JPS61138540A - Disproportionation catalyst of chlorosilane and continuous production of silane compound - Google Patents

Abstract

PURPOSE:To produce efficiently silane in great quantities by using a mixture or a reaction product of both a nitrogen compd. which has an electron donor group other than tertiary amine and hydrogen chloride as a disproportionation catalyst of chlorosilane. CONSTITUTION:A mixture and/or a reaction product of both 98-20mol% nitrogen compd. which has an electron donor group such as oxoamines and nitriles other than tertiary amine and 2-80mol% hydrogen chloride is used as a disproportionation catalyst of chlorosilane. A silane compd. is continuously produced in the quick disproportionation velocity in hard-flocculation by the obtained catalyst.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a chlorosilane disproportionation catalyst and a continuous process for producing a silane compound. Furthermore, [$t, < means tertiary@] A mixture or reactant of a nitrogen compound having an electron-donating group other than an amine and hydrogen chloride is used as a catalyst to carry out a disproportionation reaction of chlorucrane in a reaction column and to separate it by distillation. A method for continuously producing a silane compound, which simultaneously obtains 7-rane compounds such as cyclosilane and monosilane;
It relates to catalysts used in the process.

Demand for dichlorosilane, monosilane, etc. is expected to increase in recent years as raw materials used in semiconductors and Taiyo Zuichi Seiko, and large quantities of these are expected to be produced at 9JJ! There is a demand for good manufacturing.

[Conventional technology]

Silane is converted to KS1HC in the presence of a catalyst according to the equilibrium reaction below.
What is obtained by the unrestricted β-conversion reaction of No. 13 is publicly available.

ftl 28iHCA'3. 281H2CAt2
+ 5iC14f21 2SiH2C12, :'
5IH3C6+ 5iHCA! 3 (31281H3CJ
i' SiH4+ 5iH2CJ2 total 14 481HC/3 4 SiH4+ 3SiC
1!4 As a disproportionation catalyst in this case, Hashira's has been proposed, but it has advantages and disadvantages. For example, in the method using nitriles (U8P 2732282), the reaction temperature is 15
The operation must be performed at 0'O or above, and methods using dimethylformamide or dimethylbutyramide (U8P
3222511) had drawbacks such as the catalyst being susceptible to deterioration.

The purpose is to improve these drawbacks, for example, α-
Oquinoamines include tetramethylurea, N-methylbiaI
Method using J ton etc. (U8P4038371, US
P401B871), tetramethylguanidi”%113
A method using zomethylimida/torizinone, C-caprolactam, trimethylunrylimidazole, etc.
6-1791+3), a method using a higher tertiary amine ('#Gan Sho 58-149996), etc. have been proposed. However, these catalysts have a low disproportionation rate or react with chlorsolane to form a coagulable solid, so stirring is performed in the light to disperse them and cause agglomeration in various parts of the shipboard, causing various operational problems. It had drawbacks such as causing trouble.

[Problem that the invention seeks to solve]

The present inventor has discovered that, as a catalyst effective for disproportionation of chlorosilanes, a 6th class amine or a product prepared by adding hydrogen chloride to a 6th class amine can increase the rate of disproportionation of chlorosilane. Even if it reacts with chlorosilane to form a solid substance, it will be smooth and difficult to aggregate, so it was discovered that the amount of Toradel available for purchase was low, and an application for a patent was filed earlier. As a result of further research, the present inventor found that a nitrogen compound having an electron-donating group exhibits a performance similar to that of a 511-th amine, and came to propose the present invention.

[Means for solving problems]

That is, the first aspect of the present invention is to combine 98 to 20 mol of a nitrogen compound having an electron-donating group excluding a tertiary amine and hydrogen chloride 2.
4? Consisting of a mixture and/or reactant with ~80 molti? It is a disproportionation catalyst for chlorosilane with the characteristic
In the invention, raw material chlorosilane such as trichlorosilane,
A silane compound with more hydrogen atoms than the raw material chlorosilane is obtained from the top of the reaction tower, while a 7-rane compound with more chlorine atoms is obtained from the bottom of the reaction tower. and a catalyst, wherein the disproportionation catalyst is a mixture and/or reactant of 98 to 20 mol of a nitrogen compound having an electron-donating group other than a tertiary amine and 2 to 80 mol of hydrogen chloride. This is a continuous method for producing a silane compound characterized by the following.

Hereinafter, the present invention will be explained in more detail.

