JPH053415B2 - - Google Patents
Info
- Publication number
- JPH053415B2 JPH053415B2 JP24796686A JP24796686A JPH053415B2 JP H053415 B2 JPH053415 B2 JP H053415B2 JP 24796686 A JP24796686 A JP 24796686A JP 24796686 A JP24796686 A JP 24796686A JP H053415 B2 JPH053415 B2 JP H053415B2
- Authority
- JP
- Japan
- Prior art keywords
- boric acid
- hearth
- boron oxide
- crucible
- liquid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 claims description 34
- 239000004327 boric acid Substances 0.000 claims description 34
- JKWMSGQKBLHBQQ-UHFFFAOYSA-N diboron trioxide Chemical compound O=BOB=O JKWMSGQKBLHBQQ-UHFFFAOYSA-N 0.000 claims description 34
- 238000010438 heat treatment Methods 0.000 claims description 33
- 229910052810 boron oxide Inorganic materials 0.000 claims description 30
- 239000007788 liquid Substances 0.000 claims description 23
- 238000002844 melting Methods 0.000 claims description 8
- 230000008018 melting Effects 0.000 claims description 8
- 238000000034 method Methods 0.000 claims description 5
- 238000004090 dissolution Methods 0.000 claims 2
- RHBGITBPARBDPH-ZPUQHVIOSA-N (E,E)-piperic acid Chemical compound OC(=O)\C=C\C=C\C1=CC=C2OCOC2=C1 RHBGITBPARBDPH-ZPUQHVIOSA-N 0.000 claims 1
- 238000010924 continuous production Methods 0.000 claims 1
- 229920002472 Starch Polymers 0.000 description 5
- 235000019698 starch Nutrition 0.000 description 5
- 239000008107 starch Substances 0.000 description 5
- 238000004519 manufacturing process Methods 0.000 description 4
- 239000006188 syrup Substances 0.000 description 4
- 235000020357 syrup Nutrition 0.000 description 4
- 239000000919 ceramic Substances 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 229910001220 stainless steel Inorganic materials 0.000 description 3
- 239000010935 stainless steel Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 239000002253 acid Substances 0.000 description 2
- 230000018044 dehydration Effects 0.000 description 2
- 238000006297 dehydration reaction Methods 0.000 description 2
- 239000006260 foam Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001131 transforming effect Effects 0.000 description 1
Landscapes
- Crucibles And Fluidized-Bed Furnaces (AREA)
- Saccharide Compounds (AREA)
Description
【発明の詳細な説明】
本発明は、含量が98％以上の高純度酸化ホウ素
の連続製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously producing high purity boron oxide with a content of 98% or more.
ホウ酸酸化物には各種の酸化物があるが、本発
明は一般に三酸化二ホウ素（B2O3）を指すもの
で、通常酸化ホウ素はホウ酸を加熱脱水してつく
られるもので無水ホウ酸とを称されている。ホウ
酸を加熱脱水して酸化ホウ素を製造する場合にお
いて、含量85％程度の酸化ホウ素を得る場合は、
ホウ酸を比較的低い温度、即ち230℃前後の温度
で所要時間加熱すれば得られるが、本発明の意図
する含量98％以上の高純度の酸化ホウ素を得る場
合にはきわめて高温で加熱するため装置的に種々
の問題が生じる。 There are various types of boric acid oxides, but the present invention generally refers to diboron trioxide (B 2 O 3 ), and boron oxide is usually made by heating and dehydrating boric acid. It is called an acid. When producing boron oxide by heating and dehydrating boric acid, to obtain boron oxide with a content of about 85%,
Boric acid can be obtained by heating boric acid at a relatively low temperature, that is, around 230°C, for the required time, but in order to obtain high purity boron oxide with a content of 98% or more as intended by the present invention, it must be heated at an extremely high temperature. Various problems arise with the equipment.
