JP2919633B2 - Method for producing partial oxide of propylene - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION Acetone, acrolein, acrylic acid and the like, which are partial oxides of propylene, are extremely important intermediates in the field of production of organic industrial chemicals, and are in great demand as solvents and the like.

According to the present invention, a partial oxide of propylene such as acetone, acrolein and acrylic acid is produced from propylene, water and an oxidizing compound by a fuel cell system using an ion conductor provided with a catalyst electrode, and at the same time as necessary. The present invention relates to a method for extracting electric energy. More specifically, unlike ordinary fuel cell systems, propylene, water, and oxidizable compounds are produced by a non-membrane fuel cell system in which the oxidizing side and the reducing side are not separated by a partition but are mixed with an oxidizing substance and a substance to be oxidized. To produce propylene partial oxides such as acetone, acrolein, acrylic acid, and the like.

[0003]

2. Description of the Related Art Propylene partial oxides such as acetone, acrolein and acrylic acid are used in the gas phase catalytic oxidation of propylene, by-products in the production of phenol by the cumene method, and oxygen or air oxidation in the presence of water by the Wacker method. Is obtained from Among them, the direct oxidation of propylene by the so-called Wacker method using a redox catalyst comprising palladium chloride and copper chloride is an industrially important method for producing acetone. This method is industrially performed by blowing gaseous ethylene and oxygen or air into a hydrochloric acid aqueous solution containing a catalytic amount of palladium chloride and a large excess of copper chloride, using a reactor made of a high corrosion-resistant material such as titanium. However, a) Since the reaction is a homogeneous reaction, it is necessary to separate the product and the catalyst. b) Since hydrochloric acid is added to and reacted with a chloride catalyst such as palladium chloride or copper chloride, the reactor is highly corroded and a chlorine-containing compound is by-produced. There are problems such as.

There is also known a method in which a voltage is applied to an electrode to electrochemically oxidize an olefin to obtain a carbonyl compound such as an aldehyde or a ketone. Product selectivity is low. In addition, recently, attempts have been made to synthesize a useful chemical substance using a fuel cell system without applying a voltage. For example, Electrochemical Agent Act has been attempted.
a. Vol. 32 No8, pp1137-1143
(1987) describes a method in which an aqueous phosphoric acid solution is caused to flow between polybenzimidazole films, only propylene is allowed to flow to one of palladium electrodes provided on both sides thereof, and oxygen is caused to flow to the other. The products obtained are acrolein, acrylic acid, carbon dioxide and the like, the selectivity of the products is low, and in addition, there is almost no formation of acetone. Also, as an example of producing acetone from propylene using a similar fuel cell system, there is only Japanese Patent Application No. 63-246062 filed earlier by the present inventors. In this patent, both catalyst electrodes are separated by an ion conductor membrane, and are produced by a membrane fuel cell system in which propylene and oxygen are not mixed, and the product is produced when no voltage is applied. Acetone is the most,
Other partial oxides are not selectively produced. In addition, the method of using a non-diaphragm fuel cell system, in which the reaction proceeds in a mixed state of propylene and oxygen or an oxidizing compound as a simple reactor without separating the electrode chamber by a diaphragm as in the present invention, is described. Not known by.

[0005]

SUMMARY OF THE INVENTION The present invention uses a fuel cell system to remove not only acetone but also other partial propylene oxides such as acrolein from propylene, water, oxygen and / or oxidizing substances. By selectively manufacturing, it is possible to solve problems such as separation of a product and a catalyst in a conventional manufacturing method, corrosion of materials, and by-product of a chlorine-containing compound, and in addition, a conventional fuel cell system has An object of the present invention is to solve many problems such as a complicated reactor and form such as a diaphragm or the like, or the main product is acetone alone and cannot form other partial oxides selectively.

[0006]

According to the present invention, as shown in FIG. 1, an electrode made of at least one selected from the group consisting of palladium metal and palladium compound and an electrode B made of ruthenium on an ion conductive material. , Platinum, iridium, rhodium and at least one electrode selected from the compounds of these metals, both electrodes are directly installed without direct contact, and both electrodes are connected by a conductive wire or a conductive material. And a mixture of propylene, water and oxygen or an oxidizing compound is brought into contact therewith, and using a non-diaphragm type fuel cell system, a partial oxide of propylene such as acetone or acrolein is selectively used as one of the compounds. It is a method of extracting power energy as needed at the same time as manufacturing.