Excluding the 6th class amine (nitrogen compounds having an electron-donating group (hereinafter simply referred to as nitrogen compounds having 4 groups) include oxoamines, nitriles, azo compounds, silane compounds, nitro compounds, etc. Oxoamines are preferable, and among them, tetramethylurea, N-methylpyrrolidone, morpholine, C-caprolactam, N-methylpyrrolidone, sarcosine anhyde v5 9, bispentamethyleneurea, 1.3-dimethylthiourea, 1,6-methylimida=f IJ zonone is good, and tetramethylguanisine and trimethylsilylimig-t-ol are also effective.Although these substances show some kind of catalytic action even when used alone, when they coexist with hydrogen chloride, the rate of disproportionation decreases. As it becomes faster, even if one solid substance is formed, it will not aggregate, and will be dispersed well by stirring, so it will not settle in the system.

The ratio of the nitrogen compound that grows the electron donating group and hydrogen chloride is 98 to 20 molar for the former and 2 to 80 molar for the latter. It may be either. If the proportion of hydrogen chloride is less than 2 mol%, the effect of improving the disproportionation reaction rate is small, and if it exceeds 80 mol%, it will mostly exist in the chlorosilane as a catalyst solid,
Liquidity becomes poor. Preferred proportions are 95 to 70 mol of the nitrogen compound having an electron-donating group and 5 to 30 mol of hydrogen chloride.

The catalyst of the present invention has the general formula R,N (where R has 4 carbon atoms
This is preferable because it can improve the 6th class mobility shown by the above alkyl group. The combined amount of tertiary amine is 95 to 5
It is 5 to 95 molti to molti, preferably 50 to 95 molti to 50 to 5 molti. The tertiary amine may be mixed in advance with a nitrogen compound having an electron donating group before adding hydrogen chloride, or hydrogen chloride may be added to a nitrogen compound having an electron donating group and then the tertiary amine may be mixed. Examples of the 31st amine include tri-octylamine, tri-n-butylamine, tri-D-pentylamine, and methyldioctylamine, but tri-octylamine and tri-n-butylamine are most suitable from the viewpoint of availability and effectiveness.

The second aspect of the present invention is to supply the raw material alualane to a reaction tower with a torpedo function in which a disproportionation catalyst is present, and obtain a 7-rane compound having more hydrogen atoms than the raw material chlorosilane from the upper part of the reaction tower, while , a mixed solution consisting of a by-product silane compound containing many chlorine atoms and a catalyst is extracted from the bottom of the reaction tower,
Detailed explanation of the present invention is used as a disproportionation catalyst in a method for continuously producing silane compounds such as monosilane, monochlorosilane, dichlorosilane, etc., in which the silane compound and the catalyst are then separated and the catalyst is transferred to a reaction column. This method uses a catalyst prepared by

This will be explained in more detail below.

In the present invention, chlorosilane is 5iHCl, , 8i
1 or 2 selected from H2CJ2 and 5IH3Cl
Refers to more than a species.

The catalyst sludge relative to the raw material chlorosilane is 2 to 50 mol, preferably 5 to 40 mol. @If the amount of soot exceeds 50 moles, the fluidity of the entire reaction solution will be impaired. Moreover, if it is less than 2 molti, the effect of increasing the rate of unrestricted f is small.

The reaction column used in the present invention is in the form of a distillation column, and is, for example, a plate column partitioned by sheep trays or bubble cap trays, or a packed column optically filled with packing such as Raschig rings or ball rings. Any structure may be used as long as the reaction column has a distillation function, but since the disproportionation reaction of the silane compound according to the present invention is a liquid phase reaction, a reaction column with a large liquid holding capacity is desirable.

The temperature inside the reaction tower is not constant, and a four-way distribution occurs. That is, since separation by distillation is carried out simultaneously with the reaction in the reaction column, the temperature at the top of the column is low and the temperature at the bottom is daylight, but the reaction is usually carried out at a temperature in the range of 10 to 200°C. @
If the temperature is less than 10'C, the reaction rate is so low that the disproportionation reaction will not substantially proceed, and if the temperature exceeds 200C, thermal decomposition of the catalyst tends to occur, which is undesirable. In addition, since the reaction is carried out in a boiling state, the pressure is about 0 to 20 to 9/CM to maintain the reaction degree as described above. The raw material chlorosilane supplied to the reaction tower undergoes reaction and fractionation as described above.
Due to the boiling point difference trap, a immersion degree distribution occurs in the order from the top of the column: 7-tanobran, monochlorosilane, 7-dichloran, 7-trichloran, and silicon tetrachloride.

