JPS62182112A - Production of boron oxide - Google Patents

Abstract

PURPOSE:To enable economical and continuous production of boron oxide at a reduced cost, by heating liquid boric acid at a temperature to cause swelling of the liquid in the form of bubbles and collecting the bubbles discharged out of the heating vessel. CONSTITUTION:A low-temperature heating vessel 1 and a high-temperature heating vessel 8 are heated by respective heaters 7, 12 and a proper amount of boric acid used as a raw material is put into the vessel 1. When the boric acid is heated to about 150 deg.C, it is introduced into the vessel 8 via a liquid channel 9. The introduction of the liquid boric acid is temporarily stopped when the level of the liquid in the vessel 8 reaches equal height to that of the liquid in the vessel 1. When the liquid temperature is raised to about >=240 deg.C, the liquid boric acid is gradually swollen in the form of bubbles having strong stickiness. The bubbles are overflowed from a delivery port 10, spontaneously and continuously discharged out of the vessel in dangled state and collected in a receiving vessel 11 to obtain boron oxide bubbles. Since the collected bubbles are instantly cooled and solidified, a powdery boron oxide powder having desired particle size can be produced by crushing the solidified bubbles.

Description

[Detailed Description of the Invention] (Field of use in medicine) The invention relates to a method for producing boron oxide from boric acid, more specifically, boric acid is is 909 to 98% (water-containing lid 10X to 2%)
This invention relates to a method for producing boron oxide that takes advantage of its property of changing to a bubbling state between two positions.

(Prior Art) Boron oxide is usually produced by heating and dehydrating boric acid, and is also called boric anhydride.

How w1. When producing boron oxide based on tt heating and dehydration, as specified in JI 8-8431-61, boron oxide with a ff content of about 185 It is only necessary to heat the acid to a temperature of around 230℃ for a predetermined period of time, and since the state of boric acid at this time is a slightly viscous liquid, its production is easy. It can be manufactured at temperatures as low as about 200°C.

However, when attempting to obtain boron oxide with a content of 90X or more, and therefore a water content of 109X or less.

face various problems.

That is, as shown in Figures 3 (a) to (e), in the process of converting boric acid (powder) into boron oxide through heating and dehydration, it is first bath-dissolved at 150°C to 200°C, and then... 3
As shown in Figure (b), this boric acid liquid B becomes viscous as it is heated and dehydrated.
As shown in Figure 73, it becomes a rather viscous liquid C. And, dehydration of this rather sticky liquid C is further progressing, and f:ilt is about 909 to 98% (water content t 10
X to 29th place), temperature between 240℃ and 500℃ (there is some variation depending on the heating rate)? As shown in Fig. 3 and 4, it becomes a state in which a highly viscous foam is blown (a state in which the foam is carved into bubbles). After that, the melting point (5
As the temperature approaches 77°C, the foamy appearance disappears.
When the melting point is exceeded, it becomes a viscous molten material E, similar to starch syrup or molten glass, as shown in Figure 3 (E).

Boric acid has the above-mentioned properties, and when producing boron oxide with a content of 90X or more (water content of 10% or less), conventionally a crucible is used, and the axils of boric acid are placed inside the crucible, and the melting point (
Boric acid is heated for a long time at a temperature of 577℃ or higher to melt it into a viscous molten substance such as starch syrup, which is then poured out of the crucible into another container and cooled, or placed in the crucible. A manufacturing method in which cooling is occasionally performed from the outside is generally employed.

(Problems to be Solved by the Invention) With the above-mentioned conventional technology, it is possible to obtain commercially available boron with extremely high exfoliation (content of 98 circles or more), but this production method has the following problems. I'm doing it.

(In the conventional method, boric acid is melted until it becomes a viscous melt like an aqueous layer.) Therefore, it takes a long time to manufacture and increases fuel costs.

(ROlA/Removal of the product melted in the pot is complicated.

(c) It is a well-known fact that boric acid and borates dissolve metal oxides at high temperatures. Therefore, according to the conventional method, if the material of the crucible is not carefully selected, the melting of the crucible may occur. C products may be contaminated with impurities and problems may arise with respect to the durability of the crucible.Therefore, conventionally, platinum crucibles have been used, which has the problem of being expensive.

Depending on the application, 4F4 oxide hook rope can be used with a violet content of about 90% to 98% (water content LUX - about 5%); If the mold is heated to the point where it becomes solid, the temperature of the mold becomes 98X or higher, which may result in unnecessary labor costs.

