CN115364509A

CN115364509A - Preparation device of silicon oxide

Info

Publication number: CN115364509A
Application number: CN202210124601.8A
Authority: CN
Inventors: 林煌伟; 杨瑜民; 许松林
Original assignee: Sino American Silicon Products Inc
Current assignee: Sino American Silicon Products Inc
Priority date: 2021-05-19
Filing date: 2022-02-10
Publication date: 2022-11-22
Also published as: JP7361825B2; TWI798699B; TW202247509A; JP2022179337A

Abstract

A preparation device of silicon oxide comprises a heating furnace, a heating device, a crucible, a precipitation box, an exhaust pipeline and an air extractor, wherein a heating furnace chamber formed by a heat insulating material in a surrounding way is arranged in the heating furnace; the heating device, the crucible and the precipitation box are arranged in the heating furnace chamber; the separation box is provided with an air inlet and an air outlet, the separation box comprises at least one partition plate and is arranged in the inner space of the separation box, at least one channel is formed by the at least one partition plate and the inner wall of the separation box, and the at least one channel is respectively communicated with the air inlet and the air outlet; the gas exhaust pipeline is provided with a first end and a second end, the first end is arranged at a position close to the upper opening of the crucible, and the second end is communicated with the gas inlet of the precipitation box; the air extracting device is communicated with the air outlet of the precipitation box.

Description

Preparation device of silicon oxide

Technical Field

The invention relates to a silicon oxide preparation device; in particular to a silicon oxide preparation device capable of improving the yield of silicon oxide.

Background

As a secondary battery, there are known a nickel-cadmium battery, a nickel-hydrogen battery, a lithium ion secondary battery, and the like, and the lithium ion secondary battery has characteristics of high energy density, high operating voltage, small memory effect, and rapid charging, and the like, compared with the nickel-cadmium battery or the nickel-hydrogen battery, and thus is widely used in electronic devices such as a tablet pc, a smart phone, a notebook pc, a game console, and the like.

In the reaction inside the lithium ion secondary battery, a potential difference between the positive electrode and the negative electrode is mainly produced by reciprocating lithium ions between the positive electrode and the negative electrode, and since a general lithium ion secondary battery mostly uses graphite as a negative electrode material and the energy density of the lithium ion secondary battery using such a negative electrode material is very low, in order to increase the energy density, various new negative electrode materials have been developed, in which a lithium ion secondary battery having a high voltage and a high energy density can be obtained by using silicon oxide as a negative electrode material of the lithium ion secondary battery.

The existing silicon oxide preparation device for preparing the cathode material of the lithium secondary battery generally comprises a raw material container, a heating device, a precipitation chamber and an air extractor, wherein powder containing silicon oxide is arranged in the raw material container, heated and gasified, and then the air extractor is used for extracting silicon oxide gas and enabling the silicon oxide gas to flow through the precipitation chamber so as to precipitate solid silicon oxide on the inner wall of the precipitation chamber.

Disclosure of Invention

In view of the above, an object of the present invention is to provide an apparatus for preparing silicon oxide, which can improve the yield of silicon oxide.

The silicon oxide preparation device comprises a heating furnace, a heating device, a crucible, a precipitation box, an exhaust pipeline and an air extractor, wherein the heating furnace is internally provided with a heating furnace chamber formed by a heat insulating material in a surrounding way; the heating device is arranged in the heating furnace cavity; the crucible is arranged in the heating furnace chamber and used for containing a solid raw material, the solid raw material comprises silicon dioxide and silicon, and the heating device heats the crucible to enable the solid raw material to form a gaseous silicon oxide; the crucible is provided with an upper opening; the separating box is arranged in the heating furnace chamber and is provided with an air inlet and an air outlet, the separating box comprises at least one partition plate and is arranged in the inner space of the separating box, at least one channel is formed by the at least one partition plate and the inner wall of the separating box, and the at least one channel is respectively communicated with the air inlet and the air outlet; the gas exhaust pipeline is provided with a first end and a second end, the first end is arranged at a position close to the upper opening of the crucible, and the second end is communicated with the gas inlet of the precipitation box; the air pumping device is communicated with the air outlet of the precipitation box; the gas-pumping device pumps the gaseous silicon oxide out of the crucible so that the gaseous silicon oxide is contacted with the inner wall of the precipitation box and the surface of the at least one partition plate to precipitate solid silicon oxide.