Next, a description will be given with reference to one drawing. The drawing is an explanatory view of a device using an embodiment button of the present invention. Raw material chlorosilane such as trichlorosilane is supplied to the middle upper stage of the reaction tower 1 through the raw material supply 4f4. The reaction column 1 has a column diameter of 83 sn, a height of 2,
A stainless steel distillation column with 18 plates in order of 000, each tray being a sheep tray with 37 holes in order of pore size of 1.5. The upper part of the reaction tower 1 is a stainless steel condenser 3.
The reaction tower 10 is equipped with a jacket so that it can be cooled by passing methanol dry ice.
A pillar 2 containing a built-in heater with a maximum output of I KW is provided at the bottom.

In the reaction column 1, the disproportionation reaction and the separation by distillation occur simultaneously, and the gas produced by the disproportionation reaction, which is rich in low-boiling components, moves upward and is cooled in the condenser 3, condensing the accompanying high-boiling components. It is condensed in a stainless steel condenser 6 cooled with liquid nitrogen, and collected as a liquid in a collection storage tank 7.

On the other hand, high-boiling components such as trichlorosilane and silicon tetrachloride generated in the disproportionation reaction migrate to the bottom of the column and together with the catalyst,
The liquid is extracted from the +tf errorer 2 into the evaporation tank 9 while its liquid level is adjusted. The evaporator FII 9 consists of a stainless steel container with an internal volume of 3j and equipped with a stirrer, and is provided with a jacket. The evaporator tank 9 is heated at a temperature higher than the boiling point of silicon tetrachloride produced in the disproportionation reaction and lower than the catalyst. Trichlorosilane and silicon tetrachloride extracted from the operated heliboiler 2 are evaporated, collected in a condenser 11 cooled with methanol and ice, and recovered in a storage tank 12.The catalyst remaining in the evaporator tank 9 is transferred to a bonder 10. The hydrogen chloride is extracted from the catalyst and circulated again at the top of the reaction tower 1. In this case, if the hydrogen chloride # in the catalyst does not reach the predetermined level of 111, hydrogen chloride is replenished from the replenishment pipe 13.

〔Example〕

A more detailed explanation will be given below with reference to Examples and Comparative Examples.

Example 1 Contents f500cr-SU8304#auhriL/
- 7 runs of trichloride (with jacket and stirrer)
Using 1 mol of 5iHC7+3), the disproportionation reaction was carried out in a closed state in a, changing the reaction temperature, catalyst type 1, hydrogen chloride addition amount and catalyst addition amount 4: as shown in Table 1, and the disproportionation reaction was carried out in a closed state. The amount of chlorosilane was chromatographed over time.
It was placed in place. Note that the change in the amount of 8iHC#3 in the gas phase corresponds to the @conversion rate, and here Table 1 shows the time until the 5iHCAI3 concentration reaches a constant 1(] and the concentration of 5iH(V3) at that time. In Table 1, the shorter the time, the faster the conversion rate (disproportionality rate), and the lower the a value of 5iHCJ3, the better the conversion rate.Table 1 also shows the equilibrium 5IHC/3a obtained by calculation. Hydrogen chloride was added by pressurizing and sealing a predetermined amount of hydrogen chloride in an autoclave.

Example 2 In Example 1, the raw material 5iHCAi3 was changed to 5ta2c/2
The disproportionation rate was changed to 6 with the 4 juices shown in Table 2, and the time when 4 degrees of ElIH in the phase becomes a constant in chromatography, and the concentration at that time are shown in Table 2. Indicated.

For reference, the equilibrium SiH and gas phase concentrations determined by calculation are shown in Table 2.

Example 6 An experiment was carried out in the same manner as in Example 1, except that a mixture of a tertiary amine and a nitrogen compound serving as a child-donating group to which hydrogen chloride was added was used as a catalyst. The results are shown in Table 3.

Example 4 In Example 3, the raw material was changed to 7 runs of dichloride ((), and the same value as that shown in Example 2 was obtained.

Comparative Example 1 In the same manner as shown in Example 1, an experiment was conducted in which HCI was not added and in which it was added too much. The results are shown in Table 1.

Comparative Example 2 Using the same method as shown in Practical Example 2, experiments were carried out in the case where HC/ was not added and in the case where polyelectrode was added.

