JP5954492B2 - Silicon oxide production apparatus and method - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a method and an apparatus for producing silicon oxide which are suitably used for packaging film vapor deposition, a lithium ion secondary battery negative electrode active material and the like.

  Conventionally, as a method for producing silicon oxide powder, a raw material mixture composed of silicon dioxide-based oxide powder is heat-treated in a reduced pressure non-oxidizing atmosphere to generate silicon oxide vapor, and the silicon oxide vapor is condensed in the gas phase. , A method of continuously producing fine amorphous silicon oxide powder of 0.1 μm or less (Patent Document 1: Japanese Patent Laid-Open No. 63-103815), and raw material silicon is heated and evaporated to roughen the surface structure A method of vapor deposition on the surface of a substrate (Patent Document 2: JP-A-9-110412) is known. Also, a mixed raw material powder containing silicon dioxide is supplied into the reaction furnace, silicon oxide gas is generated and deposited on the cooled substrate surface, and then this silicon oxide precipitate is continuously recovered (Patent Document 3: JP 2001-220123 A).

  However, although the above-mentioned method disclosed in JP-A-63-103815 can be continuously produced, the generated SiO powder is fine, and high-purity silicon oxide powder is obtained by an oxidation reaction when taken out to the atmosphere. There is a problem that can not be manufactured. On the other hand, the method described in JP-A-9-110412 is premised on a batch method, although it can produce high-purity silicon oxide. Therefore, mass production is difficult, and as a result, only expensive silicon oxide powder can be produced. Although the method described in JP-A-2001-220123 can continuously recover high-purity silicon oxide powder, since the silicon oxide is hard, the blade of the scraping device, which is a recovery mechanism, is easily worn, There was a problem that it could not be used.

JP-A 63-103815 JP-A-9-110412 JP 2001-220123 A

  This invention is made | formed in view of the said situation, and provides the manufacturing method and manufacturing apparatus of a silicon oxide which can manufacture highly purified silicon oxide continuously efficiently and stably over a long period of time.

  As a result of intensive studies to achieve the above object, the inventors of the present invention have disclosed a method for producing silicon oxide in which a silicon oxide gas is generated and deposited on the substrate. Using a manufacturing apparatus in which a deposition chamber and a collection chamber for depositing a deposition chamber and a preparation chamber in which a substrate for depositing a silicon oxide solid is disposed are connected via a gate valve, respectively, (1) a step of depositing silicon oxide on the surface of the substrate in the deposition chamber with the recovery chamber side gate valve and the preparation chamber side gate valve closed, and then (2) both gates. The valve is opened to move the substrate on which silicon oxide is deposited from the deposition chamber to the recovery chamber, and after moving the substrate disposed in the preparation chamber to the deposition chamber, the recovery chamber side gate valve and the preparation chamber side gate valve , Then (3 The substrate having silicon oxide deposited thereon or the deposited silicon oxide and the substrate are removed from the recovery chamber and another substrate is disposed in the preparation chamber, and the substrate moved from the preparation chamber following the step (2). It is found that high purity silicon oxide can be continuously produced efficiently and stably for a long period of time by repeating the above steps (1) to (3) using That led to