The invention has the effects that the contact area of the gaseous silicon oxide is increased and the airflow path of the gaseous silicon oxide is prolonged by the arrangement of the at least one partition plate, so that the yield of silicon oxide precipitation is improved.

Drawings

Fig. 1 is a schematic view of an apparatus for preparing silicon oxide according to a preferred embodiment of the present invention.

Fig. 2 is a schematic view of a part of the components of the above preferred embodiment.

FIG. 3A is a schematic view of the above-described cartridge according to the preferred embodiment.

FIG. 3B is a schematic view of the cartridge according to the preferred embodiment.

FIG. 4 is a schematic view of a cartridge according to another preferred embodiment of the present invention.

FIG. 5 is a schematic view of a cartridge according to another preferred embodiment of the present invention.

Fig. 6 is a schematic view of a part of the components of another preferred embodiment of the present invention.

Fig. 7 is a schematic view of a part of the components of another preferred embodiment of the present invention.

Fig. 8 is a schematic view of a part of the components of another preferred embodiment of the present invention.

Detailed Description

In order to more clearly illustrate the present invention, preferred embodiments will be described in detail below with reference to the accompanying drawings. Referring to fig. 1 to fig. 3A and 3B, an apparatus 1 for preparing silicon oxide according to a preferred embodiment of the present invention is shown, wherein the apparatus 1 comprises a heating furnace 10, a stage 20, a heating device, a crucible 40, a deposition box 50, an exhaust pipe 60 and an air-extracting device 70.

The heating furnace 10 has a heating furnace chamber R surrounded by a heat insulating material 12, the stage 20, the heating device and the crucible 40 are disposed in the heating furnace chamber R, the crucible 40 is disposed on the stage 20, the crucible 40 has an upper opening 40a, the crucible is configured to receive a solid raw material, the solid raw material includes silicon dioxide and silicon, the heating device includes a plurality of heaters 30 disposed at positions surrounding an outer sidewall of the crucible 40 and above the crucible 40, respectively, the heating device is configured to heat the crucible 40 to form a gaseous silicon oxide from the solid raw material, and in this embodiment, the heating device is configured to maintain an internal temperature of the heating furnace chamber R between 1300 degrees and 1350 degrees.

The elution box 50 is disposed between the heating furnace chamber R and the inner furnace wall 10a of the heating furnace 10, the elution box 50 is disposed at a position close to the heating device, and the temperature of the elution box 50 is controlled to be maintained between 200 and 600 degrees by adjusting the distance between the elution box 50 and the heating device. The precipitation box 50 has an air inlet 50a and an air outlet 50b, the precipitation box 50 includes a plurality of partitions disposed in the inner space of the precipitation box 50, the partitions include a plurality of transverse partitions 80, and the transverse partitions 80 intersect with an axis X between the air inlet 50a and the air outlet 50b, the transverse partitions 80 and the inner wall of the precipitation box 50 form a channel C, the channel C communicates with the air inlet 50a and the air outlet 50b, respectively, and the total length of the channel C is greater than a minimum distance between the air inlet 50a and the air outlet 50 b. In the present embodiment, the thermal conductivity of the plurality of spacers is greater than or equal to 16W/m.k, and the melting point is greater than 1200 degrees, for example, the plurality of spacers may be made of stainless steel or graphite, but not limited thereto. In addition, in the present embodiment, the number of the channels C is described as an example, and in other embodiments, more than one channel can be formed by the arrangement positions of the plurality of partition plates 80.

