JPS61270206A - Production of monosilane - Google Patents

Abstract

PURPOSE:In producing a monosilane by disproportionating an alkoxysilane in the presence of a catalyst, to produce efficiently a monosilane and to make separation of a catalyst from a reaction product easy, by using an anion exchange resin as a catalyst. CONSTITUTION:An alkoxysilane (e.g., trimethoxysilane) shown by the formula (R is 1-6C alkyl; n is 1-3) is disproportionated in the presence of a catalyst consisting of an anion exchange resin, to give the aimed monosilane. A resin obtained by bonding a primary - tertiary amine or quaternary ammonium group as an exchange group to a high polymer base (e.g., styrene/divinylbenzene copolymer) polymerized in a three-dimension is used as the anion exchange resin, and the amount of it used is about 0.1-200wt% based on the raw material alkoxysilane. The prepared monosilane is preferably used as a raw material of high-purity silicon for producing optical fiber, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Sedentary Use] The present invention relates to a method for producing monosilane using an alkoxysilane as a raw material.

[Conventional technology]

Monosilane is used as a raw material for high-purity silicon for semiconductors, as well as for amorphous silicon photoreceptors, solar cells,
It is widely used as a raw material for new ceramic materials.

Many proposals have been made regarding the manufacturability of monosilane. Tokuko Shoj / -20θ daθ, there are seven most effective methods for producing monosilane.
A method for disproportionating triethoxysilane using sodium ethoxide as a catalyst is described.

(ZtO), Sin −-81H, + 781 (OEt
).

[Problem that the invention seeks to solve]

This method also has excellent features such as extremely high catalytic efficiency.
However, since the reaction is carried out in a catalytic liquid phase, the catalyst dissolves in by-products (tetraethoxysilane, etc.), and it is not always easy to separate the catalyst from hookworm substances. There is. As is clear from the above equation, this reaction produces a large amount of by-products, but these by-products are useful as raw materials for silicon compounds, such as high-purity silicon, and the catalyst is removed. It is necessary to.

An object of the present invention is to provide a method for producing monosilane that can efficiently produce monosilane from alkoxysilane as a raw material and easily separate the catalyst from the reaction product.

[Means for solving problems]

In view of the above-mentioned drawbacks, the present inventors have conducted research on catalysts that have high catalytic efficiency and are easy to separate from reaction products, and have found that a certain type of solid catalyst is suitable for this purpose. This discovery led to the present invention.

That is, the present invention disproportionates the alkoxysilane represented by the general formula (I) in the presence of a catalyst υ such as an anion exchange resin to produce R, 81 (OR), n-, ---.・-(I
) (wherein, R is an alkyl group having a carbon number of /~B, and n is /1.
(represents 2 or 3) consists in a method for producing monosilane.

The present invention will be explained in detail below.

The alkoxysilane, which is a raw material used in the present invention, is disclosed in, for example, Japanese Patent Application Publication No. 2003-120003. Kota, Tokukai Akira! It is easily prepared by the method described in j-7≦r.

The disproportionation reaction in the method of the invention is carried out using an anion exchange resin as a catalyst.

The ion exchange resin referred to here is a resin in which a 7-jlj& amine or a double ammonium group is bonded to a three-dimensionally polymerized polymer base as an exchange group, and is a typical example of a polymer base. There are copolymers of mono and styrene, and copolymers of styrene and divinylbenzene.

Ion exchange resins are classified into low crosslinking degree resins with a crosslinking degree of r% or less and high crosslinking degree resins with a higher crosslinking degree depending on the degree of crosslinking of the copolymer, both of which can be used in the present invention. In addition, they are structurally classified into gel-like, porous, and bolus-like shapes depending on their porosity, and any of these shapes can be used in the present invention. Generally available anion exchange resins include chemically stable OJ-salt (R-N・OL).
) form, in normal use using NaOH solution.
Although it is regenerated into the 1i salt (RN, OH) form, in the method of the present invention, either the 02 salt form or the OH salt form can be used.

