Purification process of high-purity titanium tetrachloride

Abstract

The invention discloses a purification process of high-purity titanium tetrachloride, which comprises the following steps: pressurizing a raw material by a pump, filtering, feeding into a rectifying tower I, separating low-boiling-point substances, and feeding a liquid phase into a rectifying tower II; high-boiling residues at the bottom of the rectifying tower II are removed from a residual liquid tank, a tower top gas phase part supplies heat to a rectifying tower I reboiler, a residual gas phase enters a first-stage adsorption column and a second-stage adsorption column after passing through a superheater, and a condensed liquid phase enters a rectifying tower III after passing through a third-stage adsorption column; discharging low-boiling-point substances at the top of the rectifying tower III, feeding a liquid phase part into a rectifying tower IV, supplying heat to a reboiler of the rectifying tower III by a gas phase of the tower IV, and feeding high-boiling-point substances at the bottom into a residual liquid tank; the other part of the liquid phase in the third rectifying tower enters a product evaporation tower, and the electronic-grade high-purity TiCl4 is obtained through a finished product filter after tower top condensation. According to the process, multi-tower rectification and three-stage adsorption are combined, cyclic utilization of heat energy is achieved through the differential pressure coupling technology, and the process has the advantages of being low in energy consumption, high in purity and stable in operation and is suitable for industrial production of electronic-grade titanium tetrachloride.

Description

Technical Field

[0001] The present invention relates to the technical field of gas purification, in particular to a purification process of high-purity titanium tetrachloride. Background Art

[0002] Electronic-grade, high-purity titanium tetrachloride (TiCl4) is a key raw material in fields such as semiconductors, photovoltaics, and high-end optical coatings. Its purity directly impacts the performance of downstream products. Traditional industrially produced titanium tetrachloride often contains impurities such as silicon tetrachloride (SiCl4), aluminum trichloride (AlCl3), ferric chloride (FeCl3), phosphorus oxychloride (POCl3), as well as boron (B), phosphorus (P), and various metal ions (such as Fe, Al, and Cr). The presence of these impurities can severely impact the electrical performance of electronic devices and the uniformity of optical coatings, necessitating their removal through efficient purification processes.

[0003] At present, the commonly used methods for purifying titanium tetrachloride in industry mainly include distillation and chemical adsorption. Distillation can effectively separate impurities with large differences in boiling points (such as SiCl4 and POCl3), but for impurities with boiling points close to titanium tetrachloride (such as certain metal chlorides) or impurities that form azeotropes with titanium tetrachloride, it is difficult to achieve electronic grade purity (usually requiring ≥5N) by relying solely on distillation. In addition, certain metal impurities (such as Fe, Cr, etc.) may remain in the form of non-volatile compounds during the distillation process and cannot be completely removed by distillation alone. Chemical adsorption can remove metal impurities in a targeted manner, but using the adsorption process alone has high energy consumption and the adsorbent is easily saturated, making it less economical.

[0004] To solve the above problems, the present invention provides a purification process for high-purity titanium tetrachloride. By optimizing the coupling mode of distillation towers and the configuration of adsorption columns, efficient purification of titanium tetrachloride is achieved. The present invention is a high-efficiency, low-energy continuous purification process, which is a multi-tower vacuum continuous distillation and multi-stage adsorption coupling process. Through a differential pressure coupling design (such as heat integration between distillation tower 1 and distillation tower 2, and distillation tower 3 and distillation tower 4), the top gas phase latent heat is recovered to provide heat to the bottom of the previous tower, significantly reducing energy consumption. At the same time, through graded adsorption in three-stage adsorption columns, metal impurities that are difficult to separate by distillation are specifically removed, and ultimately an electronic grade high-purity titanium tetrachloride product is obtained. Summary of the Invention

[0005] The present invention aims to provide a purification process for high-purity titanium tetrachloride. The process couples a multi-tower vacuum continuous distillation process with a multi-stage adsorption process. A differential pressure coupling design (such as heat integration between a first distillation tower and a second distillation tower, and between a third distillation tower and a fourth distillation tower) is used to recover the latent heat of the gas phase at the top of the tower to supply heat to the bottom of the preceding tower, thereby significantly reducing energy consumption. At the same time, graded adsorption is performed on three-stage adsorption columns to specifically remove metal impurities that are difficult to separate by distillation, thereby obtaining an electronic-grade high-purity titanium tetrachloride product.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] A purification process for high-purity titanium tetrachloride comprises the following steps:

[0008] S1, the raw material enters the raw material storage tank, the material with a purity of 3N in the raw material storage tank is pressurized by the feed pump and filtered by the raw material filter into the distillation tower 1, and gas-liquid separation is performed in the distillation tower 1, the gas phase enters the top condenser of the distillation tower 1, the gas phase of the top condenser of the distillation tower 1 goes to the exhaust gas treatment system, the liquid phase enters the top receiving tank of the distillation tower 1, and then returns to the distillation tower 1 from the top receiving tank of the distillation tower 1; part of the liquid phase of the distillation tower 1 is sent to the distillation tower 2 by the transfer pump 1, and part enters the bottom reboiler of the distillation tower 1. The gas phase of the bottom reboiler of the distillation tower 1 returns to the distillation tower 1, and the liquid phase enters the reflux tank 1, and then is sent to the distillation tower 2 by the reflux pump 1;

[0009] S2, perform gas-liquid separation in the distillation tower 2, part of the liquid phase of the distillation tower 2 returns to the distillation tower 2 through the bottom reboiler of the distillation tower 2, and part enters the residual liquid recovery tank to remove the residual liquid treatment system; part of the gas phase of the distillation tower 2 returns to the bottom reboiler of the distillation tower 1 to supply heat, and part enters the superheater at the top of the distillation tower 2. The gas phase of the superheater at the top of the distillation tower 2 goes to the exhaust gas treatment system, and the liquid phase is filtered through the intermediate filter and enters the primary adsorption column. After adsorption by the primary adsorption column, it enters the secondary adsorption column and then adsorbs again. The gas phase enters the gas phase adsorption product condenser, condenses, enters the gas phase adsorption buffer tank, and then goes to the liquid phase adsorption cooler to be cooled into a liquid phase. The liquid phase is then fed to the tertiary adsorption column by the tertiary adsorption column feed pump and sent to the tertiary liquid phase adsorption column. The gas phase after adsorption by the tertiary liquid phase adsorption column enters the distillation tower 3;

[0010] S3, perform gas-liquid separation in the distillation tower three, the gas phase enters the top condenser of the distillation tower three, the gas phase of the top condenser of the distillation tower three goes to the exhaust gas treatment system, the liquid phase enters the top receiving tank of the distillation tower three, and then returns to the distillation tower three from the top receiving tank of the distillation tower three; part of the liquid phase of the distillation tower three is sent to the distillation tower four by the transfer pump two, and part enters the bottom reboiler of the distillation tower three. The gas phase of the bottom reboiler of the distillation tower three returns to the distillation tower three, and the liquid phase enters the reflux tank two, and then passes through the reflux pump two, part of which is sent to the product evaporation tower, and part of which is sent to the distillation tower four;

[0011] S4, performing gas-liquid separation in the distillation tower 4, a portion of the liquid phase of the distillation tower 4 is returned to the distillation tower 4 through the bottom reboiler of the distillation tower 4, and a portion enters the residual liquid recovery tank to the residual liquid treatment system; the gas phase of the distillation tower 4 returns to the bottom reboiler of the distillation tower 3 to supply heat;

[0012] S5. The material in the product evaporation tower continues to undergo gas-liquid separation, and the liquid phase enters the reboiler at the bottom of the product evaporation tower. The gas phase of the reboiler at the bottom of the product evaporation tower returns to the product evaporation tower. The gas phase of the product evaporation tower enters the condenser at the top of the product evaporation tower. The gas phase of the condenser at the top of the product evaporation tower goes to the exhaust gas treatment system, and the liquid phase enters the receiving tank at the top of the product evaporation tower. Part of the liquid phase in the receiving tank at the top of the product evaporation tower returns to the product evaporation tower, and part of it enters the finished product storage tank after being filtered through the finished product filter to obtain electronic grade high-purity titanium tetrachloride product.

[0013] Preferably, the reaction temperature of the first distillation tower is controlled at 110-130° C., and the pressure is controlled at 60-65 KPa, and light components are removed in the first distillation tower.

[0014] Preferably, the reaction temperature of the second distillation tower is controlled at 135-145° C., and the pressure is controlled at 90-95 KPa, and the heavy components are removed in the second distillation tower.

[0015] Preferably, the reaction temperature of the distillation tower three is controlled to be 110-130° C., and the pressure is controlled to be 60-65 KPa, and light components are removed in the distillation tower three.

[0016] Preferably, the reaction temperature of the distillation tower four is controlled to be 135-145° C., and the pressure is controlled to be 90-95 KPa, and the heavy components are removed in the distillation tower four.

[0017] Preferably, the reaction temperature of the product evaporation tower is controlled at 140-160°C.

[0018] Preferably, the pore size of the raw material filter is 1 micron to 10 microns; the pore size of the intermediate filter is 0.1 micron to 1 micron; and the pore size of the finished product filter is 0.001 micron to 0.01 micron.