In addition, in the embodiment, the analysis box 50 is a hexahedron with a length and a width of 350mm and 300mm, respectively, the height H of the analysis box 50 is 350mm, and the height H of the analysis box 50 is the height of the analysis box 50 in the direction away from the heating furnace chamber R, wherein the height H of the analysis box 50 is 350mm so as to maintain the temperature of the analysis box 50 between 200 and 600 degrees. It should be noted that, with reference to fig. 3A and 3B, in the present embodiment, the precipitation box 50 includes a box body 52 and a box cover 54, the box body 52 has a left side plate 521, a right side plate 522, a top plate 523, a bottom plate 524 and a side opening 525, the top plate 523 has the air outlet 50B, the bottom plate 524 has the air inlet 50a, the box cover 54 is used to close the side opening 525, the plurality of transverse partition plates 80 are substantially parallel to each other and are respectively connected to the inner wall of the box body 52 and the box cover 54, wherein one of the transverse partition plates 80 connected to the inner wall of the box body 52 is arranged in a manner of being connected to the left side plate 521 and maintaining a distance from the right side plate 522, the other transverse partition plate 80 connected to the inner wall of the box body 52 is arranged in a manner of being connected to the right side plate 522 and maintaining a distance from the left side plate 521, when the box cover 54 closes the side opening, the transverse partition plate 80 connected to the inner wall 52 and the box cover 80 connected to the box cover 52 are arranged in a staggered manner, and the distance between the first transverse partition plate 80 and the left side plate 80 is 1 mm, and the distance between the first side plate 20mm and the first side plate 20mm, respectively between the first transverse partition plate 521 and the right side plate 20mm, and the distance between the first partition plate 20 mm. In addition to the above, the design that the plurality of transverse partition plates 80 are alternately disposed on the box body 52 and the box cover 54 can facilitate a user to take out the produced solid silicon oxide, in this embodiment, the first distance D1 is selected from 15mm to 25mm because the gas flowing speed in the box body 52 is fast and the reaction time is short when the first distance D1 is greater than 25mm, which easily causes a reduction in the yield of silicon oxide, and when the first distance D1 is less than 15mm, the channel C is easily blocked by the produced silicon oxide between the transverse partition plate 80 and the left side plate 521 or the right side plate 522, which causes a reduction in the yield; the first distance H1 is selected to be between 20mm and 50mm, so that the effect of taking out the solid silicon oxide by a user is facilitated.

Referring to fig. 1, the exhaust duct 60 has a first end 60a and a second end 60b, the first end 60a is disposed adjacent to the upper opening 40a of the crucible 40, the second end 60b is communicated with the gas inlet 50a of the precipitation box 50, and the gas-pumping device 70 is communicated with the gas outlet 50b of the precipitation box 50, so that the gas-pumping device 70 pumps the gaseous silicon oxide out of the crucible 40, so that the gaseous silicon oxide contacts with the inner wall of the precipitation box 50 and the surfaces of the plurality of transverse partitions 80 to precipitate the solid silicon oxide S shown in fig. 3A, and the arrangement of the plurality of transverse partitions 80 increases the contact area with the gaseous silicon oxide and prolongs the gas flow path of the gaseous silicon oxide, thereby increasing the yield of precipitated solid silicon oxide S. In this embodiment, the air extracting device is exemplified by a cyclone dust collector, and the gas silicon oxide can be separated out from the cyclone dust collector through the cyclone dust collector, so as to improve the collection rate of the solid silicon oxide.

Referring to fig. 2, it is further illustrated that, in the present embodiment, the apparatus 1 for preparing silicon oxide includes a mask 90, the mask 90 covers the upper opening 40a of the crucible 40, and the mask 90 has an opening 90a, the opening 90a is communicated with the first end 60a of the exhaust duct 60 and the inside of the crucible 40, and the flow area of the gaseous silicon oxide can be limited by the arrangement of the mask 90, so as to improve the collection rate of the solid silicon oxide S.