ホウ酸は加熱脱水により酸化ホウ素に変化する
過程において、まず150〜200℃で溶液状となり、
その後加熱脱水がすすむにしたがつて次第に粘度
を増し、温度が250〜450℃、含量で90〜98％位に
なると粘着性の強い泡状となり、その後酸化ホウ
素の融点に近ずくにつれて再び溶融状態となつて
融点（577℃）を越えると水飴状の粘度の高い液
状に溶融して含量98％以上の高純度の酸化ホウ素
（無水ホウ酸）となる性質を有している。したが
つて、このような含量98％以上の高純度の酸化ホ
ウ素を得る場合には高温であるため容器（ルツ
ボ）の材質を選定する必要があり、従来一般には
白金ルツボが用いられているが、高価なために大
型のルツボを使用することができずに小型のルツ
ボを使用するため生産性が少く、しかも前述の如
く水飴状の高粘度のため取出しが困難であつた。 In the process of converting boric acid into boron oxide by heating and dehydration, it first becomes a solution at 150 to 200℃,
After that, the viscosity gradually increases as the heating dehydration progresses, and when the temperature reaches 250-450℃ and the content reaches about 90-98%, it becomes a sticky foam, and then it becomes molten again as it approaches the melting point of boron oxide. When the melting point (577°C) is exceeded, it melts into a highly viscous liquid similar to starch syrup and becomes highly pure boron oxide (boric anhydride) with a content of 98% or more. Therefore, in order to obtain such high purity boron oxide with a content of 98% or more, it is necessary to select the material of the container (crucible) due to the high temperature, and conventionally platinum crucibles have been generally used. However, because it is expensive, it is not possible to use a large crucible, and instead a small crucible is used, resulting in low productivity.Moreover, as mentioned above, it is difficult to take out the product because of its high viscosity like starch syrup.
本発明は、低温加熱容器と高温の加熱炉を別個
に設け、低温加熱容器でホウ酸（粉末）を150〜
200℃程度に加熱して液状体とし、この液状ホウ
酸を加熱炉内のルツボに送液管を介して連続的に
供給するもので、加熱炉は炉材をステンレスかセ
ラミツクとし、炉床を傾斜して形成し、炉床の傾
斜の高い部位に液状のホウ酸受け容器を配し、こ
の容器内に連続的に液状ホウ酸を供給して加熱濃
縮させ、容器から溢出した濃縮液状のホウ酸を傾
斜した炉床に流し、炉内の温度を順次高温にし、
最終的には酸化ホウ素の融点以上の700℃程度に
することによつて連続的に高純度の酸化ホウ素を
得るものであり、炉床を流下させることによつて
熱効率がきわめて良く短時間の間に酸化ホウ素を
高温に導くことのできる高純度の酸化ホウ素の製
造方法を提供するものである。 In the present invention, a low-temperature heating container and a high-temperature heating furnace are provided separately, and boric acid (powder) is heated to
The liquid boric acid is heated to about 200℃ to form a liquid, and this liquid boric acid is continuously supplied to the crucible in the heating furnace via a liquid pipe.The heating furnace is made of stainless steel or ceramic, and the hearth is made of stainless steel or ceramic. A liquid boric acid receiving container is arranged at the high slope part of the hearth, and liquid boric acid is continuously supplied into this container and concentrated by heating, and the concentrated liquid boric acid overflowing from the container is collected. Acid is poured into a sloping hearth, and the temperature inside the furnace is gradually raised to high temperatures.
Ultimately, high-purity boron oxide is obtained continuously by heating the temperature to about 700℃, which is above the melting point of boron oxide, and by flowing down the hearth, it is extremely efficient and can be produced for a short period of time. The present invention provides a method for producing high-purity boron oxide, which can bring boron oxide to a high temperature.
添付図面により本発明の実施例を説明すると第
１図は本発明の一実施例を示し、第２図は別の実
施例を示すものである。 Embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 shows one embodiment of the invention, and FIG. 2 shows another embodiment.
