Catalyst for converting carbon dioxide to methanol and method for preparing methanol
A catalyst with copper, zinc, aluminum, and indium or cerium oxides enhances carbon dioxide conversion to methanol, addressing inefficiencies in existing methods by improving conversion rates and selectivity.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- CPC CORPORATION
- Filing Date
- 2025-02-13
- Publication Date
- 2026-07-01
AI Technical Summary
Current industrial methods for converting carbon dioxide into methanol are inefficient, with low conversion rates and selectivity, limited by thermodynamic constraints and poor catalyst performance.
A catalyst comprising copper, zinc, aluminum, and a first modifier selected from indium or cerium oxides, optionally with a second modifier such as gallium or zirconium oxides, is used in a hydrogenation reaction to enhance carbon dioxide conversion to methanol.
The catalyst significantly improves carbon dioxide conversion rates, methanol selectivity, and production rates, outperforming conventional catalysts by enhancing activity and efficiency.
Smart Images
Figure 2026109478000001
Abstract
Description
Technical Field
[0001] The present invention relates to a catalyst for converting carbon dioxide into methanol, and particularly to a catalyst for converting carbon dioxide into methanol, which contains a first modifier, and the first modifier is selected from the group consisting of indium (In) or its oxide and cerium (Ce) or its oxide. The present invention also provides a method for preparing methanol.
Background Art
[0002] Carbon dioxide is one of the gases that cause the greenhouse effect. The reduction of carbon dioxide can be addressed from both reducing emissions and decreasing the concentration in the environment. Regarding the reduction of emissions, efforts can be made through improving energy efficiency and energy conservation, and the development of energy utilization that does not emit carbon dioxide is the main research goal. The reduction of the concentration in the environment can be achieved by recovering and storing carbon dioxide, and then carbon dioxide is converted into chemical substances and fuels. This can not only reduce carbon dioxide emissions, but also suppress the dependence on petrochemical raw materials, and further enhance the economic effect.
[0003] Methanol has a wide range of uses. For example, it can be directly used as a liquid fuel for methanol fuel cells for internal combustion engines, or industrial raw materials such as formaldehyde, ethylene, propylene, and acetic acid can be produced as chemical precursor raw materials. However, currently, the industrial method for converting carbon dioxide into methanol is not effective, and the production rate of methanol cannot be improved due to thermodynamic limitations. Under general methanol production conditions, the conversion rate of carbon dioxide remains at about 17%, and the selectivity of methanol is less than 80% (equivalent to a production rate of less than 13.6%), indicating that the performance of the catalyst used is not good and the efficiency in the process is insufficient.
[0004] Therefore, currently, in order to improve the activity and efficiency of converting carbon dioxide into methanol, it is necessary to develop a process technology for converting carbon dioxide into methanol and related catalysts. [Overview of the project] [Problems that the invention aims to solve]
[0005] Conventional catalysts for converting carbon dioxide to methanol still have room for improvement. Therefore, the object of the present invention is to provide a novel catalyst for converting carbon dioxide to methanol and a method for preparing methanol in order to improve the activity and efficiency of the conversion of carbon dioxide to methanol. [Means for solving the problem]
[0006] To achieve the above-mentioned objectives and other objectives, the catalyst for converting carbon dioxide to methanol provided by the present invention is: 30 to 70 parts by weight of copper (Cu) or its oxide, 20 to 50 parts by weight of zinc (Zn) or its oxide, 2 to 10 parts by weight of aluminum (Al) or its oxide, The solution comprises 0.1 to 10 parts by weight of a first modifier, the first modifier being selected from the group consisting of indium (In) or its oxides and cerium (Ce) or its oxides.
[0007] In one embodiment of the present invention, the first modifier is indium (In) or its oxide, and the content of indium (In) or its oxide may be 0.05 wt% to 5 wt% based on the total weight of copper (Cu) or its oxide, zinc (Zn) or its oxide, aluminum (Al) or its oxide, and the first modifier.
[0008] In one embodiment of the present invention, the first modifier is cerium (Ce) or its oxide, and the content of cerium (Ce) or its oxide may be 0.05 wt% to 5 wt% based on the total weight of copper (Cu) or its oxide, zinc (Zn) or its oxide, aluminum (Al) or its oxide, and the first modifier.