It should be noted that, in the present embodiment, the number of the partition plates is illustrated by taking a plurality of example, however, in practice, the number of the partition plates may also be a transverse partition plate 80 disposed in the inner space of the precipitation box 50 as shown in fig. 4, the transverse partition plate 80 is connected to the right side plate 522, a second distance D2 is provided between the transverse partition plate 80 and the left side plate 521, a second distance H2 is provided between the top of the transverse partition plate 80 and the top plate 523, a third distance H3 is provided between the bottom of the transverse partition plate 80 and the bottom plate 524, and the transverse partition plate intersects the axis X between the gas inlet 50a and the gas outlet 50b, so that the effects of increasing the contact area with the gaseous silicon oxide and extending the gas flow path of the gaseous silicon oxide can be achieved. Wherein the second distance D2 may be between 15mm and 25mm, the second pitch H2 may be between 20mm and 110mm, and the third pitch H3 may be between 240mm and 330 mm. In this embodiment, the second distance D2 is selected to be between 15mm and 25mm because when the second distance D2 is greater than 25mm, the gas flowing speed in the box 52 is fast, the reaction time is short, and the silicon oxide yield is easily decreased, and when the second distance D2 is less than 15mm, the silicon oxide generated between the transverse partition plate 80 and the left side plate 521 blocks the channel C, so that the yield is easily decreased; in addition, the second pitch H2 is selected to be between 20mm and 110mm and the third pitch H3 is selected to be between 240mm and 330mm, so that the ratio of the second pitch H2 to the third pitch H3 is between 1: 2.3-1: between 16.5, the user can obtain different yields and oxygen contents of the solid silicon oxide, i.e., the x value of SiOx, by adjusting the ratio of the second distance H2 to the third distance H3, and when the second distance H2 occupies a smaller area, the effect of increasing the contact area with the gaseous silicon oxide can be achieved, thereby improving the yield of the solid silicon oxide and obtaining a solid silicon oxide product with a wider x value distribution, whereas when the second distance H2 occupies a larger area, the solid silicon oxide product with a more concentrated x value distribution can be obtained.

In addition, as shown in fig. 5, the partition board may be disposed in a manner that the partition board includes two longitudinal partition boards 82 and one transverse partition board 80, the two longitudinal partition boards 82 are connected to the one transverse partition board 80, one end of each of the longitudinal partition boards 82 is connected to the surface of the transverse partition board 80, the other end of each of the longitudinal partition boards 82 extends in the direction of the air inlet 50a of the precipitation box 50 and is disposed perpendicular to the surface of the transverse partition board 80, the transverse partition board 80 is connected to the right side board 522, a third distance D3 is provided between the transverse partition board 80 and the left side board 521, a third distance H3 is provided between the top of the transverse partition board 80 and the top board 523, a fourth distance D4 is provided between the longitudinal partition board 82a of the two longitudinal partition boards 82 closer to the left side board and the left side board 521, and a fourth distance H4 is provided between the longitudinal partition board 524, and a fifth distance D5 is provided between the two longitudinal partitions 82, a sixth distance D6 is provided between the longitudinal partition 82b of the two longitudinal partitions 82, which is closer to the right side plate 522, and a fifth distance H5 is provided between the bottom plate 524, wherein the third distance D3 may be 15mm to 25mm, the third distance H3 may be 20mm to 110mm, the fourth distance H4 and the fifth distance H5 may be 100mm to 190mm, respectively, the fourth distance D4 is 60mm, the fifth distance D5 is 115mm, and the sixth distance D6 is 175mm, thereby greatly increasing the yield of solid silicon oxide deposition, wherein the number of the longitudinal partitions 82 may be one or more, and the plate surfaces of the longitudinal partitions 82 and the transverse partitions 80 may also be non-vertically arranged. In this embodiment, the third distance D3 is between 15mm and 25mm because when the third distance D3 is greater than 25mm, the gas flowing speed in the box 52 is fast, the reaction time is short, and the silicon oxide yield is easily decreased, and when the third distance D3 is less than 15mm, the silicon oxide generated between the transverse partition 80 and the left side plate 521 blocks the channel C, so the yield is easily decreased; the fourth interval H4 is selected to be between 100mm and 190mm in order to maintain a proper distance between the vertical partition 82a and the bottom plate 524 so that the gas in the cassette 50 can smoothly flow therethrough, and the fifth interval H5 is selected to be between 100mm and 190mm in order that the vertical partition 82b is disposed at a position close to the gas inlet 50a and passing through the axis X, so that solid silicon oxide is concentrated on the vertical partition 82b, and when the fifth interval H5, i.e., the minimum distance between the vertical partition 82b and the gas inlet 50a is less than 100mm, the silicon oxide generated between the vertical partition 82 and the bottom plate 524 blocks the channel C, thereby causing a decrease in yield, and when the fourth interval H4 and the fifth interval H5 are greater than 190mm, the surface area of the vertical partition 82 is indirectly decreased, thereby causing a decrease in silicon oxide yield.