Accordingly, the present invention provides the following inventions.
[1]. A reaction chamber for reacting mixed raw material powder containing silicon dioxide powder to generate silicon oxide gas; a raw material supply mechanism for supplying the mixed raw material powder into the reaction chamber; and the silicon oxide gas as silicon oxide solid on the surface thereof Two or more substrates to be deposited, a deposition chamber for depositing a silicon oxide solid on the substrate, a transport pipe for transporting the silicon oxide gas from the reaction chamber to the deposition chamber, a recovery chamber, and a silicon oxide solid A deposition chamber and a recovery chamber are connected via a recovery chamber side gate valve, and the deposition chamber and the preparation chamber are connected via a preparation chamber side gate valve. An apparatus for producing silicon oxide.
[2]. [1] A mixed raw material powder containing silicon dioxide powder is supplied into a reaction chamber using the apparatus described in [1], and heated to 1,200 to 1,600 ° C. under normal pressure or reduced pressure in this reaction chamber. And (1) depositing silicon oxide on the surface of the substrate in the deposition chamber with the collection chamber side gate valve and the preparation chamber side gate valve closed, through a transfer tube maintained at the same temperature as the reaction chamber Next, (2) both gate valves are opened to move the substrate on which silicon oxide has been deposited from the deposition chamber to the collection chamber, and after moving the substrate disposed in the preparation chamber to the deposition chamber, the collection chamber side gate A step of closing the valve and the preparation chamber side gate valve, and then (3) a step of removing the silicon oxide-deposited substrate or the deposited silicon oxide and the substrate from the recovery chamber and disposing another substrate in the preparation chamber. Following the step (2) above, Perform the above (1) step using a substrate that has moved from the chamber, (1) to (3) The method for producing a silicon oxide-repeating process.
[3]. [2] The production method according to [2], wherein the mixed raw material powder is a mixture of silicon dioxide and metal silicon powder.
[4]. The method according to [2] or [3], wherein the temperature of the substrate in the deposition chamber is 200 to 1,000 ° C.
[5]. Furthermore, the obtained silicon oxide solid is pulverized, and the obtained silicon oxide powder has an average particle diameter of 0.01 to 30 μm and a BET specific surface area of 0.5 to 30 m ² / g [2] to [ [4] The production method according to any one of [4].
[6]. The production method according to any one of [2] to [5], wherein the silicon oxide is used for film deposition for packaging.
[7]. The production method according to any one of [2] to [5], wherein the silicon oxide is used for a negative electrode active material for a lithium ion secondary battery.

  According to the present invention, it is possible to continuously produce high-purity silicon oxide that is efficient and stable for a long period of time.

It is a schematic sectional drawing which shows one Example of this invention. It is a schematic sectional drawing which shows the state of the aspect of one Example of this invention. 2 is a schematic cross-sectional view of an apparatus used in Comparative Example 1. FIG.

Hereinafter, the present invention will be described in more detail.
In the production method of the present invention, mixed raw material powder containing silicon dioxide powder is supplied into a reaction chamber and heated to 1,200 to 1,600 ° C. under normal pressure or reduced pressure to generate silicon oxide gas. And (1) depositing silicon oxide on the surface of the substrate in the deposition chamber with the recovery chamber side gate valve and the preparation chamber side gate valve closed, through a transfer tube maintained at the same temperature or higher as the reaction chamber, (2) Open both gate valves to move the substrate on which the silicon oxide is deposited from the deposition chamber to the collection chamber, and move the substrate disposed in the preparation chamber to the deposition chamber; A step of closing the preparation chamber side gate valve, and then (3) a step of removing the silicon oxide deposited substrate or the deposited silicon oxide and the substrate from the recovery chamber and disposing another substrate in the preparation chamber, (2) Following the process, preparation Perform the above (1) step using the moved substrate from a method for producing a silicon oxide repeating the above steps (1) to (3).

As the mixed raw material powder containing silicon dioxide powder, a mixture of silicon dioxide powder and powder that reduces the powder is used. Specific examples of the reducing powder include metal silicon compounds and carbon-containing powders, and metal silicon powder is preferable from the viewpoint of increasing reactivity and increasing yield. In the case of silicon dioxide powder and metal silicon powder, the reaction proceeds according to the following reaction scheme.
Si (s) + SiO ₂ (s) → 2SiO (g)

The average particle diameter of the silicon dioxide powder used for this invention is 0.1 micrometer or less, and is 0.005-0.1 micrometer normally, Preferably it is 0.005-0.08 micrometer. The average particle size of the metal silicon powder is 30 μm or less, and is usually 0.05 to 30 μm, preferably 0.1 to 20 μm. When the average particle diameter of the silicon dioxide powder is larger than 0.1 μm, or the average particle diameter of the metal silicon powder is larger than 30 μm, the reactivity is lowered and the productivity may be lowered. In the present invention, the average particle diameter can be represented by the cumulative weight average value D ₅₀ in the particle size distribution measurement by the laser light diffraction method.

  In the present invention, the mixed raw material powder is heated and held in the reaction chamber at a temperature of 1,200 to 1,600 ° C., preferably 1,300 to 1,500 ° C., to generate silicon oxide gas. If the reaction temperature is less than 1,200 ° C, the reaction is difficult to proceed and the productivity is lowered. There is.

