CN103738966A

CN103738966A - Method for purifying high-purity silicon tetrachloride

Info

Publication number: CN103738966A
Application number: CN201410011907.8A
Authority: CN
Inventors: 殷万朋; 许超; 其他发明人请求不公开姓名
Original assignee: BEIJING GUO CHEN HUA XING TECHNOLOGY Co Ltd
Current assignee: BEIJING GUO CHEN HUA XING TECHNOLOGY Co Ltd
Priority date: 2014-01-12
Filing date: 2014-01-12
Publication date: 2014-04-23

Abstract

The invention relates to a purification technology of high-purity silicon tetrachloride applied to the fields of an optical fiber, photovoltaic, a semiconductor and other researches. The technology comprises the following concrete steps: 1, taking industrial silicon tetrachloride as a feeding material, carrying out pressure distillation through a first distillation tower, and feeding a low-boiling-point substance recovered from the tower top into a low-boiling-point substance storage tank; 2, carrying out pressure distillation on a tower production material obtained in the step 1 through a second distillation tower, feeding a high-boiling-point substance recovered from the tower into a high-boiling-point substance storage tank; 3, carrying out pressure distillation on a tower top production material obtained in the step 2 through a third distillation tower, returning the tower production material to the second distillation tower, and purifying in a cycle; 4, carrying out pressure distillation on the tower top production material obtained in the step 3 through a fourth distillation tower, feeding the tower top production material into the high-boiling-point substance storage tank; 5, carrying out pressure distillation on the tower production material obtained in the step 4 through a fifth distillation tower, feeding the tower production material into the high-boiling-point substance storage tank, wherein the tower top production material is the high-purity silicon tetrachloride product of which the mass concentration is greater than 99.9999%.

Description

A kind of high purity silicon tetrachloride method of purification

Technical field

The present invention relates to the purification techniques of the high purity silicon tetrachloride that a kind of optical fiber, photovoltaic, semi-conductor and other scientific research fields use, its basic demand is that silicon tetrachloride mass concentration is greater than 99.9999%, this patent utilizes large-size chemical distillation technology, adopt a plurality of rectifying tower series pressurizeds to purify, obtain the high purity silicon tetrachloride that mass concentration is greater than 99.9999%.

Background technology

The high purity silicon tetrachloride that optical fiber, photovoltaic, semi-conductor and other scientific research fields are used, it produces with transportation difficulty large, at present domestic production high purity silicon tetrachloride technique, equipment are relatively simple, unstable product quality, can not realize continuous industrial production, cannot meet the service requirements of optical fiber, photovoltaic, semi-conductor and other scientific research fields, the main dependence on import of high purity silicon tetrachloride that causes mass concentration to be greater than 99.9999%; This technological borrowing large-size chemical is produced distillation technology, adopts a plurality of rectifying tower series pressurizeds to purify, and produces the high purity silicon tetrachloride that mass concentration is greater than 99.9999%.

Summary of the invention

The high purity silicon tetrachloride that is greater than 99.9999% for efficiently producing mass concentration, this technology proposes a kind of a plurality of rectifying tower series pressurized methods of purification, for improving rectifying tower working efficiency, and the problem of considering safety in production, the method that rectifying tower selects stage number to combine at more than 55 meters packing towers at more than 90 tray columns and height, and take to add the measures such as low-pressure distillation, simultaneously, for making rectifying tower series system reach energy-conserving and environment-protective requirement, intermediates circulation is purified, and the high-boiling and low-boiling components matter of discharging is utilized.

This technology adopts a plurality of rectifying tower series pressurized methods of purification, and concrete steps are as follows:

Step 1, take industrial grade silicon tetrachloride as raw material charging, being fed to first rectifying tower is forced into 0.2-0.3Mpa and carries out rectifying, control of reflux ratio is between 60-100, the extraction of tower top low-boiling-point substance according to the 1.5-2 of low boiling mixture content in raw material doubly, low-boiling-point substance enters low-boiling-point substance storage tank, as other Chemicals raw materials, use, the flow of tower reactor production enters second rectifying tower according to material balance;

Step 2, second rectifying tower are forced into 0.1-0.15Mpa and carry out rectifying, control of reflux ratio is between 5-8, the extraction of tower reactor high boiling material is according to the 1.5-2 of high boiling material content in raw material high boiling material doubly, enter high boiling material storage tank, as other Chemicals raw materials, use, the flow of overhead extraction thing enters the 3rd rectifying tower according to material balance;

Step 3, the 3rd rectifying tower are forced into 0.1-0.15Mpa and carry out rectifying, and control of reflux ratio is between 3-6, and the intermediates of tower reactor extraction, get back to second rectifying tower, and circulation is purified, and the flow of overhead extraction thing enters the 4th rectifying tower according to material balance;

Step 4, the 4th rectifying tower are forced into 0.05-0.1Mpa and carry out rectifying, control of reflux ratio is between 250-300, the extraction of tower top low-boiling-point substance is according to the 5%-15% of material flow, low-boiling-point substance enters high boiling material storage tank, as other Chemicals raw materials, use, the flow of tower reactor production enters the 5th rectifying tower according to material balance;

Step 5, the 5th rectifying tower are forced into 0.1-0.15Mpa and carry out rectifying, control of reflux ratio is between 20-30, the extraction of tower reactor is according to the 10%-15% of material flow, thing enters high boiling material storage tank, as other Chemicals raw materials, use, overhead extraction thing is the high purity silicon tetrachloride product that mass concentration is greater than 99.9999%.

