JPS6246914A - Disproportionation method for silanes - Google Patents

Abstract

PURPOSE:To produce silanes different from starting materials efficiently by bringing silanes having a specified structure into contact with a metallic sulfate on a carbonaceous substance as a carrier to cause disproportionation. CONSTITUTION:Silanes represented by the general formula (where n=1-4, R is H or a hydrocarbon group and X is halogen or alkoxy), e.g., halogenated silanes, alkylsilanes or arylsilanes are used as starting materials. The silanes are brought into contact with a catalyst consisting of a metallic sulfate such as sodium sulfate and a carbonaceous substance such as activated carbon as a carrier to cause disproportionation. The preferred disproportionation temp. is 0-800 deg.C. By this method, chlorine- or hydrogen-rich silanes different from the silanes as the starting materials are obtd. at a high rate of conversion.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to a method for producing a new silane compound by disproportionating silanes represented by the general formula Rn5iX4-n. A disproportionation reaction is caused by bringing the supported silanes into contact with silanes represented by the general formula Rn5ix4-n to produce silanes different from the raw material silanes, such as monosilane and dichlorosilane, at low cost and easily. Concerning a highly efficient manufacturing method.

[Background technology]

In recent years, with the development of the electronics industry, monosilane and chlorosilane have become particularly important as raw materials for producing polycrystalline silicon, single crystal silicon, amorphous silicon, etc.

That is, monosilane (SiH, ) is being used as a raw material for the above-mentioned high-purity silicon, a semiconductor raw material for solar cells, a raw material for silicon epitaxial films, etc., and demand is expected to increase significantly in the future. Therefore, a method for producing monosilane easily and efficiently at low cost is desired. On the other hand, chlorosilanes such as dichlorosilane are also expected to be in great demand as raw materials for manufacturing silicon for semiconductors. In addition, hydrocarbon-containing silanes such as alkylsilanes are expected to be in great demand in the future as raw materials for silicones, polycarposilanes, and the like.

Conventionally, the following methods are generally known as methods for producing monosilane (SiH).

(1) Method of reacting magnesium silicide (Mg25+) with hydrochloric acid; (2) Method of reacting magnesium silicide with ammonium chloride or ammonium bromide in liquid ammonia; (3) Silicon tetrachloride and lithium hydride in an ether solvent (4) A method of redistributing or disproportionating trichlorosilane using an anion exchange resin containing a tertiary amine group or a quaternary ammonium group as a catalyst; (5) A method of reacting aluminum with lithium chloride and potassium chloride. (6) A method in which lithium hydride and silicon tetrachloride are reacted in a molten salt; (6) A method in which hydrogen gas is reacted with metallic silicon in the presence of an N1 catalyst under high temperature and high pressure conditions; and the like.

However, in method (1), a higher silicon compound (SinH2n+2) (where n is 2) is used in addition to monosilane.
is an integer greater than or equal to ) as a by-product, and the yield of monosilane is also low. Furthermore, since Mg is expensive, it is not economical. (
Method 2) provides a high yield of monosilane, but the reaction steps such as separation of ammonia are complicated, and Mg is expensive, making it uneconomical. In method (3), highly pure mono7rane can be obtained in high yield, but it is difficult to industrialize because the lithium aluminum hydride used as the reducing agent is expensive and there are also problems in continuous process. I'll go. In method (5), the by-product lithium chloride is electrolyzed to produce metallic lithium, which is hydrogenated and returned to lithium hydride, making it possible to use it as a recycling system, making it an inexpensive method for producing monosilane, but it is corrosive. It is large and has problems such as corrosion of the equipment, so it has not yet been put into practical use. Method (6) involves high temperature, high pressure reaction, and therefore costs such as setup and cleaning costs are high, and in addition, the high temperature causes decomposition of the product, making it impractical.

