JPWO2011132621A1 - Catalyst for disproportionation reaction of hydrohalogenated silane and method for producing monosilane using the same - Google Patents

Abstract

An object of the present invention is to provide a liquid catalyst for the disproportionation reaction of a hydrogenated halogenated silane with high production efficiency of monosilane. There is provided a liquid catalyst for the disproportionation reaction of a hydrogenated halogenated silane comprising a tertiary aliphatic hydrocarbon-substituted amine and a metal chloride or phosphine oxide compound. There is also provided a method for producing monosilane, which comprises a disproportionation reaction of a hydrohalogenated silane in the presence of the liquid catalyst.

Description

  The present invention relates to a catalyst for disproportionation reaction of a hydrogenated halogenated silane compound and a method for producing monosilane using the same.

  In recent years, the demand for monosilane is increasing as a raw material for high purity silicon epitaxy and amorphous silicon for solar cells.

  Various methods for producing monosilane are known, and a method for producing a monohalogenated halogenated silane compound such as trichlorosilane in the presence of a catalyst is well known.

Many compounds are known as catalysts used in the disproportionation reaction of hydrogenated silane halides. For example, a method using a quaternary ammonium salt or a quaternary phosphonium salt as a liquid phase homogeneous catalyst, or an anion exchange resin having a tertiary amine group or a quaternary ammonium group as a solid heterogeneous catalyst. A method is known (Patent Document 1). A method of using a tertiary aliphatic hydrocarbon-substituted amine and its hydrochloride as a liquid phase homogeneous catalyst is also known (Patent Document 2).
Japanese Patent Publication No. 63-16328 Japanese Patent Publication No. 63-33422

  Various catalysts have been known for the disproportionation reaction of hydrohalogenated silanes and production methods of monosilanes using the same, and new catalysts and productions that can further improve the production efficiency of monosilanes. Development of a method was desired.

  For example, the conventional method of supplying a raw material hydrogen halide silane to a fixed bed type reaction tower packed with a general solid heterogeneous catalyst is based on the equilibrium composition of the disproportionation reaction of the hydrogen halide silane. Since the monosilane conversion rate is determined, the conversion rate is not necessarily as high as 10 to 18% conventionally, and a large facility cost is required to obtain a desired production amount. In addition, the anion exchange resin has an improvement in that the maximum use temperature is as low as 100 ° C. and it is difficult to obtain a sufficient reaction rate.

  On the other hand, a conventional method using a quaternary ammonium salt, a quaternary phosphonium salt, a tertiary aliphatic hydrocarbon-substituted amine and its hydrochloride supplies a raw material hydrogenated halosilane to a reaction tower, This is a relatively efficient production method in which a monosilane from the top of the tower and a catalyst containing silicon tetrachloride and a halogenated silane halide are taken out from the bottom of the tower by performing a disproportionation reaction and a distillation operation at once in the tower.

  However, in a catalyst using hydrochloride, a side reaction in which hydrochloric acid is released and hydrogen is generated occurs, and the yield of monosilane is reduced. In addition, when a quaternary ammonium salt or a quaternary phosphonium salt is used, a side reaction in which hydrogen is generated from trichlorosilane as a raw material is generated, so that the yield of monosilane is lowered. Furthermore, since quaternary ammonium salts, quaternary phosphonium salts, tertiary aliphatic hydrocarbon-substituted amines and hydrochlorides thereof are not sufficiently heat resistant, the catalyst is decomposed and deactivated by excessive heating, and smooth. There was also an improvement that continuous operation became difficult.

  The present invention has been made to further increase the production efficiency of monosilane in the production of monosilane by the disproportionation reaction of a hydrogenated halogenated silane. As a result of intensive studies to solve the problem of improving production efficiency in the production of monosilane by disproportionation reaction of hydrogenated silane halides, the present inventors have found that a tertiary aliphatic hydrocarbon-substituted amine, a metal chloride, Alternatively, the inventors have found that the production efficiency of monosilane can be improved by using a liquid catalyst comprising a phosphine oxide compound, and the present invention has been completed.

  That is, according to the present invention, there is provided a liquid catalyst for the disproportionation reaction of a hydrohalogenated silane, comprising a tertiary aliphatic hydrocarbon-substituted amine and a metal chloride or phosphine oxide compound. .

The tertiary aliphatic hydrocarbon-substituted amine is preferably the following formula (1):
Formula (1) R ₁ R ₂ R ₃ N
[In the above formula, R ₁ , R ₂ and R ₃ each represent an aliphatic hydrocarbon group having 2 or more carbon atoms, which may be the same or different.]
It has the structure shown by.

  The metal chloride is preferably at least one selected from copper chloride, zinc chloride and cobalt chloride.

The phosphine oxide compound is preferably the following formula (2):
Formula (2) R ₄ R ₅ R ₆ P═O
[In the above formula, R ₄ , R ₅ and R ₆ each represent a hydrocarbon group having 2 or more carbon atoms which may be the same or different.]
It has the structure shown by.

  Moreover, according to this invention, said liquid catalyst which further contains the solvent which melt | dissolves a metal chloride is provided. More preferably, the liquid catalyst containing a solvent is a liquid phase homogeneous system.

