JPS60112610A - Preparation of silicon tetrachloride - Google Patents

Abstract

PURPOSE:To retard generation of phosgen and to obtain silicon tetrachloride contg. only small amt. of unreacted chlorine with high rate of reaction by allowing pellets contg. SiO2, C, and SiC in a specified proportion by weight to react with chlorine at high temp. CONSTITUTION:100pts.wt. SiO2, 30-60pts.wt. C, and 1-20pts.wt. SiC were mixed and pelletized with a compression molding machine, a rolling type molding machine, etc. by adding, if necessary, binder (e.g. methyl cellulose). SiCl4, as a target product is obtd. by packing the pellets in a reactor, introducing chlorine into the reactor, and causing reaction at >=1,000 deg.C. By-produced dust discharged in the production of siliceous stone, or aerosil is used for the raw material of SiO2 and coke or carbon black is used as the raw material for carbon. Obtd. SiCl4 is useful as a raw material of silicon for semiconductor.

Description

【発明の詳細な説明】 詳しくは原料として二酸化珪素、炭化＠索及び炭素とを
含有するペレットと塩ｌｇヲ高温下で反応させる四塩化
珪素の製造方法に関するう四塩化珪素（＆α４　）　ｌ
′ｉ、微細シリカ、合成石英、窒化珪素その他種々の有
機珪素化合物の合成原料として有用なものであるだけで
なく、太陽電池用や半導体用のシリコンの原料として重
要なものでろる〜− 従来からＳｔα４の製造方法一種々提案されている。[Detailed Description of the Invention] Specifically, it relates to a method for producing silicon tetrachloride in which pellets containing silicon dioxide, carbide, and carbon as raw materials are reacted with salt at high temperature.
It is not only useful as a raw material for the synthesis of fine silica, synthetic quartz, silicon nitride, and various other organic silicon compounds, but is also important as a raw material for silicon for solar cells and semiconductors. Various methods for producing Stα4 have been proposed.

例えば ｌ）金属珪素又は珪素鉄合金と塩素又は塩化水ｉｔ反応
させる方法。For example, l) A method of reacting metal silicon or silicon-iron alloy with chlorine or chloride water.

２）炭化珪素に塩素を反応させる方法。2) A method of reacting silicon carbide with chlorine.

３）珪石と炭素の混合物に塩素を反応させる方法。3) A method in which a mixture of silica stone and carbon is reacted with chlorine.

などがある。１）及び２）の方法は原料費が高く、その
ためコストが高くなるという欠点がある。又３）の方法
は珪素源として安価な珪石を使用するので、１）及び２
）の方法に比べ原料の点で経済的に有利であるが、その
反応速度が非常に遅くしかも反応温度が高いという欠点
があった。また３）の方法の改良法として、流動厚反応
益に炭素４９〜９８重喰％、二酸化珪素１〜４９重看％
及び炭化珪素０．５〜１０重睦％の割合で存在させ温度
１４５４℃以上にて、塩素と反応させることが提案さｎ
ている。（　ＵＳＰ３１７３７５８　）　Ｌかし、この
方法に２いても反応速ｆ’ｒ上げるために１４５４℃以
上という高温を必要とするという欠点があった。and so on. Methods 1) and 2) have the disadvantage of high raw material costs, resulting in high costs. In addition, method 3) uses inexpensive silica stone as a silicon source, so method 1) and 2
) is economically advantageous in terms of raw materials, but it has the disadvantages that the reaction rate is very slow and the reaction temperature is high. In addition, as an improvement method of method 3), carbon 49 to 98% by weight and silicon dioxide 1 to 49% by weight are added to the flow thickness reaction gain.
It is proposed that silicon carbide be present in a proportion of 0.5 to 10% by weight and reacted with chlorine at a temperature of 1454°C or higher.
ing. (US Pat. No. 3,173,758) However, this method had the drawback of requiring a high temperature of 1454° C. or higher in order to increase the reaction rate f'r.