Referring to table 1 below, a list of yield rates of silicon oxide obtained without a partition plate and with different partition plate arrangement manners as shown in fig. 3A to 5 is shown, where the yield rates are calculated according to a weight ratio of the yield of the solid silicon oxide S to the solid raw material to be charged, and it is known that, according to table 1, by using the partition plate arrangement manner as shown in fig. 5 with two longitudinal partition plates and one transverse partition plate, a contact area between the partition plate and the gaseous silicon oxide can be greatly increased, and thus a higher silicon oxide yield rate can be obtained.

TABLE 1

Referring to fig. 1, the apparatus 1 for preparing silicon oxide includes a thermal insulation member 100 disposed on an outer wall of the precipitation box 50, the thermal conductivity of the thermal insulation member 100 is 0.13-0.5W/m.k, preferably less than 0.24W/m.k, and the thickness is 5-80 mm, the thermal insulation member 100 may be made of carbon fiber or other thermal insulation materials, and the temperature of the precipitation box 50 can be stably maintained at 200-600 degrees by disposing the thermal insulation member 100.

In this embodiment, the thermal insulation member 100 is described as an example, in other embodiments, the number of the thermal insulation members 100 may be multiple, for example, please refer to fig. 6, the precipitation box has a first precipitation portion A1 and a second precipitation portion A2, the first precipitation portion A1 is disposed at a position close to the heater 30 of the heating device relative to the second precipitation portion A2, so as to form a temperature gradient between the first precipitation portion A1 and the second precipitation portion A2, the thermal insulation member 100 includes a first thermal insulation member 102 and a second thermal insulation member 104, the first thermal insulation member 102 is disposed at an outer wall of the first precipitation portion A1, the second thermal insulation member 104 is disposed at an outer wall of the second precipitation portion A2, and the first thermal insulation member 102 and the second thermal insulation member 104 have different thermal conductivity coefficients respectively, and the thermal conductivity coefficient is between 0.13W/m.k and 0.5W/m.k.

In this way, the temperature difference between the first deposition portion A1 and the second deposition portion A2 can be controlled by adjusting the thermal conductivity of the first thermal insulation member 102 and the second thermal insulation member 104, and the oxygen content of the solid silicon oxide deposited by the first deposition portion A1 and the second deposition portion A2 is more consistent as the temperature difference is closer, and the temperature difference may be, for example, less than 50 degrees, preferably less than 30 degrees, and most preferably less than 10 degrees, whereas the solid silicon oxide deposited by the first deposition portion A1 and the second deposition portion A2 can be deposited with different oxygen contents as the temperature difference between the first deposition portion A1 and the second deposition portion A2 is larger. In addition to the above-mentioned control of the temperature difference between the first separated portion A1 and the second separated portion A2 by adjusting the thermal conductivity of the first thermal insulator 102 and the second thermal insulator 104, the temperature difference between the first separated portion A1 and the second separated portion A2 can also be controlled by adjusting the thickness of the first thermal insulator 102 and the second thermal insulator 104, and the thickness difference between the first thermal insulator 102 and the second thermal insulator 104 is 20mm to 70mm in this embodiment. In addition to this, it is not excluded that the first heat insulating material 102 is provided only in the first deposition portion A1 or the second heat insulating material 104 is provided only in the second deposition portion A2.