Beneficial effect: this technology adopts a plurality of rectifying tower series pressurized purifying industrial grade silicon tetrachlorides, overcome current domestic production high purity silicon tetrachloride technique, equipment is relatively simple, unstable product quality, can not realize the shortcoming of continuous industrial production, finally produce the silicon tetrachloride product of the service requirements that meets optical fiber, photovoltaic, semi-conductor and other scientific research fields, meanwhile, consider energy-conserving and environment-protective, this technology, to intermediates circulation purification, is utilized the high-boiling and low-boiling components matter of discharging.

Below in conjunction with drawings and Examples, the present invention is further described.

Accompanying drawing explanation

Fig. 1 is the system flowchart of one embodiment of the present of invention

Reference numeral: 1, first rectifying tower reboiler 2, second rectifying tower reboiler 3, the 3rd rectifying tower reboiler 4, the 4th rectifying tower reboiler 5, the 5th rectifying tower reboiler 6, first rectifying tower condenser 7, second rectifying tower condenser 8, the 3rd rectifying tower condenser 9, the 4th rectifying tower condenser 10, the 5th rectifying tower condenser 11, first rectifying tower reflux pump 12, second rectifying tower reflux pump 13, the 3rd rectifying tower reflux pump 14, the 4th rectifying tower reflux pump 15, the 5th rectifying tower reflux pump 16, the 5th rectifying tower fresh feed pump 17, first rectifying tower return tank 18, second rectifying tower return tank 19, the 3rd rectifying tower return tank 20, the 4th rectifying tower return tank 21, the 5th rectifying tower return tank 22, first rectifying tower feeding line 23, second rectifying tower feeding line 24, the 3rd rectifying tower feeding line 25, the 3rd rectifying tower heavy constituent pipeline 26, the 4th rectifying tower feeding line 27, the 5th rectifying tower feeding line 28, the 5th rectifying tower high purity silicon tetrachloride pipeline 29, the low storage tank 30 that boils, the height storage tank 31 that boils, first rectifying tower 32, second rectifying tower 33, the 3rd rectifying tower 34, the 4th rectifying tower 35, the 5th rectifying 36, exhaust pipe.

Embodiment

Step 1, silicon tetrachloride raw material enter first rectifying tower 31 by first rectifying tower feeding line 22, through more than 6 part vaporization of first rectifying tower reboiler 1 and condenser and partial condensation repeatedly, the light constituent that tower top is sloughed enters the low storage tank 29 that boils through reflux pump 11, as other Chemicals raw materials, uses;

Step 2, tower reactor production that step 1 is obtained be through second rectifying tower reboiler 2 and more than 7 part vaporization of condenser and partial condensation repeatedly, and the heavy constituent that tower reactor is sloughed enters the height storage tank 30 that boils, and as other Chemicals raw materials, uses;

Step 3, overhead extraction thing that step 2 is obtained are through the 3rd rectifying tower reboiler 3 and more than 8 part vaporization of condenser and partial condensation repeatedly, and the heavy constituent that tower reactor is sloughed is got back to second rectifying tower 32 through the 3rd rectifying tower heavy constituent pipeline 25;

Step 4, overhead extraction thing that step 3 is obtained be through the 4th rectifying tower reboiler 4 and more than 9 part vaporization of condenser and partial condensation repeatedly, and the light constituent that tower top is sloughed enters the height storage tank 30 that boils through reflux pump 14, as other Chemicals raw materials, uses;

Step 5, tower reactor production that step 4 is obtained are through the 5th rectifying tower reboiler 5 and more than 10 part vaporization of condenser and partial condensation repeatedly, overhead extraction thing is high purity silicon tetrachloride, enter the 5th rectifying tower high purity silicon tetrachloride pipeline 28, the heavy constituent that tower reactor is sloughed enters the height storage tank 30 that boils, and as other Chemicals raw materials, uses.

Claims

1. a high purity silicon tetrachloride method of purification, the high purity silicon tetrachloride that is greater than 99.9999% in order to produce mass concentration, it is characterized in that: for improving rectifying tower working efficiency, and the problem of considering safety in production, the method that rectifying tower selects tray column and packing tower to combine, and take to add the measures such as low-pressure distillation.

2. according to the requirement of right 1, it is characterized in that: for improving rectifying tower working efficiency, the method that rectifying tower selects stage number to combine at more than 55 meters packing towers at more than 90 tray columns and height.

3. according to the requirement of right 1, it is characterized in that: for making rectifying tower series system reach energy-conserving and environment-protective requirement, intermediates circulation is purified, and the high-boiling and low-boiling components matter of discharge re-uses.

4. according to the requirement of right 1, it is characterized in that: first rectifying tower is forced into 0.2-0.3Mpa and carries out rectifying, control of reflux ratio is between 60-100, and the extraction of tower top low-boiling-point substance according to the 1.5-2 of low boiling mixture content in raw material doubly.

5. according to the requirement of right 1, it is characterized in that: second rectifying tower is forced into 0.1-0.15Mpa and carries out rectifying, control of reflux ratio is between 5-8, and the extraction of tower reactor high boiling material is boiled according to the 1.5-2 of high boiling material content in raw material height doubly.

6. according to the requirement of right 1, it is characterized in that: the 3rd rectifying tower is forced into 0.1-0.15Mpa and carries out rectifying, control of reflux ratio 3-6 it.

7. according to the requirement of right 1, it is characterized in that: the 4th rectifying tower is forced into 0.05-0.1Mpa and carries out rectifying, and control of reflux ratio is between 250-300, and the extraction of tower top low-boiling-point substance is according to the 5%-15% of material flow.

8. according to the requirement of right 1, it is characterized in that: the 5th rectifying tower is forced into 0.1-0.15Mpa and carries out rectifying, and control of reflux ratio is between 20-30, and the extraction of tower reactor is according to the 10%-15 of material flow.