It is an object of the present invention to solve the above-mentioned problems (2) and, in addition, to provide a method for producing boron oxide, which can continuously produce boron oxide.

(How to solve the problem lol!) As a means to solve the above problem, the first feature of the present invention is that when boric acid is placed in a container and heated and dehydrated, the boric acid is removed from the rut stage. When the melting point is exceeded, during the process of changing to a viscous molten substance like starch syrup, if the content is between about 909 to 98X (water content about 10% to 2X), it will swell into bubbles. Focusing on the fact that the foam has sexual activity, we collect it at this stage by sequentially discharging the foam from the top of the container to the outside of the container.

In addition, the second feature of the present invention is that, when boric acid is placed in a container and dehydrated by heating, boric acid has the property of becoming liquid at 150°C to 200°C. First, boric acid (powder) is heated in a container separate from the #Kiyaki to make it into a liquid, and this boric acid liquid is automatically supplied into the container.

That is, the present invention comprises a low-temperature heating container, and a high-temperature heating container connected to the heating container through an infusion channel and arranged so that the low-temperature heating container and the liquid flow through each other due to a difference in liquid level. is heated in a low-temperature heating container while maintaining the temperature at which the boric acid becomes liquid, and the boric acid liquid that changes to a liquid state by the heating and is introduced into the high-temperature heating container is heated in a high-temperature heating container,
The temperature at which the boric acid liquid swells into a foam is heated while being maintained, and the boric acid foam, which changes into a foam and becomes colored due to the heating, is sequentially transferred from the upper side of the high-temperature heating container to the outside of the container. It is characterized by being discharged and collected.

(Function) Boric acid is placed in a low-temperature heating container, and heated with a burner from outside the container.
When heated with a heat source such as an electric heater, the boric acid in the container dehydrates and becomes a liquid at a temperature of 150 to 200"C, and this liquid boric acid is introduced into the high-temperature heating container through the liquid path. When the liquid levels of the liquid in the high-temperature heating container and the liquid in the low-temperature heating container match, the introduction of the liquid is temporarily stopped.

Then, the boro [fi]-like body in the high-temperature heating container is further heated at a high temperature in the container, and as dehydration progresses, it becomes viscous until the water content is below IOX (10% to 2X).
If the temperature of the liquid differs from about 240° C. or higher (in the range of about 240° C. to 500° C.) (however, there is a slight difference depending on the heating rate), the liquid material will become foamy and swell.

By keeping the temperature of the liquid at the above temperature and continuing heating, the foam rises above the height of the container, so acid leaks from the top of the container and flows out of the container naturally and continuously. This discharged foam can be collected with a suitable tray or the like. This foam is instantly cooled and solidified, and powdered boron atomide can be produced by appropriately crushing the solidified foam as desired.

As described above, the liquid in the sieve heating container becomes a foam and is discharged outside the heating container, so the liquid in the heating container decreases to the next level, and the liquid level is decreasing. Therefore,
The liquid in the low-temperature heating container is visually supplemented into the still-temperature heating container in accordance with the amount of decrease described above.

Also, as time passes, the 1f in both 710ffi containers mentioned above! The L-shaped bodies are both reduced to the next halberd.Therefore,
Boric acid (powder) is replenished into the low-temperature heating container at appropriate intervals (or minutes), thereby producing boron oxide continuously.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

The drawing shows one embodiment of the present invention, 1 is a low temperature heating container,
The heating container 1 is made of stainless steel, ceramic, or other heat-resistant material and has a cylindrical shape with a desired diameter and height. In this case, the material, size, shape, etc. of the container 1 can be changed arbitrarily. Reference numeral 2 denotes a lid that covers the upper end of the opening of the container 1, and a hopper 3 for supplying raw materials and an exhaust (steam) hole 4 are provided in the overhanging portion of the lid 2.

In the embodiment, as described above, the container 2 is placed in the lodging of the valley 61, but the lid 2 is not provided, and the container 1 is placed in the upper part 4 above the opening of the container 1.
It doesn't matter if it's Y open.

Reference numeral 5 denotes a stirrer rotated by Tanabata 6. The stirrer 5 is located at the center of a circle of the container, and the stirrer 5 is provided as desired. . Reference numeral 7 denotes a heater such as a burner or an electric heater, and the heaters 7 are arranged in an excessively distributed manner so as to heat the entire side surface and bottom surface of the heating container 1.