  On the other hand, the atmosphere in the furnace (reaction chamber) is performed under normal pressure or reduced pressure (preferably 1,000 Pa or less). It is preferable to carry out under reduced pressure at which silicon oxide is easily generated as a gas. The inside of the furnace may be in an inert gas. Examples of the inert gas include argon gas and helium gas.

  In the reaction chamber, the mixed raw material powder is supplied at appropriate intervals or continuously by a raw material supply mechanism, and the reaction is continuously performed. Examples of the raw material supply mechanism include continuous supply using a screw feeder or the like, intermittent supply using an intermediate hopper having upper and lower dampers, and combinations thereof.

  The silicon oxide gas generated in the reaction chamber is continuously supplied to the deposition chamber via the transport pipe. The transfer tube is maintained at the same temperature as the reaction chamber. When the temperature of the transfer pipe is lower than the reaction chamber, the silicon oxide gas is deposited on and adhered to the inner wall of the transfer pipe, causing troubles in operation and preventing stable operation. On the other hand, heating to a temperature significantly exceeding the reaction chamber causes an increase in power cost and does not produce an effect, and therefore, the same temperature as the reaction chamber to the reaction chamber temperature + 200 ° C. is appropriate.

(1) Step of depositing silicon oxide on the substrate surface in the deposition chamber with the recovery chamber side gate valve and the preparation chamber side gate valve closed. When introducing silicon oxide gas into the deposition chamber in which the substrate is disposed, The recovery chamber side gate valve between the deposition chamber and the recovery chamber and the preparation chamber side gate valve between the deposition chamber and the preparation chamber are closed so that the gas does not flow into the preparation chamber or the recovery chamber. It is necessary. A substrate for depositing silicon oxide is disposed in the deposition chamber, and the silicon oxide gas introduced into the deposition chamber is brought into contact with the substrate to be cooled, whereby bulk silicon oxide (solid) is formed on the surface of the substrate. ). The temperature of the substrate in the deposition chamber (precipitation temperature) is preferably maintained at 200 to 1,000 ° C, more preferably 300 to 900 ° C, and even more preferably 300 to 800 ° C. If the temperature is higher than 1,000 ° C., silicon oxide may be difficult to precipitate. If the temperature is lower than 200 ° C., the obtained silicon oxide may become fine powder and may have too strong activity. The substrate temperature is measured by measuring the back side of the surface directly exposed to silicon oxide vapor. The measurement can be performed by a method in which the thermocouple is brought into contact with the substrate, a method in which the thermocouple is measured in a non-contact manner, and the temperature in the present invention is a value measured by a method in which the thermocouple is brought into contact with the substrate.

(2) Open both gate valves to move the substrate on which the silicon oxide is deposited from the deposition chamber to the collection chamber, and move the substrate disposed in the preparation chamber to the deposition chamber; Step of closing the preparation chamber side gate valve At this time, both gate valves are opened simultaneously, and the substrate on which silicon oxide is deposited from the deposition chamber to the recovery chamber and the substrate from the preparation chamber to the deposition chamber are simultaneously moved. Both gate valves may be closed at the same time, or the recovery chamber side gate valve is opened, the substrate on which silicon oxide is deposited from the deposition chamber to the recovery chamber is moved, and after the recovery chamber side gate valve is closed, The gate valve on the preparation chamber side may be opened to move the substrate from the preparation chamber to the deposition chamber, and the gate valve on the preparation chamber side may be closed, but the former is preferably performed simultaneously.

  In the recovery chamber in which the substrate in the deposition chamber has moved, the amount of heat brought into the substrate by the silicon oxide gas is eliminated, and the temperature of the substrate decreases. At this time, the substrate may be forcibly cooled by a cooling means such as air cooling or water cooling. The temperature of the substrate is preferably lowered to 500 ° C. or lower, more preferably 300 ° C. or lower, in which silicon oxide deposited on the substrate is stable in the air. By stopping the introduction of the silicon oxide vapor into the deposition chamber and cooling the substrate, the deposited silicon oxide is easily separated from the substrate surface.

  The type of the substrate is not particularly limited, but those having heat resistance at the deposition temperature and corrosion resistance to the silicon oxide gas, specifically, metal materials and ceramic materials are preferable. Further, a material having a large difference in linear expansion coefficient from silicon oxide is more preferable because the deposited silicon oxide is easily peeled off from the surface of the substrate due to a difference in thermal contraction between the substrate and the silicon oxide precipitate and can be easily recovered. Specifically, a metal material is preferable, and stainless steel (SUS), a nickel alloy, a titanium alloy, or the like is preferably used in terms of workability.

