Method and apparatus for producing carbon monoxide

Abstract

The present invention discloses a method for producing carbon monoxide, the method comprising the step of producing carbon monoxide by decomposing at least one of formic acid or alkyl formic acid esters in the presence of a catalyst containing a parent material and an acid group chemically bonded to the parent material.

Description

Technical Field

[0001] This disclosure relates to a method and apparatus for producing carbon monoxide. Prior Technology

[0002] Formic acid and alkyl formic acid esters produce carbon monoxide through decomposition. As a method for producing carbon monoxide from formic acid, for example, a method using a zeolite-based catalyst pre-modified with mineral acid is known (Patent Document 1). [Previous Technical Documents] [Patent Literature]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-007413 Summary of the Invention

[0004] [The problem that the invention aims to solve]

[0005] This disclosure relates to a new method for producing carbon monoxide from formic acid or alkyl formic acid esters. [Technical means to solve the problem]

[0006] One aspect of this disclosure relates to a method for producing carbon monoxide, the method comprising the step of producing carbon monoxide by decomposing at least one of formic acid or alkyl formic acid esters in the presence of a catalyst containing a parent material and acid groups chemically bonded to the parent material.

[0007] Another aspect of this disclosure relates to a carbon monoxide manufacturing apparatus, comprising: a reactor; and a catalyst disposed within the reactor, and comprising a precursor material and acid groups chemically bonded to the precursor material. [Effects of the Invention]

[0008] The method or apparatus disclosed herein can effectively produce carbon monoxide. Regarding the method or apparatus disclosed herein, since less acidic component is dissolved from the catalyst, it also has advantages in terms of reaction stability, ease of wastewater treatment, and inhibition of equipment corrosion. Simple Explanation of the Diagram

[0009] [Figure 1] is a schematic diagram showing one embodiment of the carbon monoxide manufacturing apparatus disclosed herein. Implementation

[0010] The following describes several embodiments of this disclosure in detail. However, this disclosure is not limited to these embodiments.

[0011] The disclosed method for producing carbon monoxide includes the step of generating carbon monoxide by decomposing at least one of formic acid or alkyl formic acid esters in the presence of a catalyst comprising a parent material and an acid group chemically bonded to the parent material.

[0012] The raw material compound can be formic acid, alkyl formic acid esters, or combinations thereof. Alkyl formic acid esters can be, for example, methyl formic acid or ethyl formic acid esters.

[0013] The base material constituting the catalyst can be porous. The base material can be a non-metallic material, such as activated carbon, silicone, and perfluorocarbons. If the base material is non-metallic, it inhibits the deterioration of the catalyst accompanying metal leaching and reduces the mixing of metal impurities into the carbon monoxide.

[0014] The acid group constituting the catalyst can be, for example, a sulfonic acid group, a carboxyl group, a hydroxyl group, or a combination thereof, or it can be a sulfonic acid group. The sulfonic acid group can be easily incorporated into the parent material, such as a non-metallic material, through chemical bonding. For example, the sulfonic acid group (-SO₃H) can bond with the compounds constituting the parent material through a single bond. When the acid group constituting the catalyst is a sulfonic acid group, it is preferable to use activated carbon as the parent material. In this case, the catalyst activity and reaction efficiency are improved, and costs can be controlled.

[0015] From the perspective of improving the conversion rate of the reaction, the amount of acid groups in the catalyst per 1g of catalyst containing the parent material and acid groups can be 0.03 mmol or more, or 0.04 mmol or more, or 0.05 mmol or more. The amount of acid groups in the catalyst per 1g of catalyst can be less than 1.0 mmol, less than 0.50 mmol or less, or less than 0.10 mmol.

[0016] Catalysts with acid groups introduced through chemical bonding can be synthesized using conventional methods, or commercially available catalysts can be used.

[0017] For example, a reaction that produces carbon monoxide can be carried out by contacting a gas or liquid containing a raw material compound with a catalyst in a reactor. A carbon monoxide production apparatus equipped with a reactor and a catalyst disposed within the reactor can be prepared in advance, and a gas or liquid containing a raw material compound can be supplied into the reactor.