However, method (4) is a catalytic reaction, and in addition, it is possible to hydrogenate silicon tetrachloride produced as a by-product and reuse it as trichlorosilane, and it does not require extremely high temperature and pressure, so it is energy efficient. It is also advantageous, the equipment is simple, and the method is highly economical. This silane production method requires a chlorosilane disproportionation catalyst, and homogeneous liquid phase, gas-solid or liquid-solid phase heterogeneous catalysts are known. In other words, as a liquid phase homogeneous catalyst, 6th class amine, α
- Oquinamine and the like are known, but this method is not suitable for mass production by continuous flow reaction. In addition, in gas-solid or liquid-solid heterogeneous reactions using solid catalysts, 3
Ion exchange resin catalysts of the class amine or quaternary ammonium salt type are known and are suitable for producing large amounts of monosilane by continuous flow reaction. However, these catalysts have low thermal stability, and catalyst deterioration is easily observed during long-term reactions.
In addition, in practice it is not possible to carry out high temperature reactions, which are known to favor products in disproportionation reactions. Further, catalyst regeneration is difficult, and the ion exchange resin is expensive, which has a large impact on economic efficiency.

On the other hand, the method (4) above is known as a method for producing dichlorosilane, and the problems associated with this production include the same problems as those for monosilane. Note that there is another method for obtaining dichlorosilane as a by-product when producing trichlorosilane from metal silicon, but the yield is low and it is not practical.

Furthermore, in the disproportionation reaction of alkylsilanes, etc.,
Although the method according to 4) is known, it still has the above-mentioned drawbacks. In addition, other methods using aluminum halide as a catalyst are known, but when aluminum halide is used as a catalyst, the reaction is extremely slow, and the reaction rate is usually 300 to 60
Even at 0°C, only a low conversion rate is shown.

[Purpose of the invention]

Therefore, the object of the present invention is to produce monosilanes using halogenated silanes and hydrocarbon-containing silanes as raw materials, similar to the method (4) above, which uses trichlorosilane, etc. as the raw material, which is the most abundant source of silicon. It is an object of the present invention to provide a disproportionation method for producing silanes different from raw material silanes.

Another object of the present invention is to have extremely high thermal stability compared to conventionally known heterogeneous solid catalysts such as tertiary amine type or quaternary ammonium salt type anion exchange resins. It is possible to carry out reactions at high temperatures, which are advantageous for reaction equilibrium products (monosilane, monochlorosilane, dichlorosilane, and tetrachlorosilane), such as the disproportionation reaction of trichlorosilane, and it has a long life and is inexpensive. The object of the present invention is to provide a method for disproportionation that involves contacting with a catalyst that can be prepared very easily.

[Disclosure of the invention]

According to the present invention, silanes represented by the general formula % (where n is an integer from 1 to 4, and R is hydrogen or a hydrocarbon group, or a halogen atom or an alkoxy group) are used. The present invention will be described in detail below, providing a method for disproportionation of silanes, which is characterized by bringing the silanes into contact with a metal sulfate supported on a carbonaceous material.

The silanes used as raw materials in the present invention have the general formula % (4) (where n is an integer of 1 to 4, R is hydrogen or an alkyl group having 1 to 10 carbon atoms, A hydrocarbon group such as an allyl group having ~10 carbon atoms or an aryl group having 6 to 20 carbon atoms, where X is a halogen atom such as fluorine, chlorine, bromine, or iodine, or an alkoxy group such as methoxy or ethoxy). Examples include halogenated silanes, alkylsilanes, alkylhalogenated silanes, alkoxysilanes, alkoxyhalogenated silanes, alkylhalogenated alkoxysilanes, alkylalkoxysilanes, alkenylsilanes, alkylhalogenated silanes, arylsilanes, and arylno-halogenated silanes. These include silane, arylalkoxysilane, arylalkylsilane, alkylarylnorogenated silane, and arylhalogenated alkoxysilane.