Although not shown in the drawings, a temperature sensor is disposed at an appropriate location in the low-temperature heating container 1, and the temperature of the liquid in one container is known by the temperature sensor, so that the amount of heat in the heater 7 can be controlled. It's also beautiful.

Reference numeral 8 denotes a high-temperature heating container, and the container 8 is connected to the low-temperature heating container 1 through an infusion channel 9, and is disposed so as to provide mutual fluid flow with the low-temperature heating container 1 due to a difference in liquid level. It is provided in contact with the side portion of the low-temperature heating container 1, and the bottom side surface of the low-temperature heating container 1 and the bottom center of the high-temperature heating container 8 are connected by an infusion channel 9 made of a heat-resistant pipe. In this case, the phase liquid path 9 may be covered with a heat insulating material to keep it warm, or a heater may be provided at an appropriate location to heat it at an appropriate temperature.

The high-temperature heating container 8 is made of stainless steel, ceramic, or other heat-resistant material and has a cylindrical shape with a desired rotation and length. As with the low-temperature heating container 1, the material, size, shape, etc. of this container 8 can be changed as desired. Reference numeral 10 denotes an outlet provided on the side circumference near the upper end of the opening of the container 8. The outlet 10 in the embodiment is a concave cutout in a part of the wall surface at the upper end of the container 8, and a gutter body is fixed in the cutout. It is composed of In the embodiment, one outlet 10 is provided, but the number of outlets 10 can be increased arbitrarily, and the container 8 may be arranged with no outlet 10 at a slight inclination. However, it is also possible to configure the container 8 so that the foam-like material described later is discharged from a lower part of the upper edge of the container 8.

Reference numeral 11 indicates a saucer body disposed below the outlet 10, and reference numeral 12 indicates a heater such as a burner or an electric heater. It would be a shame if they were allocated and placed excessively.

Although not shown in the drawings, a temperature sensor may be provided in a corresponding portion of the container 1 to detect the temperature of the liquid in the container 8 in the same way as the container 1 described above.

In addition, in the embodiment, one low temperature heating container 1 is provided with one temperature heating container 8, but a plurality of temperature heating devices 8 are provided, and one low temperature heating container 8 is provided with one temperature heating container 8. 1 through the infusion channel 9. in this way,
When several rotary temperature heating containers 8 are provided, it is preferable that the volume of the high temperature heating container 8 is smaller than the volume of the low temperature heating container 1.

Next, a method for producing boron fermentation will be explained. Both containers 1, 8
is heated by heaters 7 and 12 (the heating temperature will be described later). Then, as shown in Figure 3 (a), the raw material boric acid A
(in powder form, water-containing powder 43.7, 96) in a low-temperature heating container 1
Put an appropriate amount inside. Therefore, the porcelain [A] in the container 1 is heated, and as time passes, the temperature increases and dehydration begins. The RA then dissolves into liquid B at a temperature of about 150°C, as shown in Figure 3 (b).

The state in which boric acid (powder) is melted in a bath and transformed into boron modified material B continues over a period of 150°C to 200°C during the summer. Therefore, the temperature of the liquid B in the container 1 is 150°C to 20°C.
Heating is continued by adjusting the heat of the heater 7 so as to maintain the temperature within a range of about 0°C.

When the boric acid liquid B becomes hostile as described above, the boric acid liquid B blocks the liquid path 9 and is introduced into the heating container 8. Then, when the liquid levels of the liquid B in the still-temperature heating container 8 and the liquid B in the low-temperature heating container 8 become the same level, the introduction of the liquid B is temporarily stopped.

10,000, the liquid material B introduced into the high-temperature heating container 8 is further heated in the container at a high temperature, and as dehydration progresses, it becomes viscous, as shown in Figure 3 (c). Then, it becomes a somewhat viscous liquid C. Next, the dehydration progresses further, and when the water content reaches 90% or more, the water content is less than LUX, and the liquid temperature reaches 240°C or more (however, a slight deviation occurs depending on the heating rate), the liquid state The body C swells into a highly viscous foam as shown in Figure 3) and blows up to the next level. The temperature of the liquid C in the container 8 is increased to 240°C to 500°C.
Heating is continued by adding heat from the heater 12 so as to maintain the temperature at 500°C, preferably in the range of 250°C to 450°C. In this case, if the temperature of liquid C becomes too high and exceeds its melting point (577°C), the foam disappears and it becomes like water a'Pg molten glass as shown in Figure 3 (e). This becomes a molten body E.