不発明けこれらの欠点全解決したもので二酸化珪素と炭
水と塩素ケ高温下で反応させ四塩化珪素を製造する方法
に２いて原料として二酸化珪素１００重緻部に対し炭素
及び炭化珪素が、それぞれ３０〜６０重敬部及び１０〜
２０重量部の割合で含有するペレットヲ反応器に充填し
温度１０００℃以上で反応させることを特徴とする四塩
化珪素の製造方法である。The uninvented solution to all of these drawbacks is a method of producing silicon tetrachloride by reacting silicon dioxide, carbon water, and chlorine at high temperatures, and carbon and silicon carbide are used as raw materials for 100 parts of silicon dioxide, respectively. 30~60 important club and 10~
This is a method for producing silicon tetrachloride, characterized in that pellets containing 20 parts by weight are charged into a reactor and reacted at a temperature of 1000° C. or higher.

以下詳しく本発明について説明する。The present invention will be explained in detail below.

二酸化＠素としては、例えば白硅石、鯖波硅石、オノ！
−ル質佳石等の珪石１７エロシリコン等の珪素系合金を
電気炉で製造する際排出される副生ダスト及びアエロジ
ル等が挙げられる。Examples of carbon dioxide include white silica, Sababa silica, and Ono!
- Silica stone such as silica stone 17 Examples include by-product dust and Aerosil, etc., which are discharged when manufacturing silicon-based alloys such as Erosilicon in an electric furnace.

炭素としてはコークス類、無煙炭、木炭、カーボンブラ
ック等が挙げられる。Examples of carbon include coke, anthracite, charcoal, and carbon black.

二酸化珪素、炭素及び炭化珪素を含有するペレットの二
酸化珪素、炭素の構成割合は、二酸化珪素ｉｏｏ重敬部
に対１−１炭素３０〜６０重量部が好ましい。この範囲
外では二酸化珪素と炭素の消費がアンバランスとなり適
当でない。The composition ratio of silicon dioxide and carbon in the pellet containing silicon dioxide, carbon and silicon carbide is preferably 30 to 60 parts by weight of 1-1 carbon to ioo parts of silicon dioxide. Outside this range, the consumption of silicon dioxide and carbon becomes unbalanced and is not appropriate.

また、二酸化珪素と炭化珪素の構成割合は、二酸化珪素
１００重量部に対し炭化珪素１〜２０重゛歇部が好まし
い。こｎより少ないとその作用効果が小さい。また、こ
れより多くしても経済的でなくなる。The composition ratio of silicon dioxide and silicon carbide is preferably 1 to 20 parts by weight of silicon carbide per 100 parts by weight of silicon dioxide. If the amount is less than n, the effect will be small. Moreover, if the number is larger than this, it becomes uneconomical.

二酸化珪素及び炭素は、ロールクラッシャー、ノｆルペ
ライデー、振動ミル、ジェットミル等の粉砕機で微粉化
し各々平均粒径金２００μ以下のものとして使用するこ
とが好ましい。It is preferable that silicon dioxide and carbon be pulverized with a pulverizer such as a roll crusher, a nofleperide, a vibration mill, a jet mill, etc., and used as particles having an average particle size of 200 μm or less.

また、炭化珪素は５００μ以下に粉砕し使用することが
好ましい。Moreover, it is preferable to use silicon carbide after pulverizing it to a size of 500 μm or less.

これら、二喫化＠素、炭素及び炭化珪素の粉を、万能混
合攪拌機、ニーダ−１振動ミル等の混合機で混合する。These powders of carbon dioxide, carbon, and silicon carbide are mixed using a mixer such as a universal mixing stirrer or a kneader-1 vibrating mill.

こｎら原料をペレットとするには結合剤を用いずに、又
は用いてもよいが結合Ｎｉｌ　ｋ用いる場合は結合剤と
して例えば水やポリビニールアルコール、メチルセルロ
ース、カルボキシメチルセルロース糖密等の水溶性結合
剤または、タール、ピッチ等の粘結削金添加（−１こｎ
、’１例えばブリケットマシン、ディスクペレッター等
の圧縮成型機、・母ン型造粒機等の転勤式成形機、更に
押出し成型機等通常の成形方法により成形すればよい。To make these raw materials into pellets, a binder may be used without or with a binder, but if a binder is used, a water-soluble binder such as water, polyvinyl alcohol, methyl cellulose, or carboxymethyl cellulose saccharide may be used as the binder. Addition of agent or caking metal such as tar or pitch (-1
,'1 For example, the molding may be carried out using a compression molding machine such as a briquette machine or a disc pelleter, a transfer molding machine such as a mother-type granulator, or an ordinary molding method such as an extrusion molding machine.

