JP4174654B2 - Method for producing organohalosilane - Google Patents

Description

【００４８】
【発明の効果】
本発明の有機ハロシランの製造方法によれば、より少ない添加量のセシウム含有化合物でジオルガノジハロシランの選択率を向上させることができる。
【図面の簡単な説明】
【図１】メカノフュージョン装置の説明図である。
【符号の説明】
１ ケーシング
２ インナーピース
３ スクレーバー[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an industrial process for producing organohalosilanes.
[0002]
[Prior art and problems to be solved by the invention]
Regarding the method for synthesizing organic halosilanes, see US Pat. No. 2,380,995. Since Rochow disclosed the direct method of metal silicon and alkyl halides using copper catalysts, there are many related to various promoters used in the presence of copper catalysts, reactors, additives related to the reaction, etc. Researchers have reported improved results. In the industrial synthesis of organohalosilanes, the selectivity of diorganodihalosilanes most frequently used in silicone resins, the rate of silane formation, and the high conversion rate of metallic silicon to effective silanes are important.
[0003]
The selectivity of diorganodihalosilane is evaluated by the weight ratio (or molar ratio) in the produced silane and the T / D ratio.
[0004]
Examples of substances contained in the generated organic halosilane include diorganodihalosilane (D), triorganohalosilane (M), organotrihalosilane (T), and the like, and organohydrodihalosilane (H) and organohalodisilane. Also produces. In particular, in a silicone manufacturer using organic halosilanes as a raw material by this direct method, disilanes called high fractions are hardly induced to effective products, and most are discarded as residues.
[0005]
The T / D ratio is a composition ratio of organotrihalosilane and diorganodihalosilane in the total generated organic halosilane, and the smaller the T / D ratio, the better. On the other hand, the STY (Space Time Yield) value is used for the formation rate of the organic halosilane. The STY value is the weight of the produced crude organohalosilane per unit time relative to the weight of metal silicon held in the reactor. In order to improve the composition of these produced diorganohalosilanes, or to lower the T / D ratio and improve the STY value, various studies have been conducted focusing on catalysts and promoters.
[0006]
Japanese Patent Publication No. 63-43400 discloses a copper catalyst containing 0.05 to 4% cesium and 30 to 1000 ppm tin based on the total weight of silicon and the catalyst in order to increase the selectivity of dimethyldichlorosilane. A process for producing dimethyldichlorosilane in the presence is disclosed and reported to improve the selectivity of dimethyldichlorosilane. However, there is a problem that the cesium-containing compound is expensive.
[0007]
The present invention has been made in view of the above circumstances, and in the industrial production of organohalosilanes, the composition of the produced diorganodihalosilane is improved, the formation rate of organohalosilane is improved, and the conversion rate of metallic silicon to effective silane An object of the present invention is to provide a method for producing an organohalosilane that realizes the above at a lower cost.
[0008]
Means for Solving the Problem and Embodiment of the Invention
As a result of intensive studies to achieve the above object, the present inventor has made the cesium-containing compound finer and highly dispersed in the contact body, so that even if the amount of the cesium-containing compound that is an expensive promoter is small, The present inventors have found that the selectivity of diorganodihalosilane is improved, and have made the present invention.
[0009]
Specifically, cesium chloride used in Japanese Patent Publication No. 63-43400 as a cesium-containing compound has a melting point of 642 ° C., and at a normal reaction temperature in a reaction for producing an organic halosilane from metal silicon and an organic halide, Because it does not melt easily or has deliquescence, it easily aggregates into a large mass depending on the storage state. Therefore, it is considered that the cesium promoter in the reactor does not act effectively, and the effect will not appear unless it is added excessively. Therefore, the present inventor considered that if the cesium-containing compound was further refined and highly dispersed, the selectivity of the diorganodihalosilane was improved with a small amount of addition, and the present invention was achieved. According to the method of the present invention, the selectivity of diorganodihalosilane can be improved with a smaller amount of cesium-containing compound.
[0010]
Therefore, in the present invention, a reactor containing metal silicon, a copper catalyst and a cesium-containing compound having a cesium content of 50 to 10000 ppm relative to the weight of metal silicon is introduced into the reactor, and a gas containing an organohalide is introduced and reacted. Let the following general formula (1)
R _n (H) _m SiX _(4-nm) (1)
(In the formula, R represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, X represents a halogen atom, and n and m are integers satisfying 0 to 3 and n + m = 1 to 3).