Specifically, trichlorosilane, dichlorosilane, monochlorosilane, tribromosilane, sifuromosilane, monobromosilane, triiodosilane, shortsilane,
Monoiodosilane, trifluorosilane, difluorosilane, monofluorosilane, monomethylsilane, diethylsilane, monoethyl 7rane, methylchlorosilane, dimethylchlorosilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, monoethylsilane, diethylsilane, triethyl Silane, ethylchlorosilane, ethyldichlorosilane, ethyltrichlorosilane, diethylchlorosilane, diethyldichlorosilane, triethylchlorosilane, methylbromosilane,
Methylchlorosilane, methyltribromosilane, dimethylbromosilane, dimethyldibromosilane, trimethylbromosilane, ethylbromosilane, ethylchlorosilane, ethyltribromosilane, diethylbromosilane,
Diethyldibromosilane, triethylbromosilane, methylfluorosilane, methyldifluorosilane, methyltrifluorosilane, dimethylfluorosilane, trimethylfluorosilane, ethylfluorosilane, ethyldifluorosilane, ethyldifluorosilane, diethylfluorosilane, diethyldifluorosilane, triethyl Fluorosilane, methyliodosilane, methylshortsilane, methyltriiodosilane, trimethyliodosilane, ethyliodosilane, ethyltriiodosilane,
Phenylsilane, diphenylsilane, triphenylsilane, phenylchlorosilane, diphenylchlorosilane,
triphenylchlorosilane, diphenylchlorosilane,
Triphenylchlorosilane, phenylbromosilane, diphenylbromosilane, triphenylbromosilane, diphenyldibromosilane, triphenylbromosilane,
Phenylfluorosilane, diphenylfluorosilane,
Triphenylfluorosilane, diphenyldifluorosilane, triphenylfluorosilane, vinylsilane, divinylsilane, vinylchlorosilane, vinyltrichlorosilane, methoxysilane, dimethoxysilane, trimethoxysilane, ethoxysilane, jetoxysilane, triethoxysilane, chloromethoxysilane , dichloromethoxysilane, trichloromethoxysilane, methylmethoxysilane, methyldimethoxysilane, methyltriethoxysilane, chloroethoxysilane, dichloroethoxysilane, trichloroethoxysilane, chlorojethoxysilane, vinylmethoxysilane, divylmethoxysilane,
Halogen-containing and /or hydrocarbon-containing group and /'! or alkoxysilanes, and one or a mixture of two or more of these.

The present invention uses the above-mentioned silanes as a raw material, contacts them with metal sulfates supported on a carbonaceous material, and processes group I (alkali metals) excluding hydrogen in the long period periodic table on pages 1548 to 1549. and copper group), ■ group (alkaline earth metals and zinc group), ■ group excluding boron, ■ group excluding carbon and silicon, Rufu group (iron group and white metals) and ■, ■,
These are elements belonging to each subgroup a of group ①, antimony, bismuth, and boronium.

In addition, in the present invention, the metal sulfate supported on the carrier is (a) general formula Mx(so,)y (where M is the metal defined above (the same applies hereinafter), and when the valence of M is 2, the following Something that satisfies the relational expression and is expressed as Xz”2Y% (x, y, z are positive integers]); (b) General formula MX (ISO,) y (where M
is a metal, and when the valence of M is 2, x satisfies the following relational expression
z=y.

[x, y, z are positive integers]); (C)
General formula MxMy(so,)z (where M is a metal, and M is a metal or cationic substance different from M, such as N
H, etc., and when the valence of M is a, and the valence of M' is, a, b
, x, y, and z satisfy the following relational expression.

ax+by=2z, (a, b, x, yz are positive integers])
What is represented by the general formula MXM'Y (ISO,)
Z.

(However, M is a metal, zo is a metal or a cationic substance, and the valence of M is a, and the valence of M' is a.

b, x, y, and z satisfy the following relational expression. ax+by=z
(a, b, x, y, z are positive integers); (d) General formula MX MX MX MX
``n(804))'' (However, at least one of Ml,...1Mn is a metal and the others are cationic substances.The valence of Ml, M2...,M'' is a
If l, a2;...an, then al.

a2, −・−, an, Xi, X2, −・′, xn and y are an・Xi ...・xn+Y and n are positive integers] One is a metal and the other is a cationic substance.Also, M
l, M2゜...9The valence of Mn is al, a2,...
...+ ``If n, then al, a2. ・=・, an,
Xi, X2.・=・, Xn and "2 + ""+
“n r xlrx2+ ””+ Xn +Y and n
is a positive integer]); (e) General formula MX (S207) y (where l, M is a metal, and if the valence of M is Z, then x+lY+ z is the following relational expression x
z-2y (x, y, z are positive integers); (f) sulfates of halogen-containing, oxygen-containing and sulfur-containing atomic metals; and the like.