  The liquid catalyst containing the above-mentioned solvent is preferably a metal chloride with respect to a total volume of 100% by volume of the tertiary aliphatic hydrocarbon-substituted amine, the metal chloride, and the raw hydrogen halide silane in the catalyst. 10-60 volume% of the solvent which melt | dissolves a thing is included.

  The solvent for dissolving the metal chloride is preferably composed of at least one selected from ethylene glycol compounds and urea compounds.

  Moreover, according to this invention, the manufacturing method of monosilane including carrying out the disproportionation reaction of hydrohalogenated silane in presence of said liquid catalyst is provided.

It is explanatory drawing which shows an example of the apparatus used for the Example and comparative example of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[Explanation of terms]

  As used herein, “hydrogenated halogenated silane” means a silane compound having at least one hydrogen atom and halogen atom bonded to silicon. Specific examples of the hydrogenated halogenated silane include, but are not limited to, trichlorosilane, dichlorosilane, monochlorosilane, methyldichlorosilane, methylmonochlorosilane, dimethylmonochlorosilane, phenylmonochlorosilane, phenyldichlorosilane, And diphenylmonochlorosilane.

  In the present specification, the “phosphine oxide compound” means a phosphorus-containing compound having an oxygen atom bonded to phosphorus. Specific examples of the phosphine oxide compound include, but are not limited to, tri-n-octylphosphine oxide, tri-n-butylphosphine oxide, triphenylphosphine oxide, butyldiphenylphosphine oxide, and the like.

  In this specification, “disproportionation reaction of hydrogenated halogenated silane” refers to the formation of a compound different from each reactant by exchanging hydrogen and halogen between two molecules of hydrogenated halogenated silane. Reaction.

  In addition, the “liquid” (in the form of a catalyst) in the present specification means a state of a suspension or a solution (liquid phase homogeneous system).

  Further, in the present specification, “including” includes “consisting mainly of”, “consisting essentially of” and “consisting of”, and “consisting mainly of” includes “consisting essentially of” and “Consisting of” is included, and “consisting essentially of” includes “consisting of”.

  In the present specification, “consisting mainly of” is not limited to this, but the target component mentioned is 70% by mass or more, preferably 80% by mass or more, more preferably 90% by mass of the total mass. % Or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, or 99% by mass or more or 100%.

  Each numerical range in the present specification includes an upper limit value and a lower limit value indicated by “to”. For example, the description “A to B” means A or more and B or less.

Embodiment
Hereinafter, although the present invention is explained in detail using the form for carrying out the present invention, the present invention is not limited to this.

<Catalyst>
One aspect of the present invention is a liquid catalyst for the disproportionation reaction of a hydrohalogenated silane comprising a tertiary aliphatic hydrocarbon-substituted amine and a metal chloride or phosphine oxide compound. In the production of monosilane by the disproportionation reaction of a hydrogenated silane halide, the use of this catalyst can increase the production efficiency of monosilane and can produce a continuous monosilane efficiently. In particular, since metal chloride has a high effect of suppressing the amount of hydrogen generated, monosilane can be produced more efficiently, and a catalyst containing a phosphine oxide compound has high heat resistance, so that the reaction can proceed at a high reaction rate at high temperatures. it can. Furthermore, since this catalyst is a liquid, it has the characteristics that reaction rate is high and it is efficient.

  The amount of metal chloride or phosphine oxide compound added when using the liquid catalyst according to the present invention in the production of monosilane is not particularly limited, but is 100 mol% of a tertiary aliphatic hydrocarbon-substituted amine, 5-50 mol% is preferable, 10-40 mol% is more preferable, and 10-30 mol% is still more preferable. When the amount is 5 mol% or more, the catalytic action can be achieved more reliably, and when the amount is 50 mol% or less, generation of hydrogen as a side reaction product can be more effectively suppressed, and the production efficiency of monosilane can be further improved.

  Further, the total addition amount of the tertiary aliphatic hydrocarbon-substituted amine and the metal chloride or phosphine oxide compound when using the liquid catalyst according to the present invention in the production of monosilane is not particularly limited, 5-100 mol% is preferable with respect to 100 mol% of hydrogenated halogenated silanes of a raw material. By mixing in this range, monosilane can be most efficiently produced.

The tertiary aliphatic hydrocarbon-substituted amine used in this embodiment is preferably the following formula (1):
Formula (1) R ₁ R ₂ R ₃ N
[In the above formula, R ₁ , R ₂ and R ₃ each represent an aliphatic hydrocarbon group having 2 or more carbon atoms, which may be the same or different.]
It has the structure shown by. Such a tertiary aliphatic hydrocarbon-substituted amine allows the disproportionation reaction to proceed more smoothly because the tertiary amine functions more reliably as part of the catalyst.