In the method for producing an organic halosilane represented by the above, the contact body contains a product obtained by applying a shearing force to the mixture of the cesium-containing compound and the metal silicon powder. A method for producing an organohalosilane is provided.
[0011]
Hereinafter, the present invention will be described in detail.
The organohalosilane obtained by the method for producing an organohalosilane of the present invention is an organohalosilane represented by the general formula (1). In this case, in the general formula (1), R is a monovalent hydrocarbon group having 1 to 6 carbon atoms, and examples thereof include an alkyl group, alkenyl group, and aryl group having 1 to 6 carbon atoms. Group, alkyl group such as propyl group, and phenyl group are particularly preferable. n and m are integers satisfying 0 to 3 and n + m = 1 to 3. Particularly, n is preferably 2, m is preferably 0, and n + m = 2 is preferable. Examples of the halogen atom for X include chlorine, bromine, and fluorine. Of these, chlorine is preferred.
[0012]
Here, it is preferable to use metal silicon having a purity of silicon of 97% by weight or more, particularly 98% by weight or more.
Metal silicon is preferably pulverized and used as a powder having an appropriate particle size. When a fluidized bed reactor or a stirred bed reactor is used as a reactor, the metal silicon powder has good fluidity. Therefore, the particle diameter of the metal silicon powder is preferably in the range of 5 to 150 μm as the particle diameter corresponding to 50% of the weight-based cumulative distribution curve by sieving.
[0013]
Copper catalysts include various forms such as copper powder, stamping copper, atomized copper and other simple copper (metal copper), cuprous oxide, cupric oxide, copper halides such as copper chloride, and copper acetate. Can be used. In addition, various promoters such as zinc, tin, antimony, arsenic, and phosphorus may be used as a co-catalyst. In this case, the promoter may be used in the form of an alloy with copper, and as an alloy with copper. Cu—Zn, Cu—Sn, Cu—Zn—Sn (or Sb, As, P) and the like. Further, in the form used alone, as a co-catalyst, specifically, zinc compounds such as metal zinc, zinc chloride, zinc oxide and zinc acetate, tin compounds such as metal tin, tin chloride and tin oxide, metal antimony, antimony chloride, Examples include antimony compounds such as antimony oxide, aluminum compounds such as metal aluminum, aluminum chloride, and aluminum oxide, and inorganic phosphorus compounds such as metal phosphorus, copper phosphide, phosphorus trichloride, and phosphorus oxide. Of these, zinc, tin, and phosphorus are preferable. These may be used alone or in combination of two or more.
[0014]
The copper catalyst and the cocatalyst are preferably used as powder, and the particle size of the metal silicon powder is preferably in the range of 5 to 150 μm as the particle size corresponding to 50% of the weight-based cumulative distribution curve by sieving. .
[0015]
The amount of the copper catalyst is preferably 0.1 to 10 parts, particularly 2 to 8 parts in terms of copper weight with respect to 100 parts of metal silicon powder (parts by weight). In addition, the amount of the cocatalyst is appropriately selected from known amounts according to the type, form, and the like. For example, the amount of zinc is 0.05 to 1 part per 100 parts of metal silicon powder, tin, The blending amount of antimony and arsenic is preferably 0.001 to 0.05 part, particularly preferably 0.005 to 0.01 part, in any one kind or in total with respect to 100 parts of metal silicon powder. In addition, in the case of a compound such as a zinc compound, it is preferable to add it so as to be the above amount in terms of each metal.
[0016]
On the other hand, as an organohalide for reacting with metal silicon to obtain an organic halosilane, an organic halosilane to be produced, that is, the following general formula (1)
R _n (H) _m SiX _(4-nm) (1)
(In the formula, R represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, X represents a halogen atom, and n and m are integers satisfying 0 to 3 and n + m = 1 to 3).
Specific examples include methyl chloride, ethyl chloride, propyl chloride, benzene chloride, methyl bromide, ethyl bromide, propyl bromide, and benzene bromide. can do. Of these, methyl chloride and benzene chloride are preferred, and the most industrially effective one is methyl chloride. Dimethyldichlorosilane produced using this is widely used as a raw material for many silicone resins. The organohalide is heated in advance and gasified, and then sent to the reactor. In this case, the organohalide gas may be sent alone, or the amount that the powder fluidizes together with the inert gas may be fed. The amount of gas fed in is appropriately determined from the diameter of the reactor used and the superficial velocity. The amount of organohalide used is preferably such that the superficial velocity of the gas is not less than the minimum fluidization rate and the powder does not scatter violently.