  A silicon oxide gas is supplied to the deposition chamber in which the substrate disposed in the preparation chamber has moved in the same manner as described above, and the step (1) is performed using the substrate moved from the preparation chamber following the step (2). A lump of silicon oxide is deposited on the surface of the substrate in the deposition chamber, and it becomes possible to continuously supply silicon oxide gas and to deposit silicon oxide continuously.

(3) A step in which the substrate on which silicon oxide is deposited or the deposited silicon oxide and substrate is taken out from the collection chamber and another substrate is arranged in the preparation chamber. The collection chamber is isolated from the deposition chamber by a collection chamber side gate valve. Therefore, the substrate on which silicon oxide is deposited or the deposited silicon oxide and substrate can be taken out from the recovery chamber without stopping the operation of the apparatus. The substrate in the collection chamber is taken out from the collection chamber in order to move the next substrate from the deposition chamber. Similarly, since the preparation chamber is isolated from the deposition chamber by the preparation chamber side gate valve, another substrate can be arranged in the preparation chamber without stopping the operation. In order to keep the deposition chamber temperature during the movement of the substrate within a predetermined range, the substrate disposed in the preparation chamber may be preheated by a heating mechanism such as a heater.

  When the deposition chamber is in a reduced pressure atmosphere, it is necessary to decompress the preparation chamber and the recovery chamber to make the pressure equal to the deposition chamber before opening the gate valve. Before the next substrate is placed in the preparation chamber, the preparation chamber and the recovery chamber must be restored to atmospheric pressure. Even in this case, the substrate can be taken out and arranged without stopping the operation and without stopping the introduction of the silicon oxide gas into the deposition chamber.

  In the present invention, following the step (2), the step (1) is performed using the substrate moved from the preparation chamber, and the steps (1) to (3) are repeated. Thereby, it is possible to take out the substrate on which the silicon oxide is deposited or the deposited silicon oxide and the substrate and to dispose the next substrate in the preparation chamber without stopping the operation. In parallel with the deposition of silicon oxide in the deposition chamber, the progress of exfoliation of silicon oxide in the recovery chamber, the removal of the substrate on which silicon oxide has been deposited from the recovery chamber, and the placement of a new substrate in the preparation chamber. The deposition can be carried out sequentially or continuously, and silicon oxide can be continuously produced efficiently. For this reason, two or more substrates are required, three or more substrates may be used, and the substrate after the deposited silicon oxide is recovered may be used as the next substrate.

  The method for moving the substrate is not particularly limited, and examples thereof include a belt conveyor and a roller conveyor. The interval for moving the substrate is appropriately selected depending on the feed rate of the raw material, the cooling rate of the substrate, and the like, but preferably 1 to 8 hours.

  The purity of silicon oxide in silicon oxide is 99.9 to 99.95% by mass, and a high-purity product can be obtained.

The obtained bulk silicon oxide solid can be made into silicon oxide powder by using an appropriate pulverizer and classifier. For example, a silicon oxide powder having an average particle size of 0.01 to 30 μm and a BET specific surface area of 0.5 to 30 m ² / g can be obtained. Such silicon oxide powder is suitable for film deposition for packaging, negative electrode active material for lithium ion secondary battery, and the like.

  As an apparatus used in the above method, for example, as shown in FIG. 1, a reaction chamber in which a mixed raw material powder containing silicon dioxide powder is reacted to generate silicon oxide gas, and the mixed raw material powder is supplied into the reaction chamber. A raw material supply mechanism, two or more substrates on which the silicon oxide gas is deposited as a silicon oxide solid, a deposition chamber in which the silicon oxide solid is deposited on the substrate, and the silicon oxide gas is deposited from the reaction chamber into the deposition chamber. A transport pipe for transporting to the chamber, a recovery chamber, and a preparation chamber for disposing a substrate on which the silicon oxide solid is deposited, the deposition chamber and the recovery chamber being connected via a recovery chamber side gate valve, Examples include a continuous production apparatus for silicon oxide in which a chamber and a preparation chamber are connected via a preparation chamber side gate valve.