第１図においてA′は低温加熱容器であり、１
０は容器でありこの形状および大きさは任意であ
る。１１は原料投入口であつて１２は水蒸気の排
気口を示す。１３はモーター１４によつて回転す
る撹拌器であり、１５は送液管であつて、この管
路の途中に送液開閉用のバルブ１６を配してい
る。そして本発明にあつては、この低温加熱容器
A′とは別個に高温の加熱炉を設けるものである。
またＢはバーナーやヒーター等の加熱器である。
そして、モーター１４により回転する撹拌器１３
は容器１０内の中心部に位置しており所望に応じ
て設けるものである。この低温加熱容器A′は原
料投入口１１から粉末状のホウ酸が投入され、加
熱器Ｂによつて150〜200℃に加熱されて液状化さ
れる。そしてこの液状化されたホウ酸は送液管１
５を経て加熱炉Ａのルツボ２内に導入される。Ａ
は加熱炉であり、天井部材１と炉床１′とよりな
り炉材としてはステンレスあるいはセラミツクが
使用される。炉床１′は適度に傾斜させて構成し
てあり、加熱炉Ａは炉床の傾斜の高い部位に上面
開放型のルツボ２を配し、炉のルツボ側の天井１
に空気抜き孔７を設けると共に炉床傾斜の最低部
に酸化ホウ素流下取出口６を設け、炉の天井１内
面にはヒーター８を配してある。このヒーター８
の配置は好ましくは炉床の傾斜に従つて高い方向
から低い方向にかけて順次炉内が高温になる如く
配置するものとする。したがつて炉Ａ内の温度は
ルツボ２附近の(イ)の位置においては一番低く150
〜200℃程度とし、ルツボ２の隣接する附近の(ロ)
の位置では250〜450℃程度とし、炉床の傾斜の一
番低い部分では酸化ホウ素の融点577℃よりも高
い700℃前後となるようにヒーター８を配置する。
図中の符号３はルツボ２に連続供給されるホウ酸
が加熱されて濃縮溶液状となつている状態を示
し、４はルツボ２から溢出して炉床でさらに加熱
されて泡状に変形している酸化ホウ素の状態を示
し、５は炉床をさらに流下して加熱されて水飴状
に溶融している酸化ホウ素の状態を示している。 In Figure 1, A' is a low temperature heating container, and 1
0 is a container whose shape and size are arbitrary. 11 is a raw material input port, and 12 is a steam exhaust port. 13 is an agitator rotated by a motor 14, and 15 is a liquid feeding pipe, and a valve 16 for opening and closing liquid feeding is disposed in the middle of this pipe. In the present invention, this low temperature heating container
A high-temperature heating furnace is provided separately from A'.
Further, B is a heater such as a burner or a heater.
A stirrer 13 rotated by a motor 14
is located at the center of the container 10 and may be provided as desired. Powdered boric acid is charged into this low-temperature heating container A' through a raw material input port 11, and is heated to 150 to 200°C by a heater B to be liquefied. Then, this liquefied boric acid is transferred to the liquid sending pipe 1.
5 and is introduced into the crucible 2 of the heating furnace A. A
The heating furnace is composed of a ceiling member 1 and a hearth 1', and stainless steel or ceramic is used as the furnace material. The hearth 1' is constructed with a moderate inclination, and the heating furnace A has an open-top crucible 2 on the high slope of the hearth, and the ceiling 1 on the crucible side of the furnace.
An air vent hole 7 is provided in the furnace, and a boron oxide flow outlet 6 is provided at the lowest part of the slope of the hearth, and a heater 8 is provided on the inner surface of the ceiling 1 of the furnace. This heater 8
The arrangement is preferably such that the temperature inside the furnace increases sequentially from the higher direction to the lower direction according to the inclination of the hearth. Therefore, the temperature inside furnace A is the lowest at position (a) near crucible 2, which is 150°C.
~200℃, and (b) in the vicinity of crucible 2.
The heater 8 is arranged so that the temperature is about 250 to 450°C at the position and the temperature at the lowest slope of the hearth is about 700°C, which is higher than the melting point of boron oxide, 577°C.
In the figure, numeral 3 indicates that the boric acid that is continuously supplied to the crucible 2 is heated and becomes a concentrated solution, and numeral 4 indicates that the boric acid that is continuously supplied to the crucible 2 is heated and becomes a concentrated solution. 5 shows the state of boron oxide flowing down the hearth and being heated and melted into a starch syrup-like state.
第２図は別の実施例を示すものであつて、第１
図の実施例と比較して、ルツボ２に代えて炉床
１′の傾斜面の最上部位置に凹部２′を形成し、こ
の凹部２′を溶液状のホウ酸３の溜容器とするも
のである。そしてこの他の部分は第１図の炉Ａと
同一の構成であるから同一符号を付してある。 FIG. 2 shows another embodiment, in which the first
Compared to the embodiment shown in the figure, a recess 2' is formed at the top of the inclined surface of the hearth 1' instead of the crucible 2, and this recess 2' is used as a reservoir for the boric acid 3 in solution form. It is. Since the other parts have the same structure as the furnace A in FIG. 1, they are designated by the same reference numerals.