[0017]
Examples of the cesium-containing compound used in the present invention include cesium-containing compounds such as cesium chloride, cesium bromide, cesium iodide, cesium acetate, and cesium carbonate. Of these, cesium chloride is preferred.
[0018]
As for the usage-amount of a cesium containing compound, it is preferable that cesium content is 50-10000 ppm with respect to a metal silicon weight, especially 300-8000 ppm.
[0019]
The cesium-containing compound may be refined or dispersed in the contact body, but the preferred method is that the cesium-containing compound is used alone or a cesium-containing compound and a metal silicon powder, a copper catalyst powder, a promoter powder, Mechanofusion device, ball mill, stirring mill, planetary mill, high speed rotary pulverizer, jet pulverizer, shear mill, roller mill, or stamp mill for a mixture of one or more selected from the group consisting of active powders It can be mentioned that the product obtained by the treatment with is contained in the touch body. Into the above apparatus, a cesium-containing compound alone or a mixture of a cesium-containing compound and one of a metal silicon powder, a copper catalyst powder, a promoter powder, an inert powder, or a plurality of powders By using the above apparatus, the cesium-containing compound can be finely dispersed in the contact body. In this case, it is preferable to treat the cesium-containing compound and the metal silicon powder, the copper catalyst powder, the promoter powder, and the inert powder together with at least one kind of powder. The cesium-containing compound obtained by the treatment or a mixture of the cesium-containing compound and metal silicon powder is preferably in the range of 5 to 150 μm as a particle size corresponding to 50% of the weight-based cumulative distribution curve by sieving.
[0020]
Here, the inert powder is not particularly limited as long as it is a powder that does not participate in the reaction in the so-called Rochow reaction in which an organic halosilane is produced from an organic halosilane and metal silicon. For example, silica, alumina, or the like is used. Can do. The particle diameter of these inert powders is preferably in the range of 5 to 150 μm as the particle diameter corresponding to 50% of the weight-based cumulative distribution curve by sieving, like the metal silicon powder.
[0021]
For example, as shown in FIG. 1, the mechano-fusion device (AM-15F) is charged with a raw material into the casing 1, rotated the casing 1, and pressed the raw material against the inner peripheral wall of the casing 1 by centrifugal force, and the inner piece A shearing force is applied between 2 and the casing 1 to highly disperse the cesium-containing compound on the surfaces of the metal silicon powder, the copper catalyst powder, the promoter powder, and the inert powder. The raw material modified between the inner peripheral wall of the casing 1 and the inner piece 2 is scraped off by a scraper 3 fixed to the rear of the inner piece 2 and the process of applying the shearing force is repeated again. The casing 1 is cooled to avoid abnormal temperature rise due to frictional heat. In other words, the mechano-fusion can give the powder particles compression, shearing, and introductory action by the rotating casing 1 and the fixed inner piece 2. The scraper 3 is for scraping off the powder compressed between the inner piece 2 and the casing 1 from the casing 1. This apparatus can apply mechanical energy to a single or a plurality of material particles to perform (1) surface fusion, (2) dispersion / mixing, and (3) particle size control.
[0022]
In actual operation, the motor power and the temperature of the powder particles at the inner piece part are measured and used as a guide for operation.
[0023]
Here, the rotational speed of the casing 1 and the clearance S between the casing 1 and the inner piece 2 are appropriately selected according to the apparatus to be used. In the case of the AM-15F mechanofusion apparatus, the rotational speed is 300. It is preferably ˜3000 rpm, particularly preferably 800 to 2200 rpm, and the clearance is preferably 0.1 to 10 mm, particularly preferably 0.5 to 5 mm.
[0024]
The treatment is preferably performed in a non-oxidizing atmosphere. As the non-oxidizing atmosphere, nitrogen gas, argon gas, hydrogen gas, or a mixed gas thereof can be used.
[0025]
An appropriate blending amount of the metal silicon powder and / or inert powder and the cesium-containing compound is preferably 1000: 1 to 10: 1 by weight, and more preferably 1000: 3 to 100: 1.
[0026]
Next, as a preferred method for making the cesium-containing compound fine and highly dispersed in the contact body, one or more selected from the group consisting of metal silicon powder, copper catalyst powder, promoter powder, and inert powder The powder is dispersed in a cesium-containing compound solution or sprayed with the cesium-containing compound solution and then dried in a non-oxidizing atmosphere, and the obtained product is contained in a contact body. Can be mentioned.
[0027]
Here, water is preferable as the solvent in the cesium-containing compound solution. As the non-oxidizing atmosphere, nitrogen, argon, hydrogen, or a mixed gas thereof can be used.