  In the said embodiment, 2 or more are preferable and, as for each carbon number of an aliphatic hydrocarbon group, 6-15 are more preferable. If the aliphatic hydrocarbon group has 2 or more carbon atoms, it is difficult for the catalyst to become a solid when it comes into contact with the hydrohalogenated silane, and smooth continuous operation can be achieved by blocking the reactor column or packing. It can be prevented from disappearing. Further, when the number of carbon atoms is 15 or less, the viscosity of the catalyst becomes low, and a smooth continuous operation can be performed more easily. Specific examples of such an aliphatic hydrocarbon group include, but are not limited to, tri-n-octylamine and tri-n-butylamine.

Further, the metal chloride used in the present embodiment is not particularly limited as long as it is a metal chloride having a catalytic activity mixed with a tertiary aliphatic hydrocarbon-substituted amine. ):
Formula (3) MCl _n
[In the above formula, M represents an alkali metal, alkaline earth metal, transition metal, typical metal, etc., and n represents an integer of 1 or more.]
The thing which has a structure shown by these is mentioned.

  In the above embodiment, examples of the metal M include, but are not limited to, Li, Na, K, Cs and the like (alkali metal), Ca and the like (alkaline earth metal), Cu, Co, Fe, Ni etc. (transition metal), Al, Zn etc. (typical metal) are mentioned.

  Moreover, one embodiment of the present invention is the above liquid catalyst, wherein the metal chloride is at least one selected from copper (II) chloride, zinc (II) chloride and cobalt (II) chloride.

The phosphine oxide compound used in this embodiment is preferably the following formula (2):
Formula (2) R ₄ R ₅ R ₆ P═O
[In the above formula, R ₄ , R ₅ and R ₆ each represent a hydrocarbon group having 2 or more carbon atoms which may be the same or different.]
It has the structure shown by.

  In the above embodiment, the hydrocarbon group may be either an aliphatic hydrocarbon group or an aromatic hydrocarbon group. Moreover, 2 or more are preferable and, as for each carbon number of a hydrocarbon group, 6-15 are more preferable. If the hydrocarbon group has 2 or more carbon atoms, it is difficult for the catalyst to become a solid when it comes into contact with the hydrohalogenated silane, and smooth continuous operation cannot be performed due to blockage of the column or packing of the reaction tower. Can be prevented. Further, if the number of carbon atoms is 15 or less, since the melting point becomes low, it becomes difficult for precipitation to occur in the low temperature part in the reactor, so that it becomes difficult to block the stage and the like, and a smooth continuous operation can be performed more easily. Become. Specific examples of such phosphine oxide compounds include, but are not limited to, tri-n-octylphosphine oxide, tri-n-butylphosphine oxide, triphenylphosphine oxide, butyldiphenylphosphine oxide, and the like. It is done.

  In addition, an embodiment of the present invention is any one of the liquid catalysts described above that further includes a solvent for dissolving the metal chloride and is in the form of a liquid phase homogeneous system. In many cases, a catalyst comprising a tertiary aliphatic hydrocarbon-substituted amine and a metal chloride is in a suspended state. By adding a solvent for dissolving the metal chloride to the suspended catalyst, a catalyst is added. Further, a catalyst having a liquid phase homogeneous system can also be suitably used. By using such a liquid catalyst, monosilane can be produced more efficiently. The solvent for dissolving the metal chloride is not particularly limited as long as it dissolves the metal chloride and does not impair the effects of the present invention, but an ethylene glycol compound or a urea compound is preferable.

The ethylene glycol-based compound is a compound containing a repeating unit of ethylene glycol, and is not limited thereto. For example, the following formula (4):
Equation _{(4) R 7 - (O} -CH 2 CH 2) p -O-R 7
[In the above formula, R ₇ represents an aliphatic hydrocarbon group or hydrogen which may be the same or different, and p represents an integer of 1 or more.]
The compound represented by these is mentioned.

  Here, p is preferably 2 or more, more preferably 2-4. When p is 2 or more, the repeating unit is plural, and it is easy to be compatible with the tertiary aliphatic hydrocarbon amine uniformly. Moreover, if p is 4 or less, the viscosity of a solution will become low and possibility that a smooth continuous operation will become impossible by obstruction | occlusion of the packing in a reactor can be reduced.

R ₇ is preferably an aliphatic hydrocarbon group having 2 or more carbon atoms, more preferably an aliphatic hydrocarbon group having 4 to 6 carbon atoms. When R ₇ is an aliphatic hydrocarbon group having 2 or 4 carbon atoms, it is easy to be compatible with a tertiary aliphatic hydrocarbon amine uniformly. If the number of carbon atoms is 6 or less, the solvent unit price can be reduced. Specific examples of R ₇ include, but are not limited to, an ethyl group and a butyl group.

Examples of urea compounds include, but are not limited to, the following formula (5):
Equation _{(5) (R 8) 2} -N-C (= O) -N- (R 8) 2
[Wherein R ₈ represents an aliphatic hydrocarbon group which may be the same or different from each other]
The compound represented by these is mentioned.

Here, R ₈ is preferably an aliphatic hydrocarbon group having 2 to 4 carbon atoms. If the number of carbon atoms is 4 or less, the solvent unit price can be reduced. Specific examples of R ₈ include, but are not limited to, a methyl group, an ethyl group, a propyl group, and a butyl group.