次に本発明の製造方法を詳記すると、低温加熱
容器A′に粉末のホウ酸（含水量約44％）が投入
され、この容器A′内は加熱器Ｂによつて150〜
200℃に加熱され、粉末のホウ酸は液状化する。
この液状化したホウ酸は送液管を通してバルブに
よつて流量を調整したホウ酸は常にルツボ２に導
入される。加熱炉Ａの炉内の温度はルツボ２のあ
る(イ)の位置では150〜200℃、ルツボ２から炉Ａ中
央にかけての(ロ)の位置では250〜450℃とし、炉床
の終端附近では600〜700℃となる如くヒーター８
を位置しておく。前述のルツボ２内のホウ酸は加
熱されて濃縮する。この際連続的にホウ酸を供給
すると濃縮された液状ホウ酸３は図中矢印のよう
にルツボ２から溢出して炉床１′上に流下し、炉
内(ロ)の位置においてさらに加熱されて泡状の酸化
ホウ素に変形しながら傾斜している炉床１′上を
徐々に流下して(ハ)の位置の達する。この(ハ)の位置
において酸化ホウ素はさらに融点（577℃）以上
に加熱されるため泡状から水飴状に変形して取出
口６から流下して回収される。 Next, the manufacturing method of the present invention will be described in detail. Powdered boric acid (water content: about 44%) is put into a low-temperature heating container A', and the temperature inside this container A' is
When heated to 200°C, the powdered boric acid liquefies.
This liquefied boric acid is constantly introduced into the crucible 2 through a liquid feeding pipe, the flow rate of which is adjusted by a valve. The temperature inside the heating furnace A is 150 to 200°C at the position (a) where the crucible 2 is located, 250 to 450°C at the position (b) from the crucible 2 to the center of the furnace A, and the temperature is 250 to 450°C near the end of the hearth. Heater 8 so that the temperature is 600-700℃
position. The boric acid in the crucible 2 described above is heated and concentrated. At this time, when boric acid is continuously supplied, the concentrated liquid boric acid 3 overflows from the crucible 2 as shown by the arrow in the figure and flows down onto the hearth 1', where it is further heated at the position inside the furnace (b). The boron oxide gradually flows down on the sloping hearth 1' while transforming into a foamy boron oxide, reaching the position (c). At this position (c), the boron oxide is further heated above its melting point (577° C.), so that it changes from a foam shape to a starch syrup shape, flows down from the outlet 6, and is recovered.
この工程中脱水された水蒸気は空気抜き孔７か
ら炉Ａ外に放出される。また取出口６から回収さ
れた酸化ホウ素は含量98％以上、即ち含水量２％
以下で完全な無水ホウ酸に近く、高温で取出され
た酸化ホウ素は直ちに冷されて固化するから適当
に粉砕して所要のメツシユに調整される。 The water vapor dehydrated during this process is released to the outside of the furnace A through the air vent hole 7. In addition, the boron oxide recovered from the outlet 6 has a content of 98% or more, that is, a water content of 2%.
Below, boron oxide, which is close to complete boric anhydride and taken out at high temperature, is immediately cooled and solidified, and is then appropriately ground to form the required mesh.
また第２図の実施例にあつてもその製造方法は
全く同じであつて、炉床１′の凹部２′に液状ホウ
酸を連続的に供給して加熱すると濃縮した液状ホ
ウ酸３は凹部２′の溶解溜から溢出して炉床上を
流下して加熱されることにより泡状から水飴状に
脱水されながら変形して含量98％以上の高純度の
酸化ホウ素を得ることができる。 The manufacturing method of the embodiment shown in FIG. 2 is exactly the same, and when liquid boric acid is continuously supplied to the recess 2' of the hearth 1' and heated, the concentrated liquid boric acid 3 is transferred to the recess 2'. It overflows from the melting tank 2', flows down on the hearth, and is heated, dehydrated and deformed from a foamy shape to a starch syrup shape, making it possible to obtain highly pure boron oxide with a content of 98% or more.
以上本発明の製造方法を説明したが、本発明に
よるときは、酸化ホウ素が傾斜している炉床を
徐々に流下するためヒーターの加熱による熱効率
がきわめてよく、極く短時間で所望の温度に加熱
されるものであるからホウ酸の融点以上700℃程
度までも容易であり、しかも連続的に高純度の酸
化ホウ素を製造しうるという従来法にはみられな
い画期的効果を奏する。 The manufacturing method of the present invention has been described above, and in accordance with the present invention, the boron oxide gradually flows down the inclined hearth, so the thermal efficiency of heating by the heater is extremely high, and the desired temperature can be reached in an extremely short time. Since it is heated, it is easy to reach temperatures above the melting point of boric acid, about 700°C, and it has the revolutionary effect of being able to continuously produce high-purity boron oxide, which is not seen in conventional methods.