The treatment amount of cesium with respect to the cesium-supported metal silicon powder obtained by this method is preferably 1000: 1 to 10: 1, and more preferably 1000: 3 to 100: 1. Although the addition of a cesium-containing compound can be highly dispersed by carrying out in the form of a fine powder, the fine powder is scattered outside the system accompanying the introduced gas flow during the reaction, or in the air during storage. May solidify on contact with moisture.
[0028]
The method for producing an organohalosilane according to the present invention is a method in which a contact body containing metallic silicon, a copper catalyst and a cocatalyst is charged in a reactor, and a cesium-containing compound refined and highly dispersed in the contact body is used. Is introduced and reacted.
[0029]
In the method for producing the organohalosilane of the present invention, examples of the inert gas used for fluidizing the contact body of the reactor in the heating process of the contact body or the catalyst activity imparting process to the contact body include nitrogen gas, helium gas, and argon gas. However, it is preferable to use nitrogen gas from the viewpoint of economy. The flow rate of the inert gas in these steps may be equal to or higher than the fluidization start speed of the contact body, but is preferably about 5 times the fluidization start speed. If the flow rate of the inert gas is lower than this range, it is difficult to uniformly fluidize the contact body. On the other hand, if the flow rate of the inert gas is higher than this range, the scattering of the metal silicon powder increases, Loss and heat loss may increase. Further, it is preferable to circulate and use an inert gas and an organohalide.
[0030]
After imparting catalyst activity to the contact body as described above, an organohalosilane can be obtained by introducing an organohalide into the reactor and reacting the organohalide and metal silicon with a gas-solid contact reaction.
[0031]
In the present invention, the reaction is preferably carried out in the temperature range of 230 to 600 ° C, particularly 250 to 500 ° C. As the reactor, a fluidized bed reactor, a stirred bed reactor, a fixed bed reactor or the like can be used, and a continuous fluidized bed reactor is preferred industrially.
[0032]
【Example】
EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. In addition, the part in the following example shows a weight part.
[0033]
[Example 1]
Cesium chloride and metal silicon powder with an average of 70 μm were mixed at a weight ratio of 3: 1000 , using a “Mechanofusion” device (AM-15F) manufactured by Hosokawa Micron Corporation, stirring power of 1.0 kW, casing rotational speed of 1 The treatment was performed under a nitrogen stream under the condition of 200 rpm.
Next, 90 parts of an average 70 μm metal silicon powder, 10 parts of the cesium-treated metal silicon powder obtained above, and 5 parts of a catalyst mixture made of copper oxide were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm. The reaction was carried out at the reaction temperatures shown in Table 1. The reaction rate and effective silane composition (%) are shown in Table 1.
Reaction time: 6 hours Reactor internal pressure: 1.2 kg / cm ²
Gas flow rate: 1.0 NL / min
[0034]
[Example 2]
Cesium chloride and metal silicon powder with an average of 70 μm were mixed at a weight ratio of 1: 500 , using a “Mechanofusion” device (AM-15F) manufactured by Hosokawa Micron Corporation, stirring power 1.0 kW, casing rotational speed 1 The treatment was performed under a nitrogen stream under the condition of 200 rpm.
Next, 50 parts of an average 70 μm metal silicon powder, 50 parts of the cesium-treated metal silicon powder obtained above, and 4 parts of a catalyst mixture made of metal copper were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm. The reaction was carried out under the same conditions as in 1 and the reaction temperatures shown in Table 1. The reaction rate and effective silane composition (%) are shown in Table 1.
[0035]
[Example 3]
Cesium chloride and metal silicon powder with an average of 70 μm were mixed at a weight ratio of 1: 500 , using a “Mechanofusion” device (AM-15F) manufactured by Hosokawa Micron Corporation, stirring power 1.0 kW, casing rotational speed 1 The treatment was performed under a nitrogen stream under the condition of 200 rpm.
Next, 50 parts of an average 70 μm metal silicon powder, 50 parts of the cesium-treated metal silicon powder obtained above, and 5 parts of a catalyst mixture made of copper oxide were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm. The reaction was carried out under the same conditions as in 1 and the reaction temperatures shown in Table 1. The reaction rate and effective silane composition (%) are shown in Table 1.
[0036]
[Example 4]
Cesium chloride and metal silicon powder with an average of 70 μm were mixed at a weight ratio of 3: 1000 , using a “Mechanofusion” device (AM-15F) manufactured by Hosokawa Micron Corporation, stirring power of 1.0 kW, casing rotational speed of 1 The treatment was performed under a nitrogen stream under the condition of 200 rpm.