  The amount of the solvent added when using the liquid catalyst of the above-mentioned form in the production of monosilane is not particularly limited, but the amount of the raw material hydrogenated silane halide added and the catalyst component (tertiary aliphatic hydrocarbon substitution) 10-60 volume% is preferable with respect to a total of 100 volume% with the addition amount of (amine + metal chloride), and 15-50 volume% is more preferable. When the amount of the solvent added is 10% by volume or more, the metal chloride is less likely to precipitate in the reactor. Further, when the amount of the solvent added is 60% by volume or less, the hydrogenated silane halide and the solvent can be more easily separated in the distillation operation, and a stable continuous operation can be performed. Furthermore, by maintaining the concentration of the catalyst in a moderately high state, the conversion rate from the hydrohalogenated silane to the monosilane can be kept good.

<Manufacturing method>
One embodiment of the present invention is a method for producing monosilane, which comprises a disproportionation reaction of a halogenated silane hydride in the presence of any of the liquid catalysts described above.

In the method for producing monosilane, for example, when a catalyst is brought into contact with trichlorosilane, dichlorosilane, or monochlorosilane, dichlorosilane or monochlorosilane is obtained according to the following disproportionation reaction formulas (1), (2), and (3). And monosilane is formed.
2SiHCl ₃ ＳｉSiH ₂ Cl ₂ + SiCl ₄ (1)
2SiH ₂ Cl ₂ Ｓｉ SiH ₃ Cl + SiHCl ₃ (2)
2SiH ₃ Cl Ｓｉ SiH ₄ + SiH ₂ Cl ₂ (3)

  Since the above (1), (2), and (3) are equilibrium reactions, even if the reaction time is increased, the final product, monosilane, does not form 100%, and the product contains monosilane, monochlorosilane. , Dichlorosilane, trichlorosilane and silicon tetrachloride are mixed. Monosilane can be obtained in a higher yield by separating monosilane from the resulting mixture and returning the remainder to the reactor.

The hydrogenated halogenated silane as a raw material in the above-described form is represented by the following formula (6):
Equation _{(6) SiH m X 4-} m
[In the above formula, X represents halogen, and m represents an integer of 1 to 3.]
Indicated by

  Here, the halogen is preferably fluorine, chlorine, bromine or iodine, more preferably chlorine. As the hydrogenated chlorosilane, it is preferable to use one or more selected from trichlorosilane, dichlorosilane, and monochlorosilane, and it is particularly preferable to use trichlorosilane. Trichlorosilane is useful in industrial monosilane production because it is easily commercially available and relatively inexpensive compared to dichlorosilane, monochlorosilane, and the like.

  The disproportionation reaction according to the above embodiment is a suspension heterogeneous reaction or liquid phase homogeneous reaction in which a raw material hydrogen halide silane and a liquid catalyst are mixed, and is either a batch type or a continuous type. May be.

In the production method according to the above aspect, the internal temperature of the reactor when the disproportionation reaction is carried out by using a hydrohalogenated silane as a raw material and contacting the liquid catalyst containing the above metal chloride is 60 to 120 ° C. It is preferable to hold. By keeping the internal temperature at 60 ° C. or higher, it is possible to prevent the catalyst from being deposited. Further, by keeping the internal temperature at 120 ° C. or lower, it is possible to prevent the catalyst from being decomposed and deactivated.
Moreover, although the internal pressure of the reactor at that time depends on the internal temperature of the reactor, it is preferably adjusted to 150 to 260 kPaG within the above temperature range.

In the production method according to the above aspect, the internal temperature of the reactor when the disproportionation reaction is performed by bringing the liquid halogenated silane as a raw material into contact with the liquid catalyst containing the phosphine oxide compound described above is 60 to 200 ° C. It is preferable to hold | maintain, and it is more preferable to hold | maintain at 150-200 degreeC. By keeping the internal temperature at 60 ° C. or higher, it is possible to prevent the catalyst from being deposited. Further, by maintaining the internal temperature at 200 ° C. or lower, it is possible to prevent the catalyst from being decomposed and deactivated. Furthermore, when the internal temperature is maintained at 150 ° C. to 200 ° C., the reaction rate increases and more efficient monosilane production becomes possible.
Moreover, although the internal pressure of the reactor in that case depends on the internal temperature of the reactor, it is preferably adjusted to 150 to 1350 kPaG or 650 to 1350 kPaG within the above temperature range.

The shape of the reactor is not particularly limited as long as the hydrogen halide silane and the catalyst can be mixed, but a distillation column format is preferable in order to produce monosilane efficiently and continuously. .
The distillation column type reaction column is not limited to this, but for example, a packed column packed with packings such as a plate column, Raschig ring or ball ring partitioned by a sieve tray or bubble cap tray column is suitable. Can be used. Since the production of monosilane is a liquid phase reaction through a disproportionation reaction, the reaction tower is preferably a reaction tower having a large liquid hold-up.

  It should be noted that the catalyst and the production method described by the above embodiment are not intended to limit the present invention, but are disclosed for the purpose of illustration. The technical scope of the present invention is defined by the description of the claims, and those skilled in the art can make various design changes within the technical scope of the invention described in the claims.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention should not be construed as being limited thereto.