Comparative Example 3 As a catalyst, IJ fi octylamine and 7# of tetramethylurea or tetramethylguanidine, metal (
An experiment similar to that in Example 6 was conducted using the same method as in Example 6 (without adding MCI). The results are shown in Table H.3.

The following is Example 5: 21. Fill 1 j of tetramethyl urea, blow in 21 g of hydrogen chloride, adjust the catalyst (69 mol of tetramethyl urea, 23 mol of trioctylamine, 8 mol of HCl), and heat the heat transfer oil in the jacket to 100 g. 'Kept at 0. On the other hand, the upper beam of the reaction tower #! After cooling the I3 with methanol dry ice at 160"C, the lower part of the reaction tower - 2 was heated with an electric heater, and 7 runs of chlorine were added to the reactor at a flow rate of 4.01#/hr. It was continuously supplied from the supply conduit 4. At the same time, the catalyst circulation pump 10 was operated to circulate the catalyst in the evaporator 9 to the reaction tower 1 at a flow rate of 1.07 kg/hrf. Inside the reaction tower 1 Pressure is controlled by control valve 5
The reaction liquid containing the catalyst in the reboiler was extracted to the evaporator 49. The recovered catalyst was continuously circulated to the reaction tower while being supplied with hydrogen chloride gas through the supply pipe 13 at a flow rate of 50/min.

When continuous operation was carried out for 20 hours while maintaining the temperature of siler 2 at the bottom of the reaction column at 85'OK, low boiling point gas was obtained from the top of the column at a rate of 175.9/hr and collected. Storage tank γ
Analysis of the collected liquid by Goschromatography revealed that 80% monosilane, 710.5% monosilane, 710.5% monosilane,
The amount of dichlorosilane was 9.5%.

On the other hand, the chlorouran evaporated in the evaporator 9 was cooled in the condenser 11 and collected at a rate of 3.83 klF/hr. When the composition of the recovered liquid was analyzed by chromatography, it was found that the molar ratio was 48% trichlorosilane and 52% silicon tetrachloride.

Example 6 The evaporation tank 9 was charged with 21 mol of tetramethyl urea, 381 mol of hydrogen chloride was blown in to prepare a catalyst (89 mol of tetramethyl urea, 11 mol of HC), and it was heated at 5709/hr.
The same procedure as in Example 5 was carried out except that the mixture was circulated to the reaction column 1 at a flow rate of . As a result, a low boiling point gas of 164.9/
The moles M of the liquid collected were 79.5% mono7ran, 11.0% monochlorosilane, 8.0% cyclosilane, and 1.5% dichlorosilane. On the other hand, the chlornorane evaporated in evaporation [9] is cooled in condenser 11 to 5.84 k! ; l/hr into storage tank 12. The molar composition of the recovered liquid was 55% trichlorane and 45% silicon tetrachloride.

〔Effect of the invention〕

According to the present invention, the following effects are achieved.

! 11 Compared to conventional catalysts, a conversion rate close to the equilibrium conversion rate can be obtained at a low temperature of 150'O or less.

(Since the time to reach the 21 equilibrium conversion rate is short and the disproportionation rate is high, the equipment can be made smaller.

(3) Since the catalyst does not aggregate, long-term continuous operation is possible.

[Brief explanation of drawings]

The drawing is an explanatory diagram of an apparatus used in an example of the present invention. 1 Reaction tower 2 Refiller 3 Condenser
4 Raw material supply conduit 5 tA control valve
6 Forging machine 7 Collection storage tank 8 Needle pulp tank 9 Evaporator 10 Binde 11 Condenser 12 Storage tank 13 Hydrogen chloride supply pipe

Claims (2)

[Claims] (1) A catalyst for disproportionation of chlorosilane characterized by being composed of a mixture and/or reactant of 98 to 20 mol% of a nitrogen compound having an electron-donating group other than a tertiary amine and 2 to 80 mol% of hydrogen chloride. . (2) Supplying raw material chlorosilane such as trichlorosilane to a reaction column having a distillation function in which a disproportionation catalyst is present,
In a method in which a silane compound having more hydrogen atoms than the raw material chlorosilane is obtained from the upper part of the reaction tower, and a mixed liquid of a silane compound having more chlorine atoms and a catalyst is extracted from the bottom of the reaction tower, the disproportionation catalyst is a third 1. A continuous method for producing a silane compound, which is a mixture and/or reactant of 98 to 20 mol% of a nitrogen compound having an electron-donating group other than a primary amine and 2 to 80 mol% of hydrogen chloride.