[0009] In one embodiment of the present invention, the first modifier is composed of indium (In) or its oxide and cerium (Ce) or its oxide, and the content of indium (In) or its oxide and cerium (Ce) or its oxide may be independently 0.05 wt% to 5 wt% based on the total weight of copper (Cu) or its oxide, zinc (Zn) or its oxide, aluminum (Al) or its oxide, and the first modifier.
[0010] In one embodiment of the present invention, the catalyst for converting carbon dioxide to methanol may further include a second modifier selected from the group consisting of gallium (Ga) or its oxides and zirconium (Zr) or its oxides.
[0011] To achieve the above-mentioned objectives and other objectives, the methanol preparation method provided by the present invention is: A step of introducing a catalyst for converting the carbon dioxide into methanol into a fixed-bed reactor, A step of introducing hydrogen (H2) and carbon dioxide gas into the fixed-bed reactor, carrying out a hydrogenation reaction under the action of a catalyst for converting the carbon dioxide to methanol, and producing methanol, Includes.
[0012] In one embodiment of the present invention, the space velocity (gas hourly space velocity; GHSV) of the hydrogenation reaction is 3000 to 20000 h -1 It is between these two points.
[0013] In one embodiment of the present invention, the temperature of the hydrogenation reaction is between 200 and 300°C.
[0014] In one embodiment of the present invention, the pressure of the hydrogenation reaction is 30-80 kg / cm². 2 It is between these two points. [Effects of the Invention]
[0015] The catalyst for converting carbon dioxide to methanol according to the present invention can effectively improve the activity and efficiency of converting carbon dioxide to methanol by adding a first modifier. The method for preparing methanol according to the present invention can effectively improve the production rate of methanol by using the catalyst for converting carbon dioxide to methanol.
Embodiments for Carrying Out the Invention
[0016] In order to fully understand the object, features, and effects of the present invention, specific examples will be given below and the present invention will be described in detail.
[0017] Preparation of materials:
[0018] Liquid A: Dissolve 54.3 g of Cu(NO3)2, 39.1 g of Zn(NO3)2, and 6.6 g of Al(NO3)3 in 1500 mL of deionized water.
[0019] Liquid A’: Dissolve 54.3 g of Cu(NO3)2, 39. g of Zn(NO3)2, 6.6 g of Al(NO3)3, 12 g of Zr(NO3)4, and 10 g of Ga(NO3)2 in 1500 mL of deionized water.
[0020] Liquid B: Dissolve 140 g of Na2CO3 in 500 mL of deionized water.
[0021] Liquid C: Prepare by putting 400 g of deionized water in a beaker.
[0022] 〔Example 1〕: Cu-Zn-Al-In (Catalyst I)
[0023] Liquid A and liquid B are added to stirred liquid C at a rate of 10 mL / min, stirred for 24 hours, then filtered to obtain a filter cake. Thereafter, the filter cake is washed several times with deionized water to remove sodium ions, dried at 110 °C, and then calcined at 600 °C to produce catalyst precursor I. After waiting until it reaches room temperature, 10 g of catalyst precursor I is placed in a pear-shaped flask, 0.026 g of In(NO3)3 solution is added, extracted and dried with a rotary evaporator, dried at 110 °C, and then calcined at 600 °C to produce catalyst I.
[0024] The catalyst I of Example 1 includes a first modifier composed of indium (In) or its oxide by adding 0.026 g of In(NO3)3 solution during the process.
[0025] 〔Example 2〕: Cu-Zn-Al-Ce (Catalyst II)
[0026] Liquid A and liquid B are added to stirred liquid C at a rate of 10 mL / min, stirred for 24 hours, then filtered to obtain a filter cake. Thereafter, the filter cake is washed several times with deionized water to remove sodium ions, dried at 110 °C, and then calcined at 600 °C to produce catalyst precursor I. After waiting until it reaches room temperature, 10 g of catalyst precursor I is placed in a pear-shaped flask, 0.031 g of Ce(NO3)3 solution is added, extracted and dried with a rotary evaporator, dried at 110 °C, and then calcined at 600 °C to produce catalyst II.
[0027] The catalyst II of Example 2 includes a first modifier composed of cerium (Ce) or its oxide by adding 0.031 g of Ce(NO3)3 solution during the process.