[Comparative Experiment 1]
Example 1
Experiments were performed using the apparatus having the flow shown in FIG. The reaction tower 1 is a stainless steel distillation tower having a tower diameter of 100 mm, a tower height of 1200 mm, and 10 stages, and a sieve tray was used for each tray. Add 5.0 kg of tri-n-octylamine and 0.48 kg of zinc chloride to the evaporation tank 2 and stir with a stirrer to prepare a suspension catalyst having a zinc chloride amount of 25 mol% with respect to 100 mol% of tri-n-octylamine. The heating medium oil of the jacket was prepared and kept at 100 ° C.

  After the condenser 3 installed at the top of the reaction tower 1 is cooled with ethylene glycol at −30 ° C., the reboiler 4 at the bottom of the reaction tower is heated with an electric heater, and trichlorosilane is added to the third stage from the bottom of the reaction tower 1. It was continuously supplied from the raw material introduction pipe 5 at a flow rate of 0.0 kg / hour. At the same time, the pump 6 for circulating the catalyst was driven to circulate in the 10th stage from the bottom of the reaction tower at a flow rate of 2.28 kg / hour.

The internal pressure of the reaction tower 1 was maintained at 260 kPaG with a gauge pressure while being adjusted by a control valve. Further, the liquid level of the bottom reboiler 4 was adjusted by the control valve 7 so as to keep the liquid level constant, and the reaction liquid containing the catalyst in the bottom reboiler 4 was extracted into the evaporation tank 2. The extracted reaction solution is operated at a temperature higher than the boiling point of tetrachlorosilane generated by the disproportionation reaction and lower than the boiling point of the catalyst or solvent, the hydrohalogenated silane evaporates, and the catalyst or solvent is extracted by the pump 6. Then, it was continuously returned to the 10th place from the bottom of the reaction tower.
When the temperature of the bottom reboiler 4 of the reaction tower was maintained at 110 ° C. and continuous operation was performed for 10 hours, a low boiling point gas was obtained from the top of the tower. When the gas obtained by passing through the condenser 3 was analyzed by gas chromatography, the production amounts of monosilane and hydrogen described in Table 1 were obtained.

Example 2
The metal chloride added to the evaporation tank 2 was changed to 0.46 kg of cobalt chloride to prepare a suspension catalyst having a cobalt chloride content of 25 mol% with respect to 100 mol% of tri-n-octylamine, and a flow rate of 2.45 kg / hour. The conditions were the same as in Example 1 except that the sample was circulated in

Example 3
The tertiary amine added to the evaporation tank 2 is changed to 2.64 kg of tri-n-butylamine and the metal chloride is changed to 0.46 kg of cobalt chloride, and the amount of cobalt chloride with respect to 100 mol% of tri-n-butylamine is 25 mol%. The same conditions as in Example 1 were used except that a suspended catalyst was prepared and circulated at a flow rate of 1.43 kg / hour.

Example 4
6. 15.0 kg of tri-n-octylamine and 0.41 kg of zinc chloride are added to the evaporation tank 2 to prepare a suspension catalyst having a zinc chloride amount of 7 mol% with respect to 100 mol% of tri-n-octylamine. The conditions were the same as in Example 1 except that circulation was performed at a flow rate of 68 kg / hour.

Example 5
To the evaporation tank 2, 5.0 kg of tri-n-octylamine and 0.87 kg of zinc chloride were added to prepare a suspension catalyst having an amount of 45 mol% of zinc chloride with respect to 100 mol% of tri-n-octylamine. The conditions were the same as in Example 1 except that circulation was performed at a flow rate of 31 kg / hour.

Example 6
A suspension catalyst having a zinc chloride amount of 25 mol% with respect to 100 mol% of tri-n-octylamine is prepared in the evaporation tank 2, and 4.63 kg of diethylene glycol dibutyl ether is added as a solvent, and the catalyst solution is stirred with a stirrer. Zinc chloride was completely dissolved. The conditions were the same as in Example 1 except that this liquid phase homogeneous catalyst was circulated at a flow rate of 2.53 kg / hour. In addition, the addition amount of the solvent with respect to 100 volume% of the mixture of the raw material trichlorosilane and the suspension catalyst is 30 volume%.

Example 7
In the evaporation tank 2, a suspension catalyst having a zinc chloride amount of 25 mol% with respect to 100 mol% of tri-n-octylamine is prepared, and 9.40 kg of diethylene glycol dibutyl ether is added as a solvent, and the catalyst solution is stirred with a stirrer. Zinc chloride was completely dissolved. The conditions were the same as in Example 1 except that this liquid-phase homogeneous catalyst was circulated at a flow rate of 5.07 kg / hour. In addition, the addition amount of the solvent with respect to 100 volume% of the mixture of the raw material trichlorosilane and the said suspension catalyst is 50 volume%.