A specific example of a commercially available anion exchange resin is DiAiON 8A-IOA manufactured and sold by Mitsubishi Chemical Corporation.

HPA-26, FA-30 Otsu, WA-ko θ, WA-jθ
etc. can be mentioned.

The amount of anion exchange resin used as a catalyst can achieve its original purpose with an amount of 0.0/''M or more based on the raw material alkoxysilane, but it is usually in the range of 0.7 to 200% by weight. A concave condition is adopted.

The reaction can be carried out either by a suspension batch type or a fixed bed flow type. In particular, since it can be carried out without any restrictions on the material of the device, it is possible to freely select a suitable reaction type.

Although the reaction can be carried out under normal pressure and temperature, it is possible to sufficiently achieve the purpose; however, it is generally preferable to carry out the reaction under normal pressure and elevated temperature. Although the method according to the invention is not dependent on the temperature, a particularly preferred temperature is 100 to 20°C.

The reaction can be carried out at any pressure from reduced pressure to increased pressure, but normal pressure conditions are superior in operability since the monosilane product ignites instantly when it comes into contact with air.

The raw material alkoxysilane in the present invention may be of a single composition or a mixture.

On the other hand, tetramethoxysilane, which is one of the disproportionation reaction products, and other substances, such as aliphatic saturated hydrocarbons such as hexane and heptane, and alicyclic saturated hydrocarbons such as cyclohexane, may also be used together as a solvent. I can do it.

The reaction is usually carried out in a basin or under an inert gas atmosphere of argon. In particular, the use of nitrogen is suitable for collecting monosilane flocculation.

Next, the method of the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.

〔Example〕

Example: In a pressure-resistant glass autoclave with an internal volume of 100 yd, equipped with a stirring blade, a nitrogen gas inlet pipe, a gas discharge pipe with a cooling pipe, and a liquid charge pipe, a catalyst made by Mitsubishi Kasei, which had been dried under heating with a nitrogen stream, was placed in advance. Anion exchange resins J and j1 of DiA-1ON-WA-30 were charged, and the inside of the autoclave system was sufficiently replaced with nitrogen. After that trimethoxysilane O0,
2m01e was added through the liquid charging tube at room temperature, and stirring was started.

The reaction was carried out at room temperature, and IO monosilane was produced when the catalyst and trimethoxysilane came into contact with each other. Afterwards, the reaction was heated to 2Q"cK and continued for 7 hours until no monosilane was produced. The produced monosilane was analyzed by gas chromatography over time. As a result, the conversion of trimethoxysilane '4971
mo1θchi, monosilane generation 0.04tr7 mole
Met.

After the same reaction, the reaction product was separated and the catalyst was separated. The catalyst is insoluble in the raw materials and reaction products and is easy to separate.

Examples λ to 3 The results obtained by carrying out the method carried out in Example 1 by changing the type of anion exchange resin (all manufactured by Mitsubishi Chemical Corporation), the amount, and the reaction time are shown in Table 1. Each anion exchange resin is soluble in raw materials and reaction products, and the catalyst can be easily separated by introducing the reaction products.

TM811: Trimethoxysilane 131H, Nimonosilane [Efficacy] According to the method of the present invention, monosilane can be easily obtained from flukoxysilane as described above. Moreover, the catalyst used in the present invention is substantially insoluble in the reaction product),
Separation from reaction products is extremely easy. reaction product t
M (rigid material) is useful as a raw material for Ueplant's silicon products, such as high-purity silicon used for applications such as optical fibers, encapsulants, IC devices, and photomasks, and the catalyst can be easily separated. This is of great industrial significance.

Sender: Mitsubishi Chemical Industries, Ltd. Representative Patent Attorney Hase - (7 others)

Claims (1)

[Claims] (1) H_nSi(OR)_4_-_n...(I) (wherein, R is an alkyl group having 1 to 6 carbon atoms, and n is 1 , 2 or 3) A method for producing monosilane by disproportionation, characterized in that an anion exchange resin is used as a catalyst.