[0028] 〔Example 3〕: Cu-Zn-Al-In / Ce (Catalyst III)
[0029] Liquids A and B are added to liquid C, which is being stirred at a rate of 10 mL / min. After stirring for 24 hours, the mixture is filtered to obtain a filter cake. The filter cake is then washed several times with deionized water to remove sodium ions, dried at 110°C, and then calcined at 600°C to produce catalyst precursor I. After waiting until it reaches room temperature, 10 g of catalyst precursor I is placed in a pear-shaped flask, 0.026 g of In(NO3)3 solution and 0.031 g of Ce(NO3)3 solution are added, and the mixture is extracted and dried using a rotary evaporator. After drying at 110°C, it is calcined at 600°C to produce catalyst III.
[0030] Catalyst III in Example 3 incorporates a first modifier composed of indium (In) or its oxide and cerium (Ce) or its oxide by adding 0.026 g of In(NO3)3 solution and 0.031 g of Ce(NO3)3 solution during the process.
[0031] [Comparative example 1]: Cu-Zn-Al (catalyst IV)
[0032] Liquids A and B are added to liquid C, which is being stirred at a rate of 10 mL / min. After stirring for 24 hours, the mixture is filtered to obtain a filter cake. The filter cake is then washed several times with deionized water to remove sodium ions, dried at 110°C, and then calcined at 600°C to produce catalyst IV.
[0033] In comparison with Examples 1-3, Catalyst IV of Comparative Example 1 does not contain indium (In) or its oxides, nor cerium (Ce) or its oxides; that is, it does not contain the first modifier.
[0034] [Comparative example 2]: Cu-Zn-Al-Zr-Ga (catalyst V)
[0035] Liquids A' and B are added to liquid C, which is being stirred at a rate of 10 mL / min. After stirring for 24 hours, the mixture is filtered to obtain a filter cake. The filter cake is then washed several times with deionized water to remove sodium ions, dried at 110°C, and then calcined at 600°C to produce catalyst V.
[0036] In comparison with Examples 1-3, Catalyst V of Comparative Example 2 does not contain indium (In) or its oxides, nor cerium (Ce) or its oxides; that is, it does not contain the first modifier.
[0037] [Examples 4-12 and Comparative Examples 3-4]: Converting CO2 to methanol using catalysts I-V
[0038] As shown in Table 1, to carry out the hydrogenation reaction, the catalysts generated in each of the above examples are placed in a fixed-bed reactor, and H2 / CO2 (molar ratio 3 / 1) is added to adjust the reaction conditions (space velocity (GHSV), temperature (T), pressure (P)). Product component analysis is performed using online gas chromatography (online GC), and the CO2 conversion rate (%), CO selectivity (%), methanol selectivity (%), and methanol production rate (%) are calculated, and the results are shown in Table 1.
[0039] [Table 1]
[0040] Here, methanol production rate (%) = CO2 conversion rate (%) × methanol selectivity (%). The higher the CO2 conversion rate or methanol selectivity, the higher the methanol production rate. Since CO is not a necessary product, a lower CO selectivity is desirable.
[0041] As can be seen from Table 1, under the same reaction conditions, Examples 4 and 5 (using the catalyst for converting carbon dioxide to methanol containing the first reforming agent from Examples 1 and 2) showed significantly higher CO2 conversion rates, methanol selectivity, and methanol production rates compared to Comparative Examples 3 and 4 (using the catalyst for converting carbon dioxide to methanol containing the first reforming agent from Comparative Examples 1 and 2). In addition, under different space velocities (GHSV), Examples 6 to 9 (using the catalyst for converting carbon dioxide to methanol containing the first reforming agent from Examples 1 and 2) could similarly achieve higher CO2 conversion rates, methanol selectivity, and methanol production rates compared to Comparative Examples 3 and 4.
[0042] These results indicate that catalysts I (Cu-Zn-Al-In) and II (Cu-Zn-Al-Ce), provided in Examples 1 and 2 of the present invention, which undergo In or Ce modification (i.e., include the first modifying agent), perform better than catalysts IV (Cu-Zn-Al) and V (Cu-Zn-Al-Zr-Ga), which have not undergone In or Ce modification (i.e., do not contain the first modifying agent) in Comparative Examples 1 and 2.
[0043] Under different space velocities (GHSV), Examples 10-12, compared to Comparative Example 3, achieved higher CO2 conversion rates, methanol selectivity, and methanol production rates by using Catalyst III (Cu-Zn-Al-In / Ce) containing the first modifier of Example 3. These results indicate that Catalyst III (Cu-Zn-Al-In / Ce) of Example 3, which is simultaneously modified with In and Ce, has better performance compared to Catalyst I (Cu-Zn-Al-In) and Catalyst II (Cu-Zn-Al-Ce) of Examples 1 and 2, which are modified with In or Ce alone.