ぺレットの形状はサイコロ状、円柱、球等凹凸の少ない
ものが好ましく、大きさは反応器や供給シュート等・く
レットか通過する部分の最も狭い所のし以下程度の大き
さが適当である。The shape of the pellet is preferably dice-like, cylindrical, spherical, etc. with minimal irregularities, and the appropriate size is about the size of the narrowest part of the reactor, supply chute, etc. where the pellet passes through. .

塩素としては、塩素の他に、ホスダン等の塩素含有ガス
が用いられる。As the chlorine, in addition to chlorine, a chlorine-containing gas such as phosdan is used.

これら反応を行わさせる反応器としては固定床式、流動
床式のものに大別されるが、本発明にひいては固定床式
のものが好ましい。Reactors for carrying out these reactions are broadly classified into fixed bed type and fluidized bed type, but fixed bed type is preferred in the present invention.

なお固定床式の反応器に秒いてもパッチ式及び連続式で
反応させる方法があるが本発明においてはいずれも適用
することができる。There are methods of reacting in a fixed bed reactor, patch method and continuous method, both of which can be applied in the present invention.

パッチ式には反応器にペレツ）を充填したもののみを反
応させる方法とさらに消費された原料に応じて原料を補
給する方法とがあり、連続式には上部からペレットを下
部から塩素含有ガスを連続的に供給し、上部から反応生
成ガスの排出させると共に下部から反応残置を抜き出す
方法等があるが、これらの方法が適用できる装置でるる
ことが必要である。In the patch type, there is a method in which only the reactor is filled with pellets, and there is a method in which the raw material is replenished according to the consumed raw material.In the continuous type, the pellets are fed from the top and chlorine-containing gas is injected from the bottom. There is a method of continuously supplying the reaction product, discharging the reaction product gas from the upper part, and extracting the reaction residue from the lower part, etc., but it is necessary to have an apparatus to which these methods can be applied.

反応器材料としては高温の塩素雰囲気上使用できるもの
であればよいが、具体的には黒鉛などがめげられる。Any reactor material may be used as long as it can be used in a high-temperature chlorine atmosphere, but graphite and the like are specifically recommended.

反応は温度１０００℃以上で行うことができるが好まし
くは１１００〜１４５０℃である。The reaction can be carried out at a temperature of 1000°C or higher, preferably 1100 to 1450°C.

１０００℃未満では反応速度が十分でなく、又１４５０
℃をこえると熱的に不経済となるばかりでなく炉の寿命
が短くなる。If the reaction rate is lower than 1000°C, the reaction rate is not sufficient, and if the temperature is lower than 1450°C,
If the temperature exceeds ℃, it not only becomes thermally uneconomical but also shortens the life of the furnace.

以上説明したように本発明は二酸化珪素、炭素及び炭化
珪素の粉末金ベレントし；こｎを反応器に充填し、高温
下反応させる四塩化珪素の製造方法であって、本発明に
よれば反応速度が向上し未反応塩素の含有毅が少なく、
ホスダンの生成が少ないものが得られるという効果があ
る。As explained above, the present invention is a method for producing silicon tetrachloride, in which powdered gold berent of silicon dioxide, carbon and silicon carbide is charged into a reactor and reacted at high temperature. Speed is improved and less unreacted chlorine is contained.
This has the effect of producing less phosdan.

以下実施例をあげてさらに本発明を具体的に説明する。EXAMPLES The present invention will be explained in more detail below with reference to Examples.

実施例１ 平均粒径３０μの珪石（５ＬＯｔ含有９０％以上）と平
均粒径１６０μのコークスを珪石１００重量部に対しコ
ークス４０重量部となるように混ぜ振動ミルで１時間混
合粉砕して平均粒径５０μとした。Example 1 Silica stone with an average particle size of 30 μm (5LOt content of 90% or more) and coke with an average particle size of 160 μm were mixed so that 40 parts by weight of coke per 100 parts by weight of silica stone were mixed and ground in a vibrating mill for 1 hour to obtain an average particle size. The diameter was 50μ.

その後、この粉砕混合物１００重量部に対して、２２重
量部の水と３５μ以下の炭化珪素３８５重量部を加え、
ニーダ−にて５分間混合した。Then, to 100 parts by weight of this pulverized mixture, 22 parts by weight of water and 385 parts by weight of silicon carbide of 35μ or less were added,
The mixture was mixed in a kneader for 5 minutes.