Specific examples of the sulfates represented by the above general formula include zinc sulfate, ammonium zinc sulfate, aluminum sulfate, ammonium sulfate (M), ammonium aluminum sulfate, and ammonium chromium sulfate (III).
), ytterbium sulfate (lll), thorium sulfate, indium sulfate (IN), uranyl sulfate, uranium sulfate (■), erbium sulfate (IID), potassium magnesium chloride sulfate, cadmium sulfate, gadolinium sulfate (l)
D, potassium sulfate, gallium sulfate (1), potassium aluminum sulfate, potassium chromium sulfate, calcium sulfate,
Gold sulfate, silver sulfate, guanium aluminum sulfate, chromium sulfate, cobalt sulfate, ammonium cobalt sulfate, potassium cobalt sulfate, samarium sulfate, dysprosium sulfate, zirconium sulfate, mercury sulfate, potassium hydrogen sulfate, cesium hydrogen sulfate, sodium hydrogen sulfate, Lithium hydrogen sulfate, scandium sulfate, tin sulfate, strontium sulfate, cesium sulfate, cesium aluminum sulfate, cerium sulfate, ceric ammonium sulfate, thallium sulfate,
Titanyl sulfate, titanium sulfate, iron sulfate, ammonium ferrous sulfate, terbium sulfate, copper sulfate, thorium sulfate, sodium sulfate, sodium aluminum sulfate, lead sulfate, nickel sulfate, disochel ammonium sulfate, neodymium sulfate,
Platinum sulfate, vanadium sulfate, vanadyl sulfate, palladium sulfate, barium sulfate, bismuth sulfate, fraseodymium sulfate, praseodymium sulfate, beryllium sulfate, holmium sulfate, magnesium sulfate, magnesium sulfate potassium, magnesium sulfate sodium, manganese sulfate, manganese ammonium sulfate, sulfuric acid Coulobium, lanthanum sulfate, lithium sulfate, lutetium sulfate, rubidium sulfate, rubidium aluminum sulfate, rhodium sulfate,
Examples include potassium rhodium sulfate, potassium pyrosulfate, and sodium pyrosulfate.

Further, even if a metal has a plurality of valences, the valences do not matter. Further, the sulfate salt may contain water of crystallization, but it is preferable to remove the water of crystallization and use it in the form of an anhydrous salt.

In the present invention, the carbonaceous material used as a support for supporting sulfate is an allotrope of carbon that does not show a clear crystalline state; or it has a crystal lattice similar to graphite, but this lattice is disordered. A collection of small crystals with an arrangement; or a material made of crystalline carbon such as graphite; specifically, a variety of materials such as wood, charcoal, fruit shells, peat, grass charcoal, lignite, lignite, coal, pitch, tar, etc. material.

activated carbons, acetylene black, carbon black, bone char, graphite, charcoal, etc.

Moreover, two or more types of carriers may be used as a mixture. The carrier and supported catalyst may be in any form, such as powder or granules. In particular, in the case of granules, it is also possible to use molded or crushed ones such as rods, rings, fibers, and mesh shapes. be.

In the present invention, the amount of metal sulfate supported on the carbonaceous material is 0.02% by weight to 1% by weight based on the weight of the carbonaceous material.
00 weight percent, preferably from 0.1 weight percent to more than 70 weight percent, and more preferably from 0.5 weight percent to 50 weight percent. Furthermore, when a metal sulfate is supported on a carbonaceous material, one or a mixture of two or more of the sulfates in the above group may be supported.

For example, the following preparation method can be employed to support the above metal sulfate on a carbonaceous material. Note that the present invention may be applied to any of these preparation methods, and is not limited to these preparation methods.