As the oxidizing compound used in the method of the present invention, any compound which can react with hydrogen on the catalyst electrode of the present invention can be used, but oxygen or air is generally used. If necessary, these can be used after being diluted with another medium. Also,
It is also possible to use a reducible compound as the oxidizing compound and simultaneously carry out a hydrogenation reaction. In the method of the present invention, power energy corresponding to a change in free energy of the reaction can be extracted from the reaction system as needed. The electrode A used in the method of the present invention is an electrode selected from palladium and a palladium compound, and the electrode B is an electrode selected from ruthenium, platinum, iridium, rhodium and a compound of these metals. Compounds of these metals include metal halides, metal nitrates, metal sulfates, metal oxides, metal phosphates, metal ammonium compounds, metal acetylacetones,
Metal acetate, metal carbonyl compound and the like can be mentioned. Of course, the method of the present invention is not limited to only these compounds. In preparing these electrodes, the above-mentioned metal and / or metal compound can be mixed or supported on a conductive substance, for example, graphite, activated carbon, carbon whisker or the like. Further, when molding the electrode, various binders, for example, Teflon or the like can be mixed and heated and used. However, the method of the present invention is not limited only to these preparation methods and molding methods.

The ionic conductor used in the method of the present invention is a solid known as a protonic acid such as phosphoric acid, hydrochloric acid, sulfuric acid or the like, a heteropolyacid, H-mordenite, H-montmorillonite, zirconium phosphate or the like. An electrolyte, a perovskite-type solid solution containing SrCeO ₃ as a matrix, or the like can be used. Further, those based on a fluoropolymer such as perfluorocarbon, into which one or two sulfonic acid groups or carboxylic acid groups are introduced, such as Nafion (registered trademark of Du Pont)
Can also be used. A liquid such as phosphoric acid can be used by impregnating it with silica wool or the like, or can be used by sandwiching it between ion-permeable filters or membranes.

In the method of the present invention, the electrodes A and B are attached to these ionic conductors, but both electrodes are not brought into direct contact with each other, and these electrodes are connected by a conductive wire or an electrically conductive material. Do it. Thereby, electric energy is taken out from between the two electrodes to the outside and the reaction proceeds smoothly. The conductive wire or the electrically conductive substance used in the present invention can be used as long as it is a substance that conducts electric current, and is not particularly limited, but is easily available, and gold, silver, and copper wires from the viewpoint of high electrical conductivity and the like. Is recommended.

The propylene, water and oxidizing compound supplied in the process of the present invention are usually gas or liquid, and may be dissolved in an inert medium (liquid, gas) if necessary.
It may be diluted by mixing or the like and brought into contact with the catalyst electrode. The reaction temperature is usually from -20 ° C to 200 ° C, particularly preferably from -5 ° C to 150 ° C. Further, the reaction is generally carried out at normal pressure, but can be carried out under increased or reduced pressure as required.

Further, in the method of the present invention, when performing a non-diaphragm fuel cell reaction, by changing the metal or metal compound constituting the electrode B, one of acetone and acrolein, which are partial oxides of propylene, is selected. It can be manufactured in a special way. For example, when the electrode B is a catalyst electrode composed of rhodium metal, ruthenium metal, platinum metal and a compound of these metals, acrolein is selectively generated, and the electrode B is composed of iridium and an iridium compound. In this case, acetone is obtained as the main product. The reaction product can be separated and purified by ordinary methods such as distillation to obtain high-purity acetone, acrolein and the like.

[0012]

The present invention will be specifically described below with reference to examples. However, the reaction method and the reaction apparatus are illustrative, and the present invention is not limited to the examples.