As shown in fig. 7, it should be noted that, in other embodiments, the mask 90 may have other shapes, and the shape is not limited to the above embodiments, and for example, the mask may be a flat plate-shaped mask 92, which can achieve the effect of limiting the flow region of the gaseous silicon oxide.

As shown in fig. 8, in another embodiment, the apparatus for preparing silicon oxide includes an insulating member 94, the insulating member 94 may be made of carbon fiber or other insulating material, and is disposed between the precipitation box and the insulating material 12, so as to space a distance D between the precipitation box and the insulating material 12, and the distance between the precipitation box and the heating device can be controlled by adjusting the thickness of the insulating member 94, so as to control the temperature of the precipitation box, and further control the oxygen content of the solid silicon oxide, i.e. the x value of SiOx, for example, when the thickness of the insulating member 94 is increased, the distance D between the precipitation box and the insulating material 12 is increased, so as to increase the distance between the precipitation box and the heating device, and further decrease the temperature of the precipitation box, in this embodiment, the distance D is 300mm, and in other embodiments, the distance D may be less than 300mm.

In summary, the apparatus 1 for preparing silicon oxide according to the present invention can increase the contact area with the gaseous silicon oxide and extend the gas flow path of the gaseous silicon oxide by the arrangement of the partition board, thereby increasing the yield of the silicon oxide, and can control the temperature difference between the first deposition portion A1 and the second deposition portion A2 by adjusting the thermal conductivity of the first thermal insulation member 102 and the second thermal insulation member 104 or the thickness of the first thermal insulation member 102 and the second thermal insulation member 104, thereby controlling the oxygen content of the solid silicon oxide deposited in the first deposition portion A1 and the second deposition portion A2, and in addition, can control the distance between the deposition box and the heating apparatus by adjusting the thickness of the thermal insulation member 94, thereby controlling the temperature of the deposition box, and further controlling the oxygen content of the solid silicon oxide, that is, the x value of SiOx.

The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications to the present invention as described and claimed should be included in the scope of the present invention.

Description of the reference numerals

[ invention ]

1: preparation device of silicon oxide

10: heating furnace

10a: inner furnace wall

100: heat insulation piece

102: first heat insulation member

104: second heat insulation member

12: heat insulating material

20: carrying platform

30: heating device

40: crucible pot

40a: upper opening

50: precipitation box

50a: air inlet

50b: air outlet

52: box body

521: left side plate

522: right side plate

523: top board

524: base plate

525: side opening

54: box cover

60: exhaust pipe

60a: first end

60b: second end

70: air extractor

80: transverse partition

82,82a,82b: longitudinal partition

90,92: shade cover

94: thermal insulation member

90a: opening holes

A1: first precipitation part

A2: the second precipitation part

C: channel

D, D1, D2, D3, D4, D5, D6: distance between two adjacent plates

H1, H2, H3, H4, H5: distance between each other

H: height of

R: heating furnace chamber

X: axial line

S: solid silicon oxide

Claims

1. An apparatus for preparing silicon oxide, comprising:

the heating furnace is internally provided with a heating furnace chamber which is formed by enclosing a heat insulating material;

the heating device is arranged in the heating furnace cavity;

the crucible is arranged in the heating furnace chamber and used for containing a solid raw material, the solid raw material comprises silicon dioxide and silicon, and the heating device heats the crucible to enable the solid raw material to form a gaseous silicon oxide; the crucible is provided with an upper opening;