[0019] Preferably, the cold sources of the top condenser of the distillation tower 1, the top condenser of the distillation tower 3, the top condenser of the product evaporation tower, the gas phase adsorption product condenser, and the liquid phase adsorption cooler are all circulating cooling water, and the temperature of the circulating cooling water inlet water is 30°C and the pressure is 0.35MPa; the temperature of the circulating cooling water return water is 40°C and the pressure is 0.25MPa.

[0020] Preferably, the heat sources of the top superheater of the second distillation tower, the bottom reboiler of the second distillation tower, the bottom reboiler of the fourth distillation tower, and the bottom reboiler of the product evaporation tower are all thermal oil.

[0021] Due to the application of the above technical solution, the present invention has the following beneficial effects compared with the prior art:

[0022] 1. The present invention adopts multi-stage distillation (four distillation towers) and three-stage adsorption columns for coordinated purification. First, most low-boiling substances (such as SiCl4) and high-boiling substances (such as FeCl3 and AlCl3) are separated by distillation. Then, residual metal impurities (such as Fe, Al, Cr, etc.) are deeply removed through the adsorption column. The final product purity can reach 7N (99.99999%) or above, which fully meets the requirements of electronic-grade applications such as semiconductors and photovoltaics. The three-stage adsorption column performs graded adsorption. The first and second adsorption columns mainly remove easily adsorbed metal impurities. The third-stage adsorption column further purifies deeply to avoid impurity penetration, ensuring the high purity and stability of the product.

[0023] 2. The present invention adopts a differential pressure coupled heat integration design. The first and second distillation towers, as well as the third and fourth distillation towers, are differentially pressure coupled. The heat of the gaseous material at the top of the latter tower is used for reboiling at the bottom of the former tower, which greatly reduces the demand for external heat sources and reduces energy consumption by more than 30%. Continuous operation reduces energy waste, improves production efficiency, and reduces production costs.

[0024] 3. The distillation of the present invention works in synergy with adsorption. Distillation removes most of the volatile and non-volatile impurities, and the adsorption column specifically removes metal ions (such as Fe 3+ 、Al 3+ etc.), avoiding the limitations of a single process; the residual liquids at the top and bottom of each distillation tower enter the recovery tank and can be further processed or reused, reducing waste liquid discharge, avoiding secondary pollution, and improving raw material utilization;

[0025] 4. The present invention operates continuously throughout the entire process, from raw material feeding to product extraction, with full automated control, which reduces human operation errors, improves product consistency, and has a continuous and stable process, making it suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific embodiments or the description of the prior art. Obviously, some of the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be made based on these drawings without paying any creative work.

[0027] Figure 1 This is a process flow chart of Example 1 of the present invention;

[0028] Among them, 1-distillation tower one; 2-distillation tower two; 3-distillation tower three; 4-distillation tower four; 5-product evaporation tower; 6-primary adsorption column; 7-secondary adsorption column; 8-tertiary liquid phase adsorption column; 9-top condenser of distillation tower one; 10-top superheater of distillation tower two; 11-top condenser of distillation tower three; 12-top condenser of product evaporation tower; 13-gas phase adsorption product condenser; 14-liquid phase adsorption cooler; 15-top receiving tank of distillation tower one; 16-top receiving tank of distillation tower three; 17-top receiving tank of product evaporation tower; 18-raw material storage tank; 19-Gas phase adsorption buffer tank; 20-Reflux tank 1; 21-Reflux tank 2; 22-Finished product storage tank; 23-Residual liquid recovery tank; 24-Raw material filter; 25-Intermediate filter; 26-Finished product filter; 27-Bottom reboiler of distillation tower 1; 28-Bottom reboiler of distillation tower 2; 29-Bottom reboiler of distillation tower 3; 30-Bottom reboiler of distillation tower 4; 31-Bottom reboiler of product evaporation tower; 32-Feed pump; 33-Third-stage adsorption column feed pump; 34-Transfer pump 1; 35-Transfer pump 2; 36-Reflux pump 1; 37-Reflux pump 2. DETAILED DESCRIPTION

[0029] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, a specific implementation scheme is now described in detail.

[0030] The present invention is further described below with reference to the following examples, but the present invention is not limited to the following examples. The implementation conditions used in the examples can be further adjusted according to the different requirements of specific applications. The implementation conditions not specified are conventional conditions in the industry. The technical features involved in the various embodiments of the present invention may be combined with each other as long as they do not conflict with each other.