Example 1-4 Disk-shaped silica wool (thickness: 1.0 mm, diameter: 21 mm)
mm), a 50% graphite powder, 5 mg of Teflon powder and 20 mg of palladium black powder were mixed well as an electrode A as shown in FIG. 1 and then formed into a sheet by hot pressing. The electrode was mounted on one side of the disk, and 50 mg of graphite powder, 5 mg of Teflon powder, and 20 mg of metal powder were formed as electrodes B in the same manner as electrode A, and rhodium-graphite (Example 1) and ruthenium-graphite (Example 2). ), Platinum-graphite (Example 3) and iridium-graphite (Example 4) electrodes were prepared and mounted as electrodes B in each example on the other of the disks as shown in FIG. Electrode A
After connecting the electrode B with a gold wire, the reaction temperature was set to 80 ° C., and propylene, oxygen, and steam were each supplied at 16 ml / min.
/ Min and a mixed gas of 5 ml / min were supplied to perform a partial oxidation reaction of ethylene. As shown in Table 1, when the electrode B was reacted with rhodium-graphite, ruthenium-graphite, and platinum-graphite, acrolein was obtained at an extremely high generation rate and selectivity. -In the case of graphite, acetone was produced at a high production rate as the main product.

Comparative Example 1-4 A partial oxidation reaction of propylene was carried out under exactly the same conditions as in Example 1-4 except that the electrodes A and B were not connected with gold wires. As a result, as shown in Table 1, the production of propylene partial oxide was reduced. From these results, it can be seen that the present invention greatly contributes to the fuel cell system.

[0015]

[Table 1] 添加 Addition of electrode B Current value Generation rate (mmol / min) ) Metal mA Acrolein Acetone Acrylic acid ─────────────────────────────────── Example 1 Rhodium 4.00 0.58 0.03 0.03 Example 2 Ruthenium 3.5 0.45 0.03 0.03 Example 3 Platinum 1.8 0.42 0.03 0.04 Example 4 Iridium 2.3 0.32 0.41 0.01 Comparative Example 1 Rhodium --- 0.25 0.03 0.03 Comparative Example 2 Ruthenium --- 0.13 0.01 0.01 Comparative Example 3 Platinum --- 0.35 0. 02 0.04 Comparative Example 4 Iridium 0.14 0.34 0.01 ──────────────────

[0016]

According to the method of the present invention, a) the heterogeneous reaction is performed, and therefore, the product and the catalyst can be easily separated, as compared with the conventional production method by the Wacker method or the like. b) Since no corrosive chloride is used, the reactor can be made inexpensive and simple. c) There are no by-products such as chlorinated products. d) Compared to conventional fuel cell reactors, no diaphragm is required, resulting in a simpler structure and easier operation. f) If necessary, energy can be extracted as electric power together with the product. In addition, according to the method of the present invention, it is possible to obtain either acetone or acrolein which is a partial oxide of propylene at a high selectivity by selecting a catalyst electrode. .

[Brief description of the drawings]

 FIG. 1 is a schematic diagram of a non-diaphragm fuel cell system.

FIG. 1 is a schematic diagram of a non-diaphragm fuel cell system.

[Explanation of symbols]

 Reference Signs List 1 electrode A 2 electrode B 3 ion conductive material 4 conductive material 5 ammeter 6 voltmeter

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B01J 27/25 B01J 27/25 X 31/04 31/04 X 31/12 31/12 X C07C 27/12 330 C07C 27/12 330 45/35 45/35 47/22 47/22 F 49/08 49/08 A C25B 3/02 C25B 3/02 H01M 8/06 H01M 8/06 R // C07B 61/00 300 C07B 61/00 300

Claims (3)

(57) [Claims] 1. An electrode made of at least one selected from the group consisting of palladium metal and a palladium compound as an electrode A and an electrode B selected from ruthenium, platinum, iridium, rhodium and these metal compounds on an ion conductor material. An electrode composed of at least one or more
A non-diaphragm fuel cell characterized in that both electrodes are attached so as not to be in direct contact with each other, and both electrodes are connected by a conductive wire or a conductive material, and a mixture of propylene, water and an oxidizing compound is brought into contact with the two electrodes. A method for producing a partial oxide of propylene by a system. 2. The method according to claim 1, wherein a voltage is applied to both electrodes. 3. The metal compound is at least one compound selected from metal halides, metal nitrates, metal sulfates, metal oxides, metal hydroxides, metal phosphates and metal ammonium salts. 2. The method according to 1.