(1) Dissolve the metal sulfate salt in a solvent in a container, add a certain amount of carbonaceous material to it, and fully impregnate it, then remove the solvent at normal pressure or reduced pressure (by heating if necessary) Method of supporting by distillation and drying; (2) A certain amount of carbonaceous material is placed in a reaction tube in advance, and a metal sulfate solution is flowed into the reaction tube, brought into contact with the carrier, and adsorbed onto the carrier. , a method of supporting by distilling off the solvent and drying; (3) Dissolving the metal sulfate in a solvent in a container, adding a certain amount of carbonaceous material to it and thoroughly impregnating it;
A method of drying and supporting hypermobility; (4) After placing a carbonaceous material in a container in advance and reducing the pressure inside the container, a metal sulfate solution is injected, followed by filtration or distillation of the solvent, and then Method of supporting by drying; (5) Method of supporting by known means such as cross-wire method, spray method, etc.] It is also possible to use a supported catalyst that has been supported by these methods and then pulverized appropriately.

In the present invention, a disproportionation reaction is carried out using the metal sulfate supported on a carbonaceous material prepared as described above as a catalyst.

The disproportionation reaction referred to in the present invention refers to raw material silanes Rn5ix
From (4-n), more X-rich silanes and more R
is an equilibrium reaction in which silanes rich in silane are produced. For example, the raw material silane is trichlorosilane (R=H, X=t
) refers to each of the following reactions, and is a combination of these.

2SiHCt3 Se==;5iH2C! t2-1-8
iCt42SiH2Ct2===18 i H3C!
t+S i HCt32SiH31:! t Length===
q S i H,-)-S i H2CL2, i.e.
This is an equilibrium reaction in which more chlorine-rich silanes and more hydrogen-rich silanes are produced from the raw material chlorosilanes.

When the supported catalyst of the present invention is used, the disproportionation reaction rate itself is extremely fast and equilibrium is reached in a short time; however, considering the equilibrium composition, it is desirable that the temperature is as high as possible to maintain the stability of the catalyst. From this point of view, the reaction temperature for disproportionation (or redistribution) in the present invention is between 0 and 800°C, preferably between 50 and 300°C.

Next, a specific embodiment of bringing silanes into contact with a catalyst to carry out a disproportionation reaction will be described.

Basically, the reaction can be carried out by any method including normal pressure, increased pressure or reduced pressure reaction in gas phase-solid phase or liquid phase-solid phase. For example, the following reaction method can be adopted as a method that is easy to implement.

(1) A method in which the supported catalyst and raw material silanes are placed in a container and stirred and heated under normal pressure under reflux; (2) The supported catalyst and raw material silanes are placed in a pressure-resistant container and stirred and heated under pressure. (3) A method in which the catalyst is packed in a single tube and the raw material silanes are continuously flowed into the catalyst layer as a liquid or gas under pressure, normal pressure, or reduced pressure to carry out the reaction; To process a large amount of silanes Although method (3) is preferable, the present invention is of course not limited to these methods.

The raw material silanes used in this reaction and the product silanes such as monosilane and halogenated silane are active and easily decomposed by water, alcohol, aqueous alkaline solutions, and the like. Furthermore, some react violently with oxygen and ignite and decompose, so the reaction must be carried out in an atmosphere that is inert to the raw material silanes and the product silane.

For example, it is preferable to conduct the reaction after preparing the reaction system in advance in an atmosphere of an inert gas such as helium, argon, hydrogen, nitrogen, etc., which has been sufficiently dehydrated and deoxidized.

[Action by invention]

According to the present invention, in the conventional catalytic reaction method for disproportionating halogenated silanes, which has been an excellent method for producing monosilane, the catalyst itself is expensive, and deterioration due to thermal instability of the catalyst. Therefore, in the present invention, the metal sulfate supported on a carbonaceous material has the drawbacks such as not being able to perform a high temperature reaction that is advantageous for the product (that is, resulting in a high conversion rate of the raw material) in the disproportionation reaction. By using it as a disproportionation catalyst such as halogenated silane, it can prevent deterioration due to its thermal stability, which is a characteristic of sulfates.
In addition, we have made it possible to carry out the reaction at extremely high activity (through interaction with carbonaceous materials) at high temperatures where a challenging reaction conversion rate can be obtained. In addition, the catalyst of the present invention is extremely inexpensive compared to conventional anion exchange resin type disproportionation catalysts, and therefore has excellent advantages in the disproportionation method for producing the monosilane etc. Therefore, the economic effect brought about by this manufacturing method is enormous.

