JP2004314041A - Magnetized cobalt fluidized bed catalyst for hydrogenation reaction and method for using the catalyst - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a magnetized nickel fluidized bed catalyst for hydrogenation reaction having sufficiently high catalytic activity, excellent in settling properties, easily separated, recovered and recycled and reduced in the lowering of settling properties even if used repeatedly. <P>SOLUTION: A cobalt fluidized bed catalyst for hydrogenation reaction comprises cobalt particles of which the crystal size in a crystal lattice surface (111) by an X-ray diffraction method is 2.0-10.0 nm and magnetized by applying a magnetic field with a magnetic flux density of 0.1×10<SP>-4</SP>-30 T to the catalyst. When the magnetized catalyst is used in liquid phase reaction, it shows a sufficient catalytic effect, can easily be precipitated and recovered after reaction, and the recovered catalyst can be used repeatedly. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a magnetized cobalt fluidized bed catalyst for hydrogenation reaction and a method for using the same. More specifically, the present invention is a magnetized cobalt fluidized bed for hydrogenation reaction which has sufficiently high catalytic activity for practical use, has good sedimentation of the catalyst in a liquid phase hydrogenation reaction system, and is easy to separate and recover. The present invention relates to a catalyst and a method for using the same.

  Teruo Kubo and Shinichiro Komatsu, "Raney catalyst" (Kyoritsu Shuppan, 1971, Non-Patent Document 1) include a metal having a catalytic action (metal A) such as nickel, cobalt, copper, iron, silver, palladium, etc. Metals to be eluted (metal B) For example, from an alloy with aluminum, silicon, zinc, and magnesium (Raney alloy), using an erosion agent, for example, water, an alkali, an acid, etc. (usually, an alkali is used). A catalyst containing a sponge-like active metal as a main component, that is, a sponge metal catalyst obtained by a step of eluting a metal (B metal) (hereinafter referred to as a developing step) is described in detail. The sponge cobalt catalyst means a sponge catalyst when the metal A is cobalt.

Generally, a sponge metal catalyst is obtained by charging an alloy powder (hereinafter, referred to as a master alloy) selected from at least one of A metal and B metal into an aqueous solution of sodium hydroxide, at a predetermined temperature for a predetermined time, Manufactured by heating and stirring to elute at least a part of the B metal and washing with water, and stored in water.
The water washing at the time of producing the sponge metal catalyst is performed about 3 to 20 times to remove the metal and excess alkali eluted in the developing step. However, if the sedimentation of the catalyst particles is poor, the catalyst is mixed into the washing water. Sometimes. In order to remove the catalyst in the washing wastewater, additional equipment such as a filter and a sedimentation tank was required, and the operation was complicated due to the long time required for the sedimentation of the catalyst, leading to an increase in cost. .

The cobalt fluidized bed catalyst used in the liquid phase reaction is separated from the liquid phase by a method such as sedimentation separation, filtration separation, centrifugation, magnetic capture, or a combination thereof. In this case, each of the above methods requires a sedimentation tank, a filter, a centrifuge, a magnetizing device (electromagnet or permanent magnet), and the like. When the separated and recovered catalyst is reused, the filtration separation method or the centrifugal separation method is not industrially advantageous because a large amount of labor is required for the recovery and reuse of the catalyst. When the sedimentation speed of a cobalt fluidized bed catalyst or the like is high, it is practically preferable to use the sedimentation separation method.
However, it may take a long time to settle and separate the conventional cobalt fluidized bed catalyst only by gravity, and when the catalyst particle size is small and the liquid phase has a high viscosity, the separation efficiency is greatly reduced. Therefore, it was sometimes difficult to implement it industrially.