Therefore, as mentioned above, the temperature of the liquid in the container 8 was approximately 40°C.
By maintaining the temperature at about ~450°C, the liquid C in the container 8 gradually becomes foamy and rises above the height of the container 8.
As shown in Figure 1'F/, the foam also oozes out from the outlet 10, naturally and continuously drains out of the container 8, hangs down, and is captured by the tray body 11. It is collected to obtain foamy boron oxide.

The water content of boron oxide produced by the above process is 10% to 2.
%, and the degree of water content can be adjusted arbitrarily by adjusting the temperature of liquid C in the range of about 240°C to 500°C (however, depending on the heating rate, there may be a difference of 1,000°). occur).

Then, the collected foamy substance is left to cool and solidify at the time of R4, and by appropriately crushing it, powdered boron oxide, which is used for new cars, is obtained.

On the other hand, as described above, the liquid in the high-temperature heating container 8 becomes foamy and is sequentially discharged outside the container 8, and the liquid in the high-temperature heating container 8 decreases rapidly, causing the liquid level to drop. Then, the liquid B in the low-temperature heating container 1 is automatically supplemented into the container 8 in response to this reduction lid.

Then, replenish 1 ton (a small amount) of the raw material sulfur into the low-temperature heating container 1 at appropriate intervals or hours, or replenish a very small amount (the same amount as y when the liquid C becomes foamy). ) is continuously replenished into the low-temperature heating container l, thereby continuously obtaining boron oxide.

Note that the replenishment of the raw material Hou mA may be performed automatically.

(Effects) The method of the present invention is as explained above, and according to the present invention, the following effects can be expected.

(α) Since boric acid is collected by being discharged from the container in a foam form without being melted in a channel, the production time can be reduced compared to conventional methods.

tb+ Since high-temperature heating unlike the conventional method is not required, the material of the heating container can be easily selected, and fuel consumption can be greatly reduced.

(C) Since the foam can be naturally discharged out of the container, the product can be easily and quickly taken out.

(Since it is collected by dl foam, it includes ii 90
It can be efficiently produced by using boron oxide of any quality within the range of about % to 98% (water content i io x to about 29%).

(eJ low-temperature heater Pre-caulked boric acid in the container is heated to make it a liquid, and this liquid is automatically replenished into the high-temperature heating container according to the amount of decrease in the liquid in the high-temperature heating container. Boron oxide can be continuously produced from

[Brief explanation of drawings]

Figure 77 is a schematic longitudinal sectional side view showing an example of the method for producing boron oxide according to the present invention, and Figure 12 is a schematic plan view as well.
Figure Ij-(E) changes due to heating dehydration of boric acid in the container.
FIG. 1...Low temperature heating container, 8...High temperature heating container, 7゜12...Heater, 9...
Infusion route, A...boric acid, B...boric acid liquid, C...somewhat viscous boric acid liquid,
D...Boric acid foam. Patent applicant: Ruscut Chemical Co., Ltd. (A)
(b) (c) (d) (e) Procedural amendment March 1986 / ρ Japan Special Fraud Office Director General Uga Enbe 1, Indication Patent 1 @ 61-25356 No. 2, Name of Invention Oxidation Manufacturing method for Houki 3, relationship with the case of the person making the amendment Patent applicant address: 1679-6, Kag, Yuki City, Ibaraki Prefecture, Representative: Yoshio Oyama, '1゜4, Agent: 5, Amendment order Date of publication 6, Subject of amendment (1) Detailed explanation of the invention in the specification 7, Contents of amendment (1) "Liquid volume" in the third line of the inconsistent page of the specification is amended to "liquid temperature" do. (2) "Memeyu" in line 6 of page 14 of the specification is corrected to "meshiyu".

Claims (1)

[Claims] (1) a low-temperature heating container, connected to the heating container via an infusion route;
It is equipped with a low-temperature heating container and a high-temperature heating container arranged so that liquid can flow between them due to a difference in liquid level, and boric acid is heated in the low-temperature heating container while maintaining the temperature at which the boric acid turns into a liquid. A boric acid liquid that changes into a liquid state by heating and is introduced into a high-temperature heating container is heated in a high-temperature heating container while maintaining a temperature at which the boric acid liquid swells into a foam, and the heating changes it into a foam. A method for producing boron oxide, which comprises sequentially discharging and collecting the boric acid foam that swells from the upper side of a high-temperature heating container to the outside of the container.