[0044] In a preferred embodiment, the catalyst for converting carbon dioxide to methanol according to the present invention may further include a second modifier selected from the group consisting of gallium (Ga) or its oxides and zirconium (Zr) or its oxides, thereby further improving its performance, but the present invention is not limited thereto.
[0045] While the present invention has disclosed best embodiments above, as those skilled in the art will understand, these embodiments are used solely for illustrative purposes and should not be understood as limiting the scope of the invention. It should be noted that all modifications and substitutions having equivalent effects to those in these embodiments are included within the scope of the invention. Therefore, the scope of protection of the present invention is as defined in the claims. [Explanation of Symbols]
[0046] Nothing.
Claims
1. A catalyst for converting carbon dioxide to methanol, 30 to 70 parts by weight of copper (Cu) or its oxide, 20 to 50 parts by weight of zinc (Zn) or its oxide, 2 to 10 parts by weight of aluminum (Al) or its oxide, The first modifier comprises 0.1 to 10 parts by weight of a first modifier, wherein the first modifier is selected from the group consisting of indium (In) or its oxides and cerium (Ce) or its oxides. A catalyst for converting carbon dioxide to methanol, characterized by the following features.
2. The catalyst for converting carbon dioxide to methanol according to claim 1, characterized in that the first modifier is indium (In) or an oxide thereof, and the content of indium (In) or an oxide thereof is 0.05 wt% to 5 wt% based on the total weight of copper (Cu) or an oxide thereof, zinc (Zn) or an oxide thereof, aluminum (Al) or an oxide thereof, and the first modifier.
3. The catalyst for converting carbon dioxide to methanol according to claim 1, characterized in that the first modifier is cerium (Ce) or an oxide thereof, and the content of cerium (Ce) or an oxide thereof is 0.05 wt% to 5 wt% based on the total weight of copper (Cu) or an oxide thereof, zinc (Zn) or an oxide thereof, aluminum (Al) or an oxide thereof, and the first modifier.
4. The catalyst for converting carbon dioxide to methanol according to claim 1, characterized in that the first modifier is composed of indium (In) or its oxide and cerium (Ce) or its oxide, and the content of indium (In) or its oxide and cerium (Ce) or its oxide is independently 0.05 wt% to 5 wt% based on the total weight of copper (Cu) or its oxide, zinc (Zn) or its oxide, aluminum (Al) or its oxide, and the first modifier.
5. A catalyst for converting carbon dioxide to methanol according to any one of claims 1 to 4, further comprising a second reforming agent selected from the group consisting of gallium (Ga) or its oxides and zirconium (Zr) or its oxides.
6. A method for preparing methanol, A step of introducing a catalyst for converting carbon dioxide to methanol according to any one of claims 1 to 4 into a fixed-bed reactor, Hydrogen (H ２ A step of introducing ) and carbon dioxide gas into the fixed-bed reactor, carrying out a hydrogenation reaction under the action of a catalyst for converting the carbon dioxide to methanol, and producing methanol, A method for preparing methanol, characterized by containing [a certain substance].
7. The space velocity (GHSV) of the hydrogenation reaction is 3,000 to 20,000 h. -１ The preparation method according to claim 6, characterized in that it is between the following conditions.
8. The preparation method according to claim 6, characterized in that the temperature of the hydrogenation reaction is between 200 and 300°C.
9. The pressure of the hydrogenation reaction is 30-80 kg / cm². ２ The preparation method according to claim 6, characterized in that it is between the following conditions.
10. A method for preparing methanol, A step of introducing the catalyst for converting carbon dioxide to methanol according to claim 5 into a fixed-bed reactor, Hydrogen (H ２ A step of introducing ) and carbon dioxide gas into the fixed-bed reactor, carrying out a hydrogenation reaction under the action of a catalyst for converting the carbon dioxide to methanol, and producing methanol, A method for preparing methanol, characterized by containing [a certain substance].
11. The space velocity (GHSV) of the hydrogenation reaction is 3,000 to 20,000 h. -１ The preparation method according to claim 10, characterized in that it is between the above.
12. The preparation method according to claim 10, characterized in that the temperature of the hydrogenation reaction is between 200 and 300°C.
13. The pressure of the hydrogenation reaction is 30-80 kg / cm². ２ The preparation method according to claim 10, characterized in that it is between the above.