  Further, a method of applying a magnetic field to these catalysts together with gravity in order to separate and recover and reuse the cobalt fluidized bed catalyst is known. Japanese Patent Publication No. 39-9865 (Patent Document 1) discloses that most of a magnetic metal fluidized bed catalyst in a reaction solution is separated by gravity, and further passed through a magnetic field to capture the remaining catalyst and to eliminate the magnetic field. A contact continuous reaction method in which the magnetization is released and recovered in a reactor is disclosed. In Japanese Patent Publication No. 45-20884 (Patent Document 2), a cooling device, a separator in which an electromagnet is applied to at least a part of a wall surface, a slurry pump or a gas injector are installed downstream of the reactor. There has been proposed a continuous contacting reactor in which a nickel catalyst suspended in a liquid is separated and recovered and used.

The method of applying a magnetic field to the magnetic metal fluidized bed catalyst to separate it from the liquid phase depends on the magnetic metal catalyst to be applied with the magnetic field and the viscosity of the liquid phase in which the magnetic field is suspended, and the sedimentation time becomes practically satisfactory. May not be shortened, and there is a problem that a large-scale special device and equipment are required for applying a magnetic field.
Furthermore, depending on the type of the sponge metal catalyst, it may be hardened during storage and may be difficult to be charged into a reaction tank or the like.

Teruo Kubo, Shinichiro Komatsu, Raney Catalyst, Kyoritsu Shuppan, 1971, pp. 1-103 JP-B-39-9865, pages 1 to 5 Japanese Patent Publication No. 45-2088, pages 1 to 4

  The present invention has a sufficiently high catalytic activity for practical use, and has excellent sedimentation properties, and can be easily separated, recovered and reused without special equipment. An object of the present invention is to provide a magnetized hydrogenated cobalt fluidized bed catalyst for hydrogenation reaction, which has a small decrease and does not or hardly solidify during storage, and a method of using the same.

The magnetized cobalt fluidized bed catalyst for hydrogenation reaction of the present invention is at least selected from cobalt particles having a cobalt crystallite diameter of 2.0 to 10.0 nm at a crystal lattice plane (111) measured by an X-ray diffraction method. It is characterized by being composed of one type of fluidized cobalt fluidized bed catalyst particles for hydrogenation reaction and magnetized by application of a magnetic field having a magnetic flux density of 0.1 × 10 ^{−4 to} 30 T.
In the magnetized cobalt fluidized bed catalyst for hydrogenation reaction of the present invention, the cobalt particles preferably have a cobalt crystallite diameter of 3.0 to 10.0 nm on a crystal lattice plane (111).
In the magnetized cobalt fluidized bed catalyst for hydrogenation reaction of the present invention, it is preferable that at least one of the cobalt particles has a sponge-like form.
The method of using the magnetized cobalt fluidized bed catalyst for hydrogenation reaction of the present invention comprises using the magnetized cobalt fluidized bed catalyst for hydrogenation reaction of the present invention in a liquid phase hydrogenation reaction in a fluidized bed. After completion of the hydrogenation reaction, the catalyst is settled and separated in a liquid phase hydrogenation reaction system.

  The magnetized fluidized bed catalyst for hydrogenation reaction of the present invention has sufficiently high catalytic activity for liquid-phase hydrogenation reaction in practical use, and in the liquid-phase reaction, separation and recovery of the catalyst after completion of the reaction are easy, and Excellent practical use as a fluidized-bed catalyst for liquid-phase hydrogenation reaction, which can economically produce the target substance with high production efficiency because the catalyst has little decrease in the separability and activity even if it is reused repeatedly. Has a positive effect.

  Heretofore, there have been known examples in which a liquid-phase hydrogenation reaction was carried out in the presence of a magnetized cobalt fluidized bed catalyst for hydrogenation reaction, and examples in which the catalyst was sedimented and separated and then repeatedly used in a liquid-phase hydrogenation reaction. Absent. The present inventors have conducted intensive studies and found that, by applying a magnetic field having a magnetic flux density within a specific range to a particulate cobalt catalyst having a catalytic crystallite diameter of cobalt within a specific range. When the hydrogenated cobalt fluidized bed catalyst for hydrogenation reaction is used in a liquid phase reaction, the catalyst has excellent sedimentation properties, and can be easily separated, recovered and reused without special equipment, and the catalyst activity is practically sufficient. And found that the sedimentation was not significantly reduced even after repeated use, and completed the present invention.