これをディスクベＶツターテＩ　Ｏ−Ｘ　１０箇のペレ
ットとし、温度１８０℃の乾燥器中で２４時間乾燥した
。乾燥後これを反応容積５ｔの反応器て充填した後、下
部より塩素を毎分２２１供給し、温度１３００℃で反応
させた。This was made into 10 pellets of Discve V Tutate I OX and dried in a dryer at a temperature of 180° C. for 24 hours. After drying, this was filled into a reactor with a reaction volume of 5 tons, and chlorine was supplied from the bottom at a rate of 221 per minute to cause a reaction at a temperature of 1300°C.

反応に伴いペレットが減少するがペレットペルが一定と
なるように反応器上部よりにレットを供給した。The pellets were supplied from the top of the reactor so that the number of pellets decreased as the reaction progressed, but the number of pellets remained constant.

このよってして反応を３日間継続したが、この間生成ガ
ス中の未反応塩素は０．２％以下であり、ホスゲンの生
成は見られなかった。The reaction was thus continued for 3 days, during which time the amount of unreacted chlorine in the produced gas was 0.2% or less, and no phosgene was observed to be produced.

比較例 炭化珪素を添加しなかったことを除き、実施例１と同様
にベレツ）ｋ作った。これを反応容積５ｔの反応器に充
填し、下部より塩素？毎分２２を供給し、温度１３００
℃で反応させたつ 反応に伴いペレットが減少するがペレットレベルが一定
となる↓うに反応器上部よりペレットを供給した。Comparative Example A sample was prepared in the same manner as in Example 1, except that silicon carbide was not added. This was filled into a reactor with a reaction volume of 5 tons, and chlorine was added from the bottom. 22 per minute, temperature 1300
When the reaction was carried out at ℃, the number of pellets decreased as the reaction progressed, but the pellet level remained constant. Pellets were fed from the top of the reactor.

このようにして反応全２４時間継続したが、この間生成
ガス中の未反応塩素は０．２〜５．０％、ホスダンは１
．０２〜１１．５％であった。The reaction continued in this manner for a total of 24 hours, during which time the amount of unreacted chlorine in the generated gas was 0.2 to 5.0%, and the amount of phosdan was 1%.
．． It was 02 to 11.5%.

実施例２ 炭化珪素を６．５電歇部と変えた以外は実施例１と同様
にペレットを作った。これ金反応容４１５　ｔの反応器
に充填し、下部より塩素を毎分３５を供給し、温度１３
００℃で反工６させた。Example 2 Pellets were made in the same manner as in Example 1, except that the silicon carbide was changed to a 6.5-electrode part. This was packed into a reactor with a gold reaction capacity of 415 tons, and chlorine was supplied from the bottom at a rate of 35 tons per minute, at a temperature of 13 tons.
The material was subjected to unwinding at 00°C.

反応に伴いペレットレベルが低下するが、ペレットレベ
ルが一定となるように反応器上部ヨリぺＶット金供給し
た。Although the pellet level decreased with the reaction, gold was supplied to the top of the reactor so that the pellet level remained constant.

このようにして、反応を３日間継続した力よ、この間生
成ガス中の未反応塩素は０．２％以下で、ｆｔ）、ホス
ゲンの生成は見られなかった。In this manner, the reaction was continued for three days, during which time the amount of unreacted chlorine in the produced gas was 0.2% or less (ft), and no phosgene formation was observed.

特許出願人 電気化学工業株式会社patent applicant Denki Kagaku Kogyo Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] 二酸化珪素と炭素と塩素を高温下で反応させ四塩化珪素
を製造する方法に２＾て原料として二酸化珪素１００重
量部に対して炭素及び炭化珪素金それぞれ３０〜６０重
坂部及び１〜２０重量部の割合で含有するペレット金反
応器に充填し温度１０００℃以上で反応させることを特
徴とする四酸化珪素の製造方法。In a method for producing silicon tetrachloride by reacting silicon dioxide, carbon, and chlorine at high temperatures, 2^ carbon and silicon carbide gold are used as raw materials, 30 to 60 parts by weight and 1 to 20 parts by weight, respectively, per 100 parts by weight of silicon dioxide. A method for producing silicon tetroxide, which comprises filling a reactor with pellets containing gold in a proportion of 1,000 to 1,000, and reacting at a temperature of 1000° C. or higher.