〔Example〕

The present invention will be explained in detail below using examples.

In addition, in the following Examples and Comparative Examples, when using gas phase silanes, the reactor outlet was heated to 70°C.
The produced gas was flowed into a constant temperature gas sampler for gas chromatography kept at ℃, and the composition was analyzed in gaseous form using a gas chromatograph. The analytical values were obtained after the reaction reached steady state, and it was confirmed that the time required for the reaction to reach steady state was within 1 hour.

Example 1 The sulfates of the metals shown in Table 1 were added to activated carbon (Shirasugi Lc''/32, manufactured by Takeda Pharmaceutical Co., Ltd.) as a blinding medium by the method described in (1) above. The supported catalyst was packed into a glass reaction tube with an inner diameter of 11 mm (50 mm) to a capacity of 50 mm (filling volume: 4.75 rr).
tl). Thereafter, the reaction tube was heated to 150° C. with oil gas, and trichlorosilane with a purity of 99.9% was supplied at an inflow rate of 25 y/hr. The results are shown in Table 1.

As shown in the results in Table 1 above, disproportionation reaction activity was observed for various metal sulfates supported on activated carbon, and most of them reached 9-reaction equilibrium at 150°C within a few seconds of contact time. I understand.

Example 2 Potassium sulfate and sodium sulfate were mixed with activated carbon (white cedar L)
Using CB152 (manufactured by Takeda Pharmaceutical) as a catalyst supported at 3% by weight based on the weight of activated carbon, a non-uniform reaction was carried out by using the same reaction apparatus, the same catalyst, and the loading amount as in Example 1, but changing the reaction temperature and the inflow rate of trichlorosilane. A chemical reaction was carried out. The results were as shown in Table 2. Some of the results of Example 1 are also shown.

As shown in Table 2 above, no deterioration was observed even when the reaction was carried out at high temperatures, and equilibrium was reached within a very short contact time of several seconds, indicating that it is a highly active catalyst for the reaction. Ta.

Example 6 The same reaction apparatus as in Example 1 was used at 100°C with the loading ratio of potassium sulfate on activated carbon (White Sugi LC8/32) at 50, 10, 6, and 0.5 weight percent (based on activated carbon weight).
The disproportionation reaction was carried out with the same trichlorosilane inflow rate (25 y/hr) and the same catalyst loading. As shown in Table 3, the results showed high disproportionation catalyst activity over a wide range of supported amounts. A part of the results of Example 2 are also shown.

Table 3 Example 4 Potassium sulfate was mixed with activated carbon SGI, 8/30 (Toyo Calgon Co., Ltd., Coal Charcoal), carbon blank: Continex T (Mitsui Toatsu Chemical Co., Ltd.), Carbon Black Niketschen Blank GC (Lion Akzo Co., Ltd.) Using the same reactor as in Example 1 and the same catalyst loading amount, the inflow rate of trichlorosilane was 25 V'hr, And the disproportionation reaction was carried out at a reaction temperature of 150°C. As shown in Table 4, the results showed that the catalysts supported on each carbonaceous material exhibited excellent reaction activity.

Table 4 Comparative Example 1 Inflow rate of trichlorosilane was 25 y/hr using the same reactor and the same catalyst loading amount as in Example 1, using potassium sulfate supported on γ-alumina and titania at 6 weight percent each as a catalyst. The disproportionation reaction was carried out at 150°C. As a result, no matter which catalyst was used, almost no disproportionation was observed and only the raw material trichlorosilane was recovered.