the separating box is arranged between the heating furnace chamber and the inner furnace wall of the heating furnace and is provided with an air inlet and an air outlet, the separating box comprises at least one partition plate and is arranged in the inner space of the separating box, at least one channel is formed by the at least one partition plate and the inner wall of the separating box, and the at least one channel is respectively communicated with the air inlet and the air outlet;

an exhaust conduit having a first end disposed adjacent to the upper opening of the crucible and a second end in communication with the gas inlet of the extraction cartridge; and

an air extraction device communicated with the air outlet of the precipitation box; the gas-extracting device extracts the gaseous silicon oxide from the crucible, so that the gaseous silicon oxide is contacted with the inner wall of the precipitation box and the surface of the at least one partition plate to precipitate a solid silicon oxide.

2. The apparatus of claim 1 wherein the at least one channel has a total length greater than a minimum distance between the gas inlet and the gas outlet.

3. The apparatus for producing silicon oxide according to claim 1, wherein the at least one partition comprises at least one transverse partition which is transversely disposed in the inner space of the precipitation box and intersects an axis between the gas inlet and the gas outlet.

4. The apparatus for preparing silicon oxide according to claim 3, wherein the at least one partition is plural in number, the plurality of partitions includes at least one longitudinal partition which is longitudinally disposed in the inner space of the elution box, and the at least one longitudinal partition is connected to the at least one transverse partition.

5. The apparatus for preparing silicon oxide according to claim 4, wherein one end of the at least one longitudinal partition is connected to the plate surface of the at least one transverse partition, and the other end thereof extends in the direction of the gas inlet of the elution box.

6. The apparatus of claim 5 wherein said at least one longitudinal partition passes through said axis and has a minimum distance from said gas inlet, said minimum distance being greater than or equal to 100mm and less than or equal to 190mm.

7. The apparatus for preparing silicon oxide according to claim 1, wherein the deposition cell has a first deposition portion and a second deposition portion, and the first deposition portion is disposed in a position close to the heating device with respect to the second deposition portion.

8. The apparatus for producing silicon oxide according to claim 7, wherein at least one heat insulating member is provided on an outer wall of at least one of the first deposition portion and the second deposition portion.

9. The apparatus of claim 8, wherein the at least one thermal insulator is provided in plurality, and the plurality of thermal insulators includes a first thermal insulator and a second thermal insulator, the first thermal insulator is disposed on an outer wall of the first deposition portion, the second thermal insulator is disposed on an outer wall of the second deposition portion, and the first thermal insulator and the second thermal insulator have different thermal conductivity coefficients.

10. The apparatus for preparing silicon oxide according to claim 9, wherein a thermal conductivity of the first heat insulating member and the second heat insulating member is 0.13 to 0.5W/m.k.

11. The apparatus of claim 8, wherein the at least one thermal insulator is provided in plurality, and the plurality of thermal insulators includes a first thermal insulator and a second thermal insulator, the first thermal insulator is disposed on an outer wall of the first deposition portion, the second thermal insulator is disposed on an outer wall of the second deposition portion, and the first thermal insulator and the second thermal insulator have different thicknesses.

12. The apparatus for preparing silicon oxide according to claim 1, wherein a thermal conductivity of the at least one partition is greater than or equal to 16W/m.k.

13. The apparatus of claim 1, further comprising a mask covering the crucible, the mask having an opening communicating the first end of the exhaust conduit and the interior of the crucible.

14. The apparatus for preparing silicon oxide according to claim 1, wherein a heat insulator is disposed between the elution box and the heat insulator to keep a distance between the elution box and the heat insulator.

15. The apparatus for preparing silicon oxide according to claim 1, wherein the air-extracting means is a cyclone dust collector.

16. The apparatus of claim 1, wherein the elution box comprises a box body and a cover, the box body has an opening at one side, the cover is used to close the opening, the at least one partition is plural in number, and the partitions are respectively connected to the inner wall of the box body and the cover.

17. The apparatus of claim 16, wherein the partitions attached to the inner wall of the case body and the partitions attached to the cover are staggered with each other when the cover closes the side opening.