Example 8
In the evaporation tank 2, a suspension catalyst having a zinc chloride amount of 25 mol% with respect to 100 mol% of tri-n-octylamine is prepared. Further, 17.10 kg of diethylene glycol dibutyl ether is added as a solvent, and the catalyst solution is stirred with a stirrer. Zinc chloride was completely dissolved. The conditions were the same as in Example 1, except that this liquid phase homogeneous catalyst was circulated at a flow rate of 8.16 kg / hour. In addition, the addition amount of the solvent with respect to 100 volume% of the mixture of the raw material trichlorosilane and the said suspension catalyst is 65 volume%.

Example 9
A suspension catalyst having a zinc chloride amount of 25 mol% with respect to 100 mol% of tri-n-octylamine is prepared in the evaporation tank 2, and 18.70 kg of tetraethylene glycol is added as a solvent, and the catalyst solution is stirred with a stirrer. Zinc chloride was completely dissolved. The conditions were the same as in Example 1 except that this liquid phase homogeneous catalyst was circulated at a flow rate of 6.40 kg / hour. In addition, the addition amount of the solvent with respect to 100 volume% of the mixture of the raw material trichlorosilane and the said suspension catalyst is 50 volume%.

Example 10
In the evaporation tank 2, a suspension catalyst having a zinc chloride amount of 25 mol% with respect to 100 mol% of tri-n-octylamine is prepared. Further, 4.50 kg of tetraethylurea is added as a solvent, and the catalyst solution is stirred with a stirrer to be chlorinated. The zinc was completely dissolved. The conditions were the same as in Example 1 except that this liquid phase homogeneous catalyst was circulated at a flow rate of 2.94 kg / hour. In addition, the addition amount of the solvent with respect to 100 volume% of the mixture of the raw material trichlorosilane and the suspension catalyst is 30 volume%.

Comparative Example 1
Evaporation tank 2 was charged with 2.5 kg of tri-n-octylamine, and 1.77 mol of hydrogen chloride gas was blown therein to prepare a liquid catalyst containing 25 mol% of tri-n-octylamine hydrochloride. The same conditions as in Example 1 were used except that the catalyst was circulated at a flow rate of 1.28 kg / hour while appropriately supplying hydrogen chloride gas so as to maintain this concentration.

Comparative Example 2
The same conditions as in Example 1 were used except that the catalyst added to the evaporation tank 2 was changed to 2.46 kg of tetra-n-butylammonium chloride and circulated at a flow rate of 1.23 kg / hour.

Comparative Example 3
The same conditions as in Example 1 were used except that the catalyst added to the evaporation tank 2 was only 3.12 kg of tri-n-octylamine and circulated at a flow rate of 1.56 kg / hour.

Comparative Example 4
The conditions were the same as in Example 4 except that only 1.32 kg of diethylene glycol dibutyl ether was added to the evaporation tank 2 and circulated at a flow rate of 0.66 kg / hour. In addition, the addition amount of diethylene glycol dibutyl ether with respect to 100 volume% of trichlorosilane of a raw material is 50 volume%.

In this comparative experiment, the production efficiency of monosilane was examined by adjusting the circulation rate of the catalyst so that the amount of monosilane produced was constant. However, since this reaction is a continuous contact reaction, when the catalyst concentration is low, the contact between the catalyst and trichlorosilane decreases, and finally the target monosilane production amount (about 0.75 kg / hour) May not reach.
When a catalyst that does not contain a tertiary aliphatic hydrocarbon-substituted amine and contains only a metal chloride as a catalyst is used, the reaction apparatus according to this comparative experiment cannot perform solid internal circulation. As a reference, when tested in batch format, the reaction did not proceed and neither monosilane / hydrogen was produced.

In all of the examples using the catalyst of the present invention, the hydrogen / monosilane ratio (ratio of the amount of hydrogen production to the amount of monosilane production) is smaller than that of the comparative example using the conventional catalyst, and monosilane is produced efficiently. I understand that.
For example, although Example 1 produces the same amount of monosilane as Comparative Example 1, the amount of hydrogen produced is reduced by about 50%, and monosilane is produced more efficiently.
Furthermore, in Example 6 in which 30% by volume of the solvent was added to Example 1 and a liquid phase homogeneous catalyst was used, about half the catalyst amount (substantially effective catalyst component was 2.53 kg / hour of circulation flow rate). 1.37 kg / hour), the same amount of monosilane as Example 1 (the circulation flow rate of 2.28 kg / hour is all an effective catalyst component) is produced, and the monosilane is produced more efficiently.

[Comparison Experiment 2]
Example 11
Experiments were performed using the apparatus having the flow shown in FIG. The reaction tower 1 is a stainless steel distillation tower having a tower diameter of 100 mm, a tower height of 1200 mm, and 10 stages, and a sieve tray was used for each tray. Add 2.0 kg of tri-n-octylamine and 0.66 kg of tri-n-octylphosphine oxide to the evaporation tank 2 and stir with a stirrer to tri-n-octylphosphine with respect to 100 mol% of tri-n-octylamine. A catalyst having an oxide ratio of 30 mol% was prepared, and the heat transfer oil in the jacket was heated and kept at 100 ° C.