An example of the apparatus will be described in more detail.
The reaction furnace 1 has a reaction chamber 2 therein. A reaction chamber heater 3 is provided in the reaction chamber 2, a raw material supply mechanism 5 is connected to the reaction chamber 2, and the reaction chamber 2 is connected to a deposition chamber 7 through a transport pipe 6. The transfer tube 6 includes a transfer tube heater 8, and a substrate 9 a is disposed in the deposition chamber 7. The deposition chamber 7 is connected to a recovery chamber 11 via a recovery chamber side gate valve 13a, and the deposition chamber 7 is connected to a preparation chamber 15 via a preparation chamber side gate valve 13b. 9b is arranged, and a preheating mechanism 16 and a preparation chamber door 17 are provided. The collection chamber 11 includes a cooling mechanism 12 and a collection chamber door 14 is installed. 18a to 18d are vacuum pumps, which are connected to the deposition chamber 7, the recovery chamber 11, the preparation chamber 15, and the raw material supply mechanism 5, respectively.

  The reaction chamber 2 is heated to 1,200 to 1,600 ° C. by the reaction chamber heater 3. A mixed raw material powder 4 containing silicon dioxide powder is continuously or intermittently supplied to the reaction chamber 2 by a raw material supply mechanism 5. The silicon oxide gas generated in the reaction chamber 2 is transported to the deposition chamber 7 through the transport pipe 6. The transfer tube 6 is held above the temperature of the reaction chamber 2 by a transfer tube heater 8. The deposition chamber 7 is provided with a substrate 9 a and is kept at a predetermined temperature by a deposition chamber heater 10. Both the recovery chamber side gate valve 13a and the preparation chamber side gate valve 13b are closed, and the deposition chamber 7 is isolated from the recovery chamber 11 and the preparation chamber 15, and silicon oxide gas is introduced into the precipitation chamber 7 for a desired time. Then, silicon oxide is deposited on the surface of the substrate 9a. Since the preparatory chamber 15 is set to an appropriate temperature by the preheating mechanism 16 and is isolated from the deposition chamber 7 by the preparatory chamber side gate valve 13b, the substrate 9b can be appropriately inserted from the preparatory chamber door 17 during continuous operation.

  Thereafter, both gate valves are opened to move the substrate 9a of the deposition chamber 7 to the recovery chamber 11, and after moving the substrate 9b disposed in the preparation chamber 15 to the deposition chamber 7, both gate valves are closed, The collection chamber 11 and the deposition chamber 7 are isolated from each other by the collection chamber side gate valve 13a, and the deposition chamber 7 and the preparation chamber 15 are separated from each other by the preparation chamber side gate valve 13b.

  The collection chamber 11 is cooled to a predetermined temperature by the cooling mechanism 12. Since the collection chamber 11 is isolated from the deposition chamber 7 by the collection chamber side gate valve 13a, the substrate on which silicon oxide is deposited, or the deposited silicon oxide and the substrate 9a can be taken out from the collection chamber door 14 during continuous operation. it can. In parallel with this, a substrate 9b moved from the preparation chamber is disposed in the deposition chamber 7, and silicon oxide gas is introduced into the deposition chamber 7 for a desired time to deposit silicon oxide on the surface of the substrate 9b. The preparatory chamber 15 is kept at an appropriate temperature by the preheating mechanism 16, and is isolated from the deposition chamber 7 by the preparatory chamber side gate valve 13b. A new substrate 9c can be appropriately inserted from the preparatory chamber door 17 during continuous operation. Note that the substrate 9c may be the substrate 9a after the deposited silicon oxide is collected. The collection chamber 11, the deposition chamber 7, and the preparation chamber 15 may be decompressed by a vacuum pump.

  According to the manufacturing method and apparatus described above, silicon oxide can be manufactured continuously and stably at low cost by replacing the substrate.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.