  The cobalt fluidized bed catalyst in the present invention refers to a solid catalyst in which the shape is powder, fine particles, flakes, or the like, and the main catalytic action is exhibited by cobalt. Examples of the fluidized-bed cobalt catalyst include a sponge-free sponge-shaped cobalt-free sponge-cobalt catalyst and a cobalt-supported fluidized-bed catalyst in which cobalt having catalytic activity is supported on a porous carrier. The sponge cobalt catalyst is one of the following sponge metal catalysts.

The magnetized fluidized bed catalyst for hydrogenation reaction of the present invention is a fluidized bed catalyst for hydrogenation reaction comprising cobalt particles having a cobalt crystallite diameter in a crystal lattice plane (111) in a specific range in X-ray diffraction. It can be manufactured by applying a magnetic field having a magnetic flux density within a specific range to the cobalt particles to magnetize them.
In addition, examples of the cobalt particles for a fluidized bed catalyst to which a magnetic field is applied according to the present invention include the above-described sponge cobalt catalyst particles and cobalt-supported fluidized bed catalyst particles.

  The cobalt crystallite diameter at the crystal lattice plane (111) of the cobalt particles used in the present invention is 2.0 to 10.0 nm, and preferably 3.0 to 10.0 nm. When the cobalt crystallite diameter at the crystal lattice plane (111) is less than 2.0 nm, the effect of improving the sedimentation property of the obtained catalyst particles is insufficient, and when it exceeds 10.0 nm, the obtained catalyst particles This is not preferred because the catalytic activity of the compound greatly decreases.

  Cobalt fluidized bed catalyst particles having a crystallite diameter of 2.0 to 10.0 nm on the crystal lattice plane (111) are prepared by adding nickel fluidized bed catalyst particles having a crystallite diameter of less than 2.0 nm to water and / or organic fluid. It can also be produced by heating and stirring at 40 ° C. or higher in a solvent. If the heating and stirring temperature is lower than 40 ° C., the growth of the crystallite diameter is extremely slow, which is not practical.

The method of the present invention for producing sponge cobalt catalyst particles to which a magnetic field is to be applied will be described.
As a mother alloy used as a raw material of the sponge cobalt catalyst, a cobalt-aluminum alloy can be exemplified. The cobalt fluidized bed catalyst particles may be added as a salt with a secondary component metal for the purpose of improving the activity of the catalyst, the selectivity of the reaction or the durability of the catalyst.

A sponge cobalt catalyst having a cobalt crystallite diameter in the lattice plane (111) of 2.0 to 10.0 nm is produced by a method described in the aforementioned “Raney catalyst” (Kyoritsu Shuppan, 1971, Non-Patent Document 1) or the like. it can. An example is shown below.
A master alloy containing cobalt as an A metal having a catalytic action is added to an alkaline aqueous solution having a concentration of 5 to 50% by weight and having a concentration of 0.5 to 5 times the mass thereof, and developed at a temperature of 40 to 120 ° C. Thereafter, by washing with water, cobalt catalyst particles can be produced. The developing temperature and time for producing the sponge cobalt catalyst are preferably 0.5 to 2 hours at 40 to 100 ° C, more preferably 0.5 to 1 hour at 60 to 80 ° C. If the developing temperature is lower than 40 ° C., the growth of metal crystallites may be extremely slow. If it exceeds 100 ° C., the activity of the resulting catalyst may be insufficient.

  In addition, the crystallite size of cobalt of the sponge cobalt catalyst is affected by the ratio of cobalt to the other metal in the master alloy, and under the same development conditions, the lower the ratio of cobalt metal in the alloy, the smaller the crystallite size. Becomes larger.