  After cooling the condenser 3 installed at the top of the reaction tower 1 with -30 ° C ethylene glycol, the bottom reboiler 4 of the reaction tower 1 is heated with an electric heater, and trichlorosilane is placed in the third stage from the bottom of the reaction tower 1. Was continuously supplied from the raw material introduction pipe 5 at a flow rate of 2.0 kg / hour. At the same time, the pump 6 that circulates the catalyst is driven to correspond to 25 mol% as the addition amount of the catalyst (the total of tertiary aliphatic hydrocarbon-substituted amine and phosphine oxide compound, the same applies hereinafter) with respect to 100 mol% of trichlorosilane. It circulated in the 10th stage from the bottom of the reaction tower at a flow rate of 33 kg / hour.

The internal pressure of the reaction tower 1 was maintained at 260 kPaG with a gauge pressure while being adjusted with a control valve. Further, the liquid level of the bottom reboiler 4 was adjusted by a regulating valve 7 so as to keep the liquid level constant, and the reaction liquid containing the catalyst in the bottom reboiler 4 was extracted into the evaporation tank 2. The extracted reaction solution is operated at a temperature higher than the boiling point of tetrachlorosilane generated by the disproportionation reaction and lower than the boiling point of the catalyst or solvent, the hydrohalogenated silane evaporates, and the catalyst or solvent is extracted by the pump 6. Then, it was continuously returned to the 10th place from the bottom of the reaction tower 1.
When the temperature of the bottom reboiler 4 of the reaction tower 1 was kept at 100 ° C. and continuous operation was performed, a low boiling point gas was obtained from the top of the tower. When the gas obtained by passing through the upper condenser 3 was analyzed by gas chromatography every 24 hours up to 240 hours from the start of operation, the amount of monosilane shown in Table 2 was obtained.

Example 12
The conditions were the same as in Example 11, except that the temperature of the bottom reboiler 4 of the reaction tower 1 was maintained at 150 ° C. and the internal pressure of the reaction tower 1 was maintained at 650 kPaG as a gauge pressure.

Example 13
The conditions were the same as in Example 11 except that the temperature of the bottom reboiler 4 of the reaction tower 1 was maintained at 200 ° C. and the internal pressure of the reaction tower 1 was maintained at 1350 kPaG as a gauge pressure.

Example 14
Add 0.37 kg of tri-n-butylphosphine oxide to the evaporation tank 2 and stir with a stirrer to prepare a catalyst having a ratio of tri-n-butylphosphine oxide to 100 mol% of tri-n-butylphosphine oxide of 30 mol%. The conditions were the same as in Example 12 except that the catalyst was added at a flow rate of 1.19 kg / hour, corresponding to 25 mol% as the addition amount of the catalyst with respect to 100 mol% of trichlorosilane.

Example 15
0.48 kg of triphenylphosphine oxide is added to the evaporation tank 2 and stirred with a stirrer to prepare a catalyst having a ratio of triphenylphosphine oxide to 100 mol% of tri-n-octylamine of 30 mol%, to 100 mol% of trichlorosilane. The conditions were the same as in Example 12 except that the catalyst was circulated at a flow rate of 1.24 kg / hr, corresponding to 25 mol%.

Example 16
1.05 kg of tri-n-butylamine was added to the evaporation tank 2 and stirred with a stirrer to prepare a catalyst having a ratio of tri-n-octylphosphine oxide to 30 mol% with respect to 100 mol% of tri-n-butylamine, and trichlorosilane The conditions were the same as in Example 12, except that the catalyst was added at a flow rate of 0.86 kg / hour, corresponding to 25 mol% as the amount of catalyst added to 100 mol%.

Example 17
Add 0.37 kg of tri-n-butylphosphine oxide to the evaporation tank 2 and stir with a stirrer to prepare a catalyst having a ratio of tri-n-butylphosphine oxide to 100 mol% of tri-n-butylphosphine oxide of 30 mol%; The conditions were the same as in Example 16 except that the catalyst was added at a flow rate of 0.71 kg / hour corresponding to 25 mol% as the amount of catalyst added to 100 mol% of trichlorosilane.

Example 18
0.48 kg of triphenylphosphine oxide was added to the evaporation tank 2 and stirred with a stirrer to prepare a catalyst having a ratio of triphenylphosphine oxide to 100 mol% of tri-n-butylamine of 30 mol%. The same conditions as in Example 16 were used, except that the amount of was circulated at a flow rate of 0.77 kg / hour corresponding to 25 mol%.

Example 19
Add 2.0 kg of tri-n-octylamine and 0.17 kg of tri-n-octylphosphine oxide to the evaporation tank 2 and stir with a stirrer to tri-n-octylphosphine with respect to 100 mol% of tri-n-octylamine. A catalyst having an oxide ratio of 7 mol% was prepared, and the same conditions as in Example 12 were used except that the catalyst was circulated at a flow rate of 1.32 kg / hour corresponding to 25 mol% as the amount of catalyst added to 100 mol% of trichlorosilane.

Example 20
Add 2.0 kg of tri-n-octylamine and 1.80 kg of tri-n-octylphosphine oxide to the evaporation tank 2 and stir with a stirrer to tri-n-octylphosphine with respect to 100 mol% of tri-n-octylamine. A catalyst having an oxide ratio of 45 mol% was prepared, and the same conditions as in Example 12 were used except that the catalyst was circulated at a flow rate of 1.36 kg / hr, corresponding to 25 mol% as the amount of catalyst added to 100 mol% of trichlorosilane.