Next, 100 parts of the cesium-treated silica powder obtained above and 5 parts of a catalyst mixture made of copper oxide were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm. The same conditions as in Example 1 and Table 1 are shown. The reaction was carried out at the reaction temperature. The reaction rate and effective silane composition (%) are shown in Table 1.
[0037]
[Example 5]
Cesium chloride and silica powder with an average of 70 μm were mixed at a weight ratio of 1: 100 , and using a “Mechanofusion” device (AM-15F) manufactured by Hosokawa Micron Corporation, stirring power 1.0 kW, casing rotational speed 1, The treatment was performed under a nitrogen stream at 200 rpm.
Next, 100 parts of an average 70 μm metal silicon powder, 10 parts of the cesium-treated silica powder obtained above, and 5 parts of a catalyst mixture made of copper oxide were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm. The reaction was carried out under the same conditions as in Table 1, and the reaction temperatures shown in Table 1. The reaction rate and effective silane composition (%) are shown in Table 1.
[0038]
[Example 6]
Cesium chloride and metal silicon powder with an average of 100 μm were mixed at a weight ratio of 1: 500 , using a “Mechanofusion” device (AM-15F) manufactured by Hosokawa Micron Corporation, stirring power of 1.0 kW, casing rotational speed of 1 The treatment was performed under a nitrogen stream under the condition of 200 rpm.
Next, 50 parts of an average 70 μm metal silicon powder, 50 parts of the cesium-treated metal silicon powder obtained above, and 4 parts of a catalyst mixture made of metal copper were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm. The reaction was carried out under the same conditions as in 1 and the reaction temperatures shown in Table 1. The reaction rate and effective silane composition (%) are shown in Table 1.
[0043]
[Comparative Example 1]
100 parts of metal silicon powder with an average of 70 μm and 5 parts of a catalyst mixture made of copper oxide were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm, and reacted under the same conditions as in Example 1 and the reaction temperatures shown in Table 1. Went. The reaction rate and effective silane composition (%) are shown in Table 1.
[0044]
[Comparative Example 2]
100 parts of metal silicon powder having an average of 70 μm, 5 parts of a catalyst mixture made of copper oxide, 0.03 part of cesium chloride were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm. The same conditions as in Example 1 and Table 1 The reaction was carried out at the reaction temperature indicated in. The reaction rate and effective silane composition (%) are shown in Table 1.
[0045]
[Comparative Example 3]
100 parts of metal silicon powder having an average of 70 μm, 5 parts of a catalyst mixture made of copper oxide, 0.1 part of cesium chloride were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm. The same conditions as in Example 1 and Table 1 The reaction was carried out at the reaction temperature indicated in. The reaction rate and effective silane composition (%) are shown in Table 1.
[0046]
[Comparative Example 4]
100 parts of metal silicon powder having an average of 70 μm, 5 parts of a catalyst mixture made of metallic copper, 0.3 part of cesium chloride were passed through methyl chloride in a reactor having an inner diameter of 50 mm and a height of 500 mm, the same conditions as in Example 1, and Table 1 The reaction was carried out at the reaction temperature indicated in. The reaction rate and effective silane composition (%) are shown in Table 1.
[0047]
[Table 1]

[0048]
【The invention's effect】
According to the method for producing an organohalosilane of the present invention, the selectivity of diorganodihalosilane can be improved with a smaller amount of cesium-containing compound.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a mechanofusion device.
[Explanation of symbols]
1 Casing 2 Inner piece 3 Scraper

Claims (3)

A reactor containing metal silicon, a copper catalyst, and a cesium-containing compound having a cesium content of 50 to 10000 ppm relative to the weight of the metal silicon is introduced into the reactor, and a gas containing an organohalide is introduced and reacted. (1)
R _n (H) _m SiX _(4-nm) (1)
(In the formula, R represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, X represents a halogen atom, and n and m are integers satisfying 0 to 3 and n + m = 1 to 3).
In the method for producing an organic halosilane represented by the above, the contact body contains a product obtained by applying a shearing force to the mixture of the cesium-containing compound and the metal silicon powder. A method for producing an organic halosilane. Shear mechanofusion device, ball mill, stirring mill, planetary mill, high-speed rotary grinder, jet mill, shearing mill, organic according to claim 1, characterized in that imparted by treatment with a roller mill, or stamp mill A method for producing halosilane. The process according to claim 1 or 2 , wherein the reaction temperature is 230 to 600 ° C.

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