第１図は本発明の実施例を示す断面図であり、
第２図は別の実施例を示す断面図である。
１……炉の天井部、１′……炉床、２……ルツ
ボ、２′……溶液溜、３……液状ホウ酸、６……
取出口、７……空気抜き孔、８……ヒーター、１
０……低温加熱容器、１１……原料入口、１３…
…撹拌器。
FIG. 1 is a sectional view showing an embodiment of the present invention,
FIG. 2 is a sectional view showing another embodiment. 1... Furnace ceiling, 1'... Hearth, 2... Crucible, 2'... Solution reservoir, 3... Liquid boric acid, 6...
Outlet, 7... Air vent hole, 8... Heater, 1
0... Low temperature heating container, 11... Raw material inlet, 13...
...Agitator.
Claims (1)
該低温加熱容器と加熱炉内のルツボを送液管で結
び、該低温加熱容器A′でホウ酸を液状に加熱し、
該液状ホウ酸を送液管を通して加熱炉内のルツボ
に導入し、一方加熱炉Ａの炉床を適度に傾斜さ
せ、該傾斜炉床の高い部位に上面開放状のルツボ
を配置し、炉上面に加熱用のヒーターを配し、傾
斜炉床の最低部に酸化ホウ素流下取出口を設け、
ルツボ内に低温加熱容器A′より液状ホウ酸を連
続的に供給して充満させながらヒーターにより加
熱して濃縮化してルツボの傾斜側より溢流した濃
縮液状ホウ酸を炉床面に自然流下させて順次ヒー
ターにより高温に加熱し、炉床最終端附近で酸化
ホウ素の融点以上に加熱することによつて高純度
の酸化ホウ素を取出口から得ることを特徴とした
酸化ホウ素の連続製造方法。 ２ 傾斜させた炉床の上部位置に凹部を形成し、
該凹部をホウ酸溶解溜とし、該ホウ酸溶解溜に低
温加熱容器から連続的に液状ホウ酸を供給する特
許請求の範囲１に記載の高純度酸化ホウ素の連続
製造方法。[Claims] 1. A low-temperature heating container A' and a heating furnace A are provided separately,
The low-temperature heating container and the crucible in the heating furnace are connected with a liquid pipe, and boric acid is heated to a liquid state in the low-temperature heating container A′,
The liquid boric acid is introduced into a crucible in a heating furnace through a liquid pipe, and the hearth of heating furnace A is appropriately inclined, and a crucible with an open top is placed in a high part of the inclined hearth. A heater is installed in the slanted hearth, and a boron oxide flow outlet is installed at the lowest part of the slanted hearth.
Liquid boric acid is continuously supplied from the low-temperature heating container A' into the crucible, and while the crucible is filled, it is heated by a heater and concentrated, and the concentrated liquid boric acid that overflows from the inclined side of the crucible is allowed to naturally flow down to the hearth surface. A method for continuous production of boron oxide, characterized in that high-purity boron oxide is obtained from an outlet by successively heating the boron oxide to a high temperature with a heater and heating it to a temperature higher than the melting point of boron oxide near the final end of the hearth. 2. Forming a recess in the upper part of the inclined hearth,
The method for continuously producing high-purity boron oxide according to claim 1, wherein the recess is used as a boric acid dissolution reservoir, and liquid boric acid is continuously supplied to the boric acid dissolution reservoir from a low-temperature heating container.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24796686A JPS63103819A (en) | 1986-10-17 | 1986-10-17 | Continuous production of high-purity boron oxide |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24796686A JPS63103819A (en) | 1986-10-17 | 1986-10-17 | Continuous production of high-purity boron oxide |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63103819A JPS63103819A (en) | 1988-05-09 |
| JPH053415B2 true JPH053415B2 (en) | 1993-01-14 |
Family
ID=17171203
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24796686A Granted JPS63103819A (en) | 1986-10-17 | 1986-10-17 | Continuous production of high-purity boron oxide |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63103819A (en) |
-
1986
- 1986-10-17 JP JP24796686A patent/JPS63103819A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63103819A (en) | 1988-05-09 |
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