Comparative Example 5
The evaporation tank 2 was filled with 2.56 kg of tri-n-octylamine, and 1.77 mol of hydrogen chloride gas was blown into it to prepare a liquid catalyst containing 25 mol% of tri-n-octylamine hydrochloride. The catalyst was circulated at a flow rate of 1.28 kg / hour while appropriately supplying hydrogen chloride gas so as to maintain this concentration, and the temperature of the bottom reboiler 4 of the reaction tower 1 was maintained at 150 ° C. The conditions were the same as in Example 11 except that continuous operation was performed while maintaining the pressure at 650 kPaG as the gauge pressure.

Comparative Example 6
The conditions were the same as in Comparative Example 5, except that the temperature of the bottom reboiler 4 of the reaction tower 1 was maintained at 200 ° C. and the internal pressure of the reaction tower 1 was maintained at 1350 kPaG as a gauge pressure.

Comparative Example 7
2.86 kg of tri-n-octylphosphine oxide alone was added to the evaporation tank 2 and circulated at a flow rate of 1.43 kg / hour, corresponding to 25 mol% as the amount of tri-n-octylphosphine oxide added to 100 mol% of trichlorosilane. The other conditions were the same as in Example 12.

In this comparative experiment, as shown in Table 2, in the comparative example using the conventional catalyst, when the continuous operation was performed at the tower bottom temperature of 150 ° C., the monosilane production amount was clearly reduced in 120 hours. It is considered that this is because the catalyst was denatured by heating at a high temperature, and the catalyst was deactivated. On the other hand, in the example using the catalyst of the present invention, even if it was continuously operated at 150 ° C. for 240 hours, the production amount of monosilane was not reduced. Further, as seen in Example 13, even if the operation was continued at 200 ° C. for 240 hours, the production amount of monosilane was not decreased, and the temperature was increased from 100 ° C. to 150 ° C., and further to 200 ° C. It can be seen that the amount of monosilane produced increases as the operation continues.
Further, in the comparative example, hydrogen chloride is appropriately replenished so that the concentration of tri-n-octylamine hydrochloride is 25 mol%. Therefore, if hydrogen chloride is not replenished, hydrogen chloride is consumed and the amount of monosilane produced Is reduced. On the other hand, the catalyst of the example had a constant monosilane production amount and could be operated continuously for a long time without supplying components such as hydrogen chloride.

  In the above, this invention was demonstrated based on the Example. It is to be understood by those skilled in the art that this embodiment is merely an example, and that various modifications are possible and that such modifications are within the scope of the present invention.

  By using the liquid catalyst for the disproportionation reaction of the halogenated silane of the present invention, the production efficiency of monosilane can be increased, and the continuous production of monosilane can be performed efficiently.

1. Reaction tower 2. 2. Evaporation tank Condenser 4. 4. Bottom reboiler Raw material introduction pipe 6. Pump 7. Control valve

Claims (9)

  A liquid catalyst for the disproportionation reaction of a hydrogenated halogenated silane, comprising a tertiary aliphatic hydrocarbon-substituted amine and a metal chloride or phosphine oxide compound.   The liquid catalyst according to claim 1, wherein the metal chloride or phosphine oxide compound is 5 to 50 mol% with respect to 100 mol% of the tertiary aliphatic hydrocarbon-substituted amine. A tertiary aliphatic hydrocarbon-substituted amine is represented by the following formula (1):
Formula (1) R ₁ R ₂ R ₃ N
[In the above formula, R ₁ , R ₂ and R ₃ each represent an aliphatic hydrocarbon group having 2 or more carbon atoms, which may be the same or different.]
The liquid catalyst of Claim 1 or 2 shown by these.   The liquid catalyst according to any one of claims 1 to 3, wherein the metal chloride comprises at least one selected from copper chloride, zinc chloride, and cobalt chloride. The phosphine oxide compound is represented by the following formula (2):
Formula (2) R ₄ R ₅ R ₆ P═O
[In the above formula, R ₄ , R ₅ and R ₆ each represent a hydrocarbon group having 2 or more carbon atoms which may be the same or different.]
The liquid catalyst as described in any one of Claims 1-3 shown by these.   The liquid catalyst according to any one of claims 1 to 4, further comprising a solvent that dissolves the metal chloride and having a liquid phase homogeneous system.   Claims containing 10-60% by volume of solvent for dissolving metal chloride with respect to 100% by volume in total of tertiary aliphatic hydrocarbon-substituted amine, metal chloride, and raw material hydrogenated silane halide in the catalyst Item 7. The liquid catalyst according to Item 6.   The liquid catalyst according to claim 6 or 7, wherein the solvent for dissolving the metal chloride is at least one selected from ethylene glycol compounds and urea compounds.   A method for producing monosilane, comprising disproportionating a hydrohalogenated silane in the presence of the liquid catalyst according to any one of claims 1 to 8.

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