Comparative Example 2 Potassium sulfate and activated carbon (white cedar LC8/32) were separately put into the same reactor as in Example 1 in the same amount as the catalyst loading amount in Example 1 at 150°C and trichlorosilane inflow rate of 25 y/ Each disproportionation reaction was carried out for hr. As a result, when only potassium sulfate was charged, almost no disproportionation activity was observed and only the raw material was recovered. Further, when only activated carbon was charged, the initial conversion rate of trichlorosilane was 8%, but the activity completely disappeared after 30 minutes.

It is clear from the results of Comparative Examples 1 and 2 above that in the disproportionation reaction, by using the metal sulfate and the carbonaceous substance in combination in the form of supporting the metal sulfate on the carbonaceous substance, It was revealed for the first time that catalytic activity was exhibited.

Example 5 20 y of dichlorosilane was used in the same reactor and the same catalyst loading as in Example 1, using 3% by weight (based on activated carbon weight) of potassium sulfate supported on activated carbon (White Sugi LC8/32) as a catalyst. The disproportionation reaction was carried out at a feed rate of /hr. As shown in Table 5, the disproportionation reaction proceeded at an extremely high conversion rate within a few seconds of contact time.

Table 5 Example 6 Using the catalyst of Example 5, the same reactor and the same catalyst loading as Example 1, the inflow rate of trichlorosilane was 2.
Trichlorosilane was disproportioned at a disproportionation temperature of 150° C. for 5 y/hr. The results of analyzing the product 1 hour and 40 hours after the start of the reaction are shown in Table 6.
Even after 0 hours, no decrease in catalyst activity was observed and the disproportionation reaction equilibrium composition was maintained.

Table 6 Comparative Example 3 Using the same equipment as in Example 1, Amberlis (manufactured by Rohm and Haas), which is a tertiary amine type anion exchange resin, was used.
-21 was subjected to a disproportionation reaction at the same TFI amount as in Example 1, an inflow rate of 25 y/hr of trichlorosilane, and 120'C, and the products were analyzed after 1 hour and 40 hours. The results are shown in Table 7. In Example 6, no decrease in activity was observed even after 40 hours at 150°C, but a significant decrease in activity was observed even at 120°C, indicating that the catalyst had deteriorated. Ta.

Table 7: Add 3% by weight of luamine to activated carbon (white cedar LC8/
32 A disproportionation reaction was carried out using the same Catalyst Light JJ111 as in Example 1 at an inflow rate of 25 g/hr of trichlorosilane and 120°C in the same manner as in Comparative Example 1. The results of analysis of the product after 40 hours and after 40 hours showed that the initial activity was lower than that of the catalyst of the present invention carried out at 100°C (Example 2, Table 2) and after 40 hours, as shown in Table 8. A significant decrease in activity was also observed.

Table 8 Example 7 A 100 d autoclave was charged with the same catalyst 5°Of as in Example 6 and methyldichlorosilane ((!H,S i 暎)402, and the reaction mixture was reacted for 2 hours with stirring at 150°C. The reaction solution was analyzed by gas chromatography.The composition of the reaction solution was as follows, indicating extremely high disproportionation catalytic activity.

Example 8 The same catalyst 5 as in Example 6 was placed in a 100 m/autoclave.
．． 0? , methyldichlorosilane (0H3SiHC4)2
0.1y and trichlorosilane (5iH(!t3)
13.72 was charged (preparation composition: 65.4% methyldichlorosilane, 366% trichlorosilane) and reacted for 2 hours with stirring at 150°C, and then analyzed the composition.

The results showed extremely high disproportionation activity as shown below.

Claims (4)

[Claims] (1) Silanes represented by the general formula R_nSiX_(_4_-_n_) (where n is an integer from 1 to 4, R is hydrogen or a hydrocarbon group, and X is a halogen atom or an alkoxy group) 1. A method for disproportionating silanes, which comprises bringing silanes into contact with a metal sulfate supported on a carbonaceous material. (2) The method according to claim 1, wherein the carbonaceous material is selected from activated carbons, carbon black, acetylene black, or graphite. (3) The method according to claim 1, wherein the disproportionation reaction is carried out at a temperature of 0 to 800°C. (4) The method according to claim 1, wherein the disproportionation reaction is carried out at a temperature of 50 to 300°C.