The method of the present invention for producing cobalt-carrying fluidized bed catalyst particles to which a magnetic field is to be applied will be described.
Diatomaceous earth, pumice, acid clay, alumina, silica and the like can be used as a carrier for supporting cobalt.

The magnetic flux density of the applied magnetic field is 0.1 × 10 ^{−4 to} 3.0 T, and preferably 0.1 × 10 ^{−1 to} 1.0 T. An electromagnet or a permanent magnet is used as a magnetic field applying device. Preferably, an electromagnet is used. The current flowing through the electromagnet may be DC or AC. There is no particular limitation on the method of applying the magnetic field, but the cobalt crystallite diameter at the crystal lattice plane (111) is 2.0 to 10.0 nm, preferably 3.0 to 10.0 nm. Dispersed in water or in a liquid phase reaction mixture, and when transferred into a reactor through a pipe by a pump, a magnetic field is formed in the pipe in advance, and the catalyst particles passing through the pipe are magnetized. Preferably, a method is used. Further, the cobalt fluidized bed catalyst to which a magnetic field is applied may be a catalyst recovered after use in a liquid phase hydrogenation reaction.

  The chemical reaction in which the magnetized cobalt fluidized bed catalyst for hydrogenation reaction of the present invention is used is a liquid phase hydrogenation reaction, for example, hydrogenation of olefins, hydrogenation of aromatic compounds, carbonyl compounds such as aldehydes and ketones. Of oximes, imines, nitriles and nitro compounds to amines, reductive amination of carbonyl compounds to amines, hydrogenolysis of halogenated hydrocarbons, hydrogenolysis of benzyl compounds, sulfur compounds It is used for liquid phase hydrogenation such as desulfurization. Specific preferred reactions include hydrogenation of sugars such as glucose; hydrogenation of oils and fats (curing, partial curing); and deodorization, decolorization, and improvement of stability of higher fatty acids, higher fatty acid esters and higher alcohols. A liquid phase reaction such as a hydrogenation reaction may be mentioned. Further, since the magnetized hydrogenated cobalt fluidized bed catalyst for hydrogenation reaction of the present invention rapidly flocculates and sediments after its use and can be easily separated and recovered, when the viscosity of the liquid phase from which the catalyst is to be separated and removed is high, And when the catalyst is repeatedly used.

EXAMPLES The following examples illustrate the magnetized magnetic metal fluidized bed catalysts of the present invention and methods of using the same.

(1) The crystallite size at the crystal lattice plane (111) was calculated by the X-ray diffraction method. The measurement conditions of X-ray diffraction were as follows.
X-ray: Cu K _α1 / 40 KV / 40 mA
Counter: Scintillation counter Goniometer: RINT2000 vertical goniometer Attachment: Standard sample holder Filter: None Counter monochromator: Fully automatic monochromator Divergence slit: 1 deg.
Scattering slit: 1 deg.
Light receiving slit: 0.15mm
Scanning mode: continuous Scanning speed: 2.000 ° / min
Scan step: 0.010 ° / min
Scanning axis: 2θ / θ
θ offset: 0.000 °
Fixed angle: 0.000 °
Wavelength: 1.5405620
Apparatus constant: Cauchy function approximation Crystallite size: Cauchy function approximation K value list: 0.94 hkl half width width Surface index hkl: (111)
(2) The sedimentation of the cobalt fluidized bed catalyst for hydrogenation reaction after use in the liquid phase reaction was evaluated as follows. That is, after the completion of the reaction, the reaction solution was transferred to a 200-ml measuring cylinder, shaken up and down so that the catalyst was uniformly dispersed, allowed to stand for 30 minutes, and then the supernatant was removed. (Mass of precipitated and recovered catalyst) / (total mass of catalyst used for reaction) × 100 was calculated. The greater the sedimentation rate, the better the sedimentation of the catalyst.