[0018] The feedstock compound can be commercially available formic acid or alkyl formic acid esters. A gas containing the vapor of the feedstock compound can be generated from the solution containing the feedstock compound and supplied to the reactor. Alternatively, the solution containing the feedstock compound can also be supplied to the reactor. Supplying a gas containing the feedstock compound tends to have superior reaction efficiency. The concentration of the feedstock compound solution is not particularly limited, but from an energy efficiency point of view, it can be 40% by mass or more based on the mass of the solution. The feedstock compound solution can be, for example, an aqueous solution of formic acid.

[0019] For an efficient reaction, the catalyst, the reactant compound, or both can be heated. For example, if the heating temperature is 100–300°C, there is a tendency to suppress the formation of byproducts such as hydrogen and to carry out the reaction particularly efficiently. From the same point of view, the heating temperature can be 100–150°C.

[0020] The reactor can be, for example, a reaction vessel or a reaction tower. A gas containing the raw material compound can be continuously supplied to the reaction tower, which is a reactor equipped with a catalyst. With the continuous supply of gas, carbon monoxide can be continuously produced. There can be one reaction tower or multiple reaction towers connected together. A reactor composed of multiple reaction towers is advantageous in suppressing deviations in the flow rate distribution within the reactor and ensuring sufficient heat transfer area for heating. Instead of using a reaction tower, a catalyst and a gas or liquid containing the raw material compound can be placed inside the reactor (reaction vessel), and then the catalyst and the gas or liquid containing the raw material compound are heated.

[0021] The reactor can be made of, for example, non-metallic materials such as carbon. Reactors made of non-metallic materials are less susceptible to corrosion caused by formic acid and carbon monoxide, and are less likely to affect the reaction. Reactors with surfaces treated with glass linings are readily applicable when heating temperatures are relatively low (e.g., 100-150°C). When a gas or liquid containing the feed compound is continuously supplied to the reactor, the reactor typically has inlets and outlets for supplying or discharging the gas or liquid, and these inlets and outlets are connected to an external flow path.

[0022] When a gas containing a raw material compound is continuously supplied to the reactor, the supply rate of the raw material compound is appropriately adjusted according to the amount of acid groups, etc. For example, the supply rate of the raw material compound can be in the range of 0.1 to 1000 [1 / hour].

[0023] The resulting carbon monoxide-containing gas or liquid typically contains trace amounts of hydrogen, carbon dioxide, and methane, in addition to water. Therefore, the carbon monoxide production method may further include: a step of removing unreacted feedstock compounds and byproducts from the carbon monoxide-containing product (gas or liquid) taken from the reactor; and a step of removing water from the product. Feedstock compounds and byproducts can be removed by conventional washing methods, thereby obtaining high-purity carbon monoxide. Feedstock compounds and carbon dioxide can be easily removed, for example, with caustic soda. The purity of carbon monoxide in the product after these steps, after removing water, feedstock compounds, and byproducts, can be above 99.99%. This high-purity carbon monoxide can be used in various applications, including semiconductor manufacturing.

[0024] Figure 1 is a schematic diagram showing one embodiment of the carbon monoxide manufacturing apparatus disclosed herein. As shown in Figure 1, the carbon monoxide manufacturing apparatus 10 disclosed herein includes a reactor 1 and a catalyst 2 disposed within the reactor 1. The catalyst 2 comprises a base material and acid groups chemically bonded to the base material. Furthermore, the reactor 1 has an inlet 1a and an outlet 1b for supplying or discharging gas or liquid. Outside the reactor 1, a flow path 3 for supplying at least one of formic acid or alkyl formic acid esters is connected to the inlet 1a, and a flow path 4 for discharging gas or liquid is connected to the outlet 1b. The carbon monoxide manufacturing apparatus 10 may, as needed, further include a heating device (not shown) for heating the catalyst 2, the base compound, or both, a device (not shown) for removing unreacted base compound and byproducts from the product containing carbon monoxide, and a device (not shown) for removing water from the product.

[0025] In the carbon monoxide manufacturing apparatus 10, a raw material compound is supplied to the reactor 1 through inlet 1a via flow path 3 and passes through catalyst 2. In the presence of the catalyst, carbon monoxide is generated by the decomposition of the raw material compound. The product containing carbon monoxide is discharged from outlet 1b of the reactor 1 through flow path 4. This is how carbon monoxide is manufactured. [Example]

[0026] The following examples illustrate this disclosure in more detail. However, this disclosure is not limited to these examples.