[Example 1]
Silicon oxide was manufactured using the continuous manufacturing apparatus shown in FIG. The raw material was a silicon dioxide powder (average particle size 0.02 μm, BET specific surface area 200 m ² / g) and metal silicon powder (average particle size 10 μm, BET specific surface area 3 m ² / g) in an equimolar mole ratio. 20 kg of mixed raw material powder was initially charged in the reaction chamber 2 (volume 0.5 m ³ ) in the reaction furnace 1. Next, with the recovery chamber side gate valve 13a and the preparation chamber side gate valve 13b being closed, the inside of the furnace is depressurized to 10 Pa or less using the vacuum pump 18a, and then the reaction chamber heater 3 is energized. The temperature was kept at 1,400 ° C. On the other hand, the transfer tube heater 8 is energized, the transfer tube 6 is held at 1,400 ° C., the deposition chamber heater 10 is energized, and the SUS substrate 9a previously placed in the deposition chamber 7 is heated to 650 ° C. Retained. From the pressure increase in the reaction chamber, it was confirmed that silicon oxide gas was generated. Next, the raw material supply mechanism 5 was operated, and the mixed raw material powder was continuously supplied at a rate of 2 kg / h. Since the reaction chamber pressure was stable after that, it was confirmed that the reaction was continuous. In the meantime, the base body 9b was put into the preparation chamber 15 from the preparation chamber door 17 and preheated to 300 ° C. by the preheating mechanism 16 (heater). Silicon oxide gas was introduced into the deposition chamber 7, and a silicon oxide solid was deposited on the surface of the substrate 9 a in the deposition chamber 7. After operating for 4 hours after the reaction chamber reaches 1,400 ° C., the recovery chamber 11 and the preparation chamber 15 are depressurized by the vacuum pumps 18b and 18c until the pressure is almost the same as that of the precipitation chamber 7, and the recovery chamber side gate valve 13a, The preparation chamber side gate valve 13b is opened, and the substrate 9a is moved from the deposition chamber 7 to the collection chamber 11, and at the same time, the substrate 9b is moved from the preparation chamber 15 to the precipitation chamber 7, and the collection chamber side gate valve 13a and the preparation chamber side gate valve are moved. 13b was closed again. FIG. 2 shows a state in which the substrate 9a is moved from the deposition chamber 7 to the recovery chamber 11, the substrate 9b is moved from the preparation chamber 15 to the deposition chamber 7, and the next substrate 9c is prepared. The substrate 9b was heated by the silicon oxide gas and the deposition chamber heater 10, and the temperature of the substrate 9b was stabilized at 650 ° C. after 5 minutes. On the other hand, the base body 9a loses the amount of heat brought in by the silicon oxide gas, and is further cooled by the cooling mechanism 12, and the temperature of the base body 9a gradually decreases. After 2 hours, the temperature of the base body 9a dropped to 200 ° C., so the recovery chamber 11 was restored to atmospheric pressure, and the base body 9a was taken out from the recovery chamber door. The silicon oxide adhering to the surface of the substrate 9a could be easily peeled off due to the difference in thermal shrinkage and recovered. At the same time, the preparatory chamber 15 was also restored to atmospheric pressure, and the next base 9c was put into the preparatory chamber 15 from the preparatory chamber door 17. As a result of continuously performing the above operation for 600 hours, silicon oxide was recovered at 1.9 kg / h (yield = 95%). The powder having an average particle diameter D ₅₀ of 5 μm obtained by pulverizing the silicon oxide thus obtained with a ball mill is an amorphous powder having a BET specific surface area of 8 m ² / g and a purity of 99.9% by mass or more. there were. In addition, it was confirmed that there was no particular problem by observing the inside of the apparatus after the operation was completed.

[Comparative Example 1]
Silicon oxide powder was manufactured using the continuous manufacturing apparatus shown by FIG. 1 (FIG. 3) of Unexamined-Japanese-Patent No. 2001-220123. The raw material was the same mixed powder of silicon dioxide powder and metal silicon powder as in the example, and 20 kg of mixed raw material powder was initially charged in the reaction chamber (volume 0.5 m ³ ) in the reaction furnace as in Example 1. . Next, after reducing the pressure in the furnace to 10 Pa or less using a vacuum pump, the heater was energized, and the temperature was raised to 1,400 ° C., which was the same as in Example 1. On the other hand, the conveyance pipe was heated and held at 1,400 ° C., water was introduced into the refrigerant introduction pipe, and the SUS substrate was cooled. Next, the feeder was operated, and the mixed raw material powder was continuously supplied at a rate of 2 kg / h to carry out a continuous reaction. The silicon oxide deposited on the substrate was continuously scraped by a scraper having a tungsten carbide blade, which is a super hard material, and recovered in a recovery chamber. When the above operation was continuously performed for 120 hours, silicon oxide was recovered at 1.9 kg / h (yield = 95%). The powder having an average particle diameter D ₅₀ of 5 μm obtained by pulverizing the silicon oxide thus obtained with a ball mill is an amorphous powder having a BET specific surface area of 8 m ² / g and a purity of 99.9% by mass or more. There was a trace amount of tungsten as an impurity element. After that, the recovery rate began to drop sharply after 300 hours of continuous operation, and the operation was terminated. When the inside of the apparatus was observed, the blade at the tip of the scraper was worn and no more could be scraped off. It was in a state.