Example 1 (Production of catalyst A)
50 g of cobalt-aluminum (Co: Al = 50: 50) alloy powder was charged into 300 g of a 25% aqueous sodium hydroxide solution, and the mixture was developed at 70 ° C. for 2 hours. 300 g of water was added to the developing solution, the mixture was stirred for 10 minutes, and then allowed to stand for 5 minutes to settle the catalyst particles, and the operation of removing the supernatant by decantation was performed as one cycle. Repeated times. As a result of analyzing the obtained sponge cobalt catalyst particles, the Co content was 95.5%, the Al content was 4.5%, the average particle diameter was 30 μm, and the cobalt crystallite diameter at the crystallite lattice plane (111) was 3.8 nm. Met. A magnetized sponge cobalt catalyst A was produced by applying a magnetic field having a magnetic flux density of 0.15 T to the obtained sponge cobalt catalyst particles.

Comparative Example 1 (Production of catalyst B)
Except that no magnetic field was applied, the same treatment as in Example 1 was carried out to obtain a Co content of 92.3%, an Al content of 7.7%, an average particle diameter of 20 μm, and a cobalt in the crystallite lattice plane (111). Unmagnetized sponge cobalt catalyst B having a crystallite diameter of 3.7 nm was produced.

Example 2 (use of catalyst A)
A magnetized sponge cobalt catalyst A (1.2 g), benzyl cyanide (175 g), methanol (32 g), and ammonia water (28%) (28.7 g) were charged into a 500 ml electromagnetically stirred autoclave, and the air in the autoclave was sufficiently replaced with hydrogen. The hydrogen pressure of the reaction system was increased to 6 MPa, and heated to a temperature of 140 ° C. to perform a hydrogenation reaction. Hydrogen absorption was completed in 1.5 hours. The sedimentation rate of the catalyst was 99%.

Comparative Example 2
A benzyl cyanide hydrogenation reaction was carried out in the same manner as in Example 2 except that the catalyst was changed to sponge cobalt catalyst B. Hydrogen absorption was completed in 1.6 hours. The settling rate of the catalyst was 40%.

  Table 1 shows the columnar shape of the catalyst used in the hydrogenation of benzyl cyanide in Example 2 and Comparative Example 2, the settling rate of the catalyst particles after use, and the time required for completing the reaction.

  The magnetized fluidized bed catalyst for hydrogenation reaction of the present invention has a sufficiently high catalytic activity for liquid-phase hydrogenation reaction in practical use, and in the liquid-phase reaction, separation and recovery of the catalyst after completion of the reaction are easy, and Even if this is repeatedly reused, the decrease in the separability and activity of the catalyst is small, so that it is suitable as a fluidized bed catalyst for a liquid phase hydrogenation reaction for the purpose of economically producing the target substance with high production efficiency.

Claims (4)

A magnetic field comprising a cobalt particle having a cobalt crystallite diameter of 2.0 to 10.0 nm on a crystal lattice plane (111) measured by an X-ray diffraction method and having a magnetic flux density of 0.1 × 10 ^{−4 to} 30 T A magnetized cobalt fluidized bed catalyst for hydrogenation reaction, comprising magnetic cobalt particles magnetized by application of voltage.   The magnetized cobalt fluidized bed catalyst for hydrogenation reaction according to claim 1, wherein the cobalt crystallite diameter at the crystal lattice plane (111) of the cobalt particles is 3.0 to 10.0 nm.   The magnetized cobalt fluidized bed catalyst for hydrogenation reaction according to claim 1, wherein the cobalt particles have a sponge-like morphology.   Using the magnetized cobalt fluidized bed catalyst for hydrogenation reaction according to any one of claims 1 to 3 in a liquid phase hydrogenation reaction in a fluidized bed, and after completion of the liquid phase hydrogenation reaction, using the catalyst, A method for using a magnetized cobalt fluidized bed catalyst for hydrogenation reaction, comprising sedimentation and separation in a liquid phase reaction system.