe 5 C 2 ) and ε'-carbide (Fe 2.2 C),

With respect to 100% of the iron atoms contained in the iron-based catalyst, the number of iron atoms contained in c-carbide (Fe 5 C 2 ) is 21 to 75% and the number of iron atoms contained in the ε'-carbide (Fe 2.2 C) iron-based catalyst containing 6 to 13%.
According to paragraph 1,

The iron-based catalyst has a carbon number of 5 under the Fischer-Tropsch reaction conditions of a H 2 /CO volume ratio of 1 to 5, a GHSV of 1 to 13 NL/g (cat) /h, a temperature of 230 to 290 ° C., and a pressure of 0.5 to 2.0 MPa. An iron-based catalyst characterized in that the selectivity for hydrocarbons (C 5+ ) is 80 wt% or more.
A mixed solution is prepared by mixing an aqueous salt solution of a metal selected from the group consisting of copper, cobalt, manganese, and combinations thereof with an aqueous iron nitrate solution, and adding a basic aqueous solution to the mixed solution to obtain a first precursor. step;

A second precursor slurry forming step of forming a second precursor slurry by adding at least one oxide of silicon oxide, aluminum oxide, zirconium oxide, or chromium oxide and an aqueous solution of at least one of an alkali metal or an alkaline earth metal to the first precursor;

A third precursor production step of drying and calcining the second precursor slurry to produce a third precursor; and

An activation step of activating the third precursor by heat treatment,

The activation step is,

An iron-based method, characterized in that the third precursor is heat-treated under the conditions of a volume ratio of H 2 /CO of 1 to 3, GHSV of 1 to 12 NL/g (cat) /h, temperature of 230 to 290 ℃, and pressure of 0.5 to 1.5 MPa. Method for producing catalyst.
In clause 7,

In the step of obtaining the first precursor, the reaction time for adding a basic aqueous solution to the mixed solution is 20 to 80 minutes.
In clause 7,

Comprising 70 to 100% of iron atoms contained in ferrihydrite and 0 to 30% of iron atoms contained in goethite, relative to 100% of the number of iron atoms contained in the first precursor. Method for producing iron-based catalyst.
In clause 7,

Comprising 70 to 100% of the iron atoms contained in ferrihydrite and 0 to 30% of the iron atoms contained in hematite, relative to 100% of the iron atoms contained in the third precursor. Method for producing iron-based catalyst.
Preparing an iron-based catalyst; and

Producing hydrocarbons by performing a Fischer-Tropsch synthesis reaction using the iron-based catalyst,

The iron-based catalyst is,

Contains iron oxide, iron oxide and iron carbide,

With respect to 100% of the number of iron atoms contained in the iron-based catalyst, the number of iron atoms contained in the iron oxide is 13 to 80%, the number of iron atoms contained in the iron oxide is 1 to 5%, and the number of iron atoms contained in the iron carbide is 100%. A method for producing hydrocarbons, characterized in that it contains 21 to 85% of water.
According to clause 11,

The iron oxide is ferrihydrite,

The iron oxide is magnetite,

The iron carbide includes c-carbide (Fe 5 C 2 ) and ε'-carbide (Fe 2.2 C),

With respect to 100% of the iron atoms contained in the iron-based catalyst, the number of iron atoms contained in c-carbide (Fe 5 C 2 ) is 21 to 75% and the number of iron atoms contained in the ε'-carbide (Fe 2.2 C) is 6. to 13%.
According to clause 11,

The iron-based catalyst is,

A method for producing hydrocarbons, characterized in that it is activated under the conditions of a volume ratio of H 2 /CO of 1 to 3, GHSV of 1 to 12 NL/g (cat) /h, temperature of 230 to 290 ℃, and pressure of 0.5 to 1.5 MPa.
According to clause 11,

The Fischer-Tropsch synthesis reaction is,

A method for producing hydrocarbons, characterized in that the reaction is carried out under reaction conditions of a volume ratio of H 2 /CO of 1 to 5, GHSV of 1 to 13 NL/g (cat) /h, temperature of 230 to 290 ℃, and pressure of 0.5 to 2.0 MPa.
According to clause 11,

The hydrocarbons are,

A method for producing hydrocarbons, characterized in that hydrocarbons with a carbon number of 5 or more (C 5+ ) are 80 wt% or more.