DESCRIPTION OF SYMBOLS 1 Reaction furnace 2 Reaction chamber 3 Reaction chamber heater 4 Mixed raw material powder 5 Raw material supply mechanism 6 Conveyance pipe 7 Deposition chamber 8 Conveyance pipe heater 9a, 9b, 9c Base | substrate 10 Deposition chamber heater 11 Collection chamber 12 Cooling mechanism 13a Collection chamber side gate valve 13b Preparation chamber side gate valve 14 Recovery chamber door 15 Preparation chamber 16 Preheating mechanism 17 Preparation chamber doors 18a to 18d Vacuum pump 101 Reactor 102 Reaction chamber 103 Mixed raw material powder 104 Heater 105 Heat insulating material 106 Raw material supply mechanism 107 Replenishment hopper 108 Feeder 109 Raw material supply pipe 110 Conveyance pipe (conveyance line)
111 Deposition tank 112 Deposition chamber 113 Base 114 Refrigerant introduction pipe 115 Refrigerant discharge pipe 116 Scraping device (recovery mechanism)
117 Recovery pipe 118 Recovery tank 119 Vacuum pump 120 Vacuum pump 121 Vacuum pump

Claims (7)

  A reaction chamber for reacting mixed raw material powder containing silicon dioxide powder to generate silicon oxide gas; a raw material supply mechanism for supplying the mixed raw material powder into the reaction chamber; and the silicon oxide gas as silicon oxide solid on the surface thereof Two or more substrates to be deposited, a deposition chamber for depositing a silicon oxide solid on the substrate, a transport pipe for transporting the silicon oxide gas from the reaction chamber to the deposition chamber, a recovery chamber, and a silicon oxide solid A deposition chamber and a recovery chamber are connected via a recovery chamber side gate valve, and the deposition chamber and the preparation chamber are connected via a preparation chamber side gate valve. An apparatus for producing silicon oxide.   A mixed raw material powder containing silicon dioxide powder is supplied into a reaction chamber using the apparatus according to claim 1, and heated to 1,200 to 1,600 ° C. under normal pressure or reduced pressure in the reaction chamber to produce silicon oxide gas And (1) depositing silicon oxide on the surface of the substrate in the deposition chamber with the collection chamber side gate valve and the preparation chamber side gate valve closed, through a transfer tube maintained at the same temperature as the reaction chamber Next, (2) both gate valves are opened to move the substrate on which silicon oxide has been deposited from the deposition chamber to the collection chamber, and after moving the substrate disposed in the preparation chamber to the deposition chamber, the collection chamber side gate A step of closing the valve and the preparation chamber side gate valve, and then (3) a step of removing the silicon oxide-deposited substrate or the deposited silicon oxide and the substrate from the recovery chamber and disposing another substrate in the preparation chamber. Continued from step (2) above Perform the above (1) step using a substrate that has moved from the preparation chamber, (1) to (3) The method for producing a silicon oxide-repeating process.   The method according to claim 2, wherein the mixed raw material powder is a mixture of silicon dioxide and metal silicon powder.   The method according to claim 2 or 3, wherein the temperature of the substrate in the deposition chamber is 200 to 1,000 ° C. Further, the obtained silicon oxide solid is pulverized, and the silicon oxide powder obtained has an average particle size of 0.01 to 30 μm and a BET specific surface area of 0.5 to 30 m ² / g. The manufacturing method of any one of these.   The manufacturing method according to any one of claims 2 to 5, wherein the silicon oxide is for packaging film deposition.   The manufacturing method according to any one of claims 2 to 5, wherein the silicon oxide is used for a negative electrode active material for a lithium ion secondary battery.

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