[0027] Example 1 A catalyst containing activated carbon and sulfonic acid groups chemically bonded to the activated carbon (manufactured by FUTAMURA CHEMICAL CO.,LTD., trade name: CE20-96142DH, sulfonic acid group content: 0.05~0.10 mmol per 1g catalyst (containing activated carbon and sulfonic acid groups)) was prepared. 25g of this catalyst was packed into a column with an inner diameter of 2.5cm and a length of 25cm. The catalyst-filled column was externally heated to 140°C, and formic acid vapor at 120°C, generated by passing a 76% by weight formic acid aqueous solution through a vaporizer, was fed from one end of the column at a supply rate of 6g / h. The gas exiting from the other end of the column was sequentially passed through a 20% by weight caustic soda aqueous solution and then water. The caustic soda aqueous solution removed trace amounts of carbon dioxide from the gas. After the gas passing through a caustic soda solution and water was cooled and dried, the hydrogen content in the gas was quantified using a gas chromatography system equipped with a PDD (Pulsed Discharge Detector). Based on the calculated hydrogen content and gas flow rate, the conversion rate of formic acid and the selectivity for carbon monoxide were determined. The conversion rate was 21%, and the selectivity for carbon monoxide was over 99.99%.

[0028] To examine the detachment of sulfonic acid groups from the aforementioned catalyst, 10 g of unused catalyst was immersed in 50 mL of water at room temperature for 1 hour. Based on the analysis results of ion chromatography, the total detachment of SO₄²⁻ and SO₃⁻ was 0.012 mmol / g. Since the sulfonic acid groups are chemically bonded to the activated carbon used as the parent material, it was confirmed that the sulfonic acid groups hardly detach when the catalyst is immersed in water.

[0029] Comparative Example 1 22 g (50 mL) of granular activated carbon (manufactured by Takeda Pharmaceutical Company Limited, trade name: Shirasagi G2X) without sulfonic acid groups was packed into a 10 cm long column. Except for the use of this packed column, a carbon monoxide generation test was performed in the same manner as in Example 1. Analysis of the gas discharged from the column confirmed that no carbon monoxide was generated.

[0030] 10g of unused catalyst was immersed in an aqueous sulfuric acid solution containing 0.05 mmol of sulfuric acid per 1g of catalyst (activated carbon) and sulfuric acid. The catalyst removed from the sulfuric acid solution was then immersed in 50mL of water at room temperature for 1 hour. Subsequent analysis using ion chromatography showed a total removal of 0.048 mmol / g of SO₄²⁻ and SO₃⁻. Based on this result, it was confirmed that the sulfuric acid introduced through immersion in the aqueous sulfuric acid solution did not substantially form chemical bonds with the activated carbon, which served as the parent material.

[0031] 1: Reactor 1a: Entrance 1b: Export 2:Catalyst 3,4:Flow path 10: Carbon monoxide manufacturing equipment

Claims

1. A method for producing carbon monoxide, the method comprising the step of generating carbon monoxide by decomposing at least one of formic acid or alkyl formic acid ester in the presence of a catalyst comprising a parent material and an acid group chemically bonded to the parent material, wherein the acid group is a sulfonic acid group, the parent material is a non-metallic material comprising activated carbon, and the amount of the acid group in the catalyst is 0.03 mmol or more per 1 g of the catalyst.

2. As in request item 1, where, In every 1g of the aforementioned catalyst, the amount of the aforementioned acid group in the aforementioned catalyst is less than 1.0 mmol.

3. As in request item 1 or request item 2, wherein, In the step of generating carbon monoxide by decomposing the aforementioned raw material compounds, the aforementioned catalyst is heated to 100-300°C.

4. The method of request item 1 or request item 2, wherein, The aforementioned catalyst is disposed in the reactor, and a gas or liquid containing the aforementioned raw material compound is supplied to the aforementioned reactor.

5. A carbon monoxide manufacturing apparatus comprising: a reactor; and a catalyst disposed within the reactor, comprising a precursor material and acid groups chemically bonded to the precursor material, wherein the acid groups are sulfonic acid groups, the precursor material is a non-metallic material, the non-metallic material comprises activated carbon, and the amount of the acid groups in the catalyst is 0.03 mmol or more per 1g of the mass of the catalyst.

6. As in claim 5, a carbon monoxide manufacturing apparatus, wherein, In every 1g of the aforementioned catalyst, the amount of the aforementioned acid group in the aforementioned catalyst is less than 1.0 mmol.

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