[0031] Example 1

[0032] See attached Figure 1 This embodiment provides a purification process for high-purity titanium tetrachloride, comprising the following steps:

[0033] S1, raw materials enter the raw material storage tank (18), the materials with a purity of 3N in the raw material storage tank are pressurized by the feed pump (32) and filtered by the raw material filter (24) and enter the distillation tower one (1), gas-liquid separation is carried out in the distillation tower one, the gas phase enters the top condenser (9) of the distillation tower one, the gas phase of the top condenser of the distillation tower one goes to the waste gas treatment system, the liquid phase enters the top receiving tank (15) of the distillation tower one, and then returns to the distillation tower one from the top receiving tank of the distillation tower one; a part of the liquid phase of the distillation tower one is sent to the distillation tower two (2) through the delivery pump one (34), and a part enters the bottom reboiler (27) of the distillation tower one, the gas phase of the bottom reboiler of the distillation tower one returns to the distillation tower one, the liquid phase enters the reflux tank one (20), and then is sent to the distillation tower two through the reflux pump one (36);

[0034] S2, gas-liquid separation is carried out in the distillation tower 2, a part of the liquid phase of the distillation tower 2 is returned to the distillation tower 2 through the bottom reboiler (28) of the distillation tower 2, and a part enters the residual liquid recovery storage tank (23) to remove the residual liquid treatment system; a part of the gas phase of the distillation tower 2 is returned to the bottom reboiler of the distillation tower 1 to supply heat, and a part enters the top superheater (10) of the distillation tower 2, and the gas phase of the top superheater of the distillation tower 2 is removed to the waste gas treatment system, the liquid phase is filtered by the intermediate filter (25) and enters the first-stage adsorption column (6), and after adsorption by the first-stage adsorption column, enters the second-stage adsorption column (7), and after adsorption again, the gas phase enters the gas phase adsorption product condenser (13), enters the gas phase adsorption buffer tank (19) after condensation, and then goes to the liquid phase adsorption cooler (14) to cool to the liquid phase, and the liquid phase is then sent to the third-stage liquid phase adsorption column (8) through the third-stage adsorption column feed pump (33), and the gas phase after adsorption by the third-stage liquid phase adsorption column enters the distillation tower 3;

[0035] S3, gas-liquid separation is carried out in the distillation tower three (3), the gas phase enters the top condenser (11) of the distillation tower three, the gas phase of the top condenser of the distillation tower three goes to the waste gas treatment system, the liquid phase enters the top receiving tank (16) of the distillation tower three, and then returns to the distillation tower three from the top receiving tank of the distillation tower three; a part of the liquid phase of the distillation tower three is sent to the distillation tower four (4) through the delivery pump two (35), and a part enters the bottom reboiler (29) of the distillation tower three, the gas phase of the bottom reboiler of the distillation tower three returns to the distillation tower three, the liquid phase enters the reflux tank two (21), and then a part is sent to the product evaporation tower through the reflux pump two (37), and a part is sent to the distillation tower four;

[0036] S4, performing gas-liquid separation in the distillation tower 4 (4), a portion of the liquid phase of the distillation tower 4 is returned to the distillation tower 4 through the bottom reboiler (30) of the distillation tower 4, and a portion enters the residual liquid recovery tank to remove the residual liquid treatment system; the gas phase of the distillation tower 4 returns to the bottom reboiler of the distillation tower 3 to supply heat;

[0037] S5, the material of the product evaporation tower (5) continues to be separated into gas and liquid, the liquid phase enters the reboiler (31) at the bottom of the product evaporation tower, the gas phase of the reboiler at the bottom of the product evaporation tower returns to the product evaporation tower, the gas phase of the product evaporation tower enters the condenser (12) at the top of the product evaporation tower, the gas phase of the condenser at the top of the product evaporation tower goes to the waste gas treatment system, the liquid phase enters the receiving tank (17) at the top of the product evaporation tower, a part of the liquid phase of the receiving tank at the top of the product evaporation tower returns to the product evaporation tower, and a part of the liquid phase enters the finished product storage tank (22) after being filtered through the finished product filter (26) to obtain an electronic grade high-purity titanium tetrachloride product;

[0038] Furthermore, the reaction temperature of the distillation tower 1 is controlled at 120° C., and the pressure is controlled at 65 KPa, and light components are removed in the distillation tower 1;

[0039] Furthermore, the reaction temperature of the second distillation tower is controlled at 135° C., and the pressure is controlled at 95 KPa, and heavy components are removed in the second distillation tower;

[0040] Furthermore, the reaction temperature of the distillation tower 3 is controlled at 120° C., and the pressure is controlled at 65 KPa, and light components are removed in the distillation tower 3;

[0041] Furthermore, the reaction temperature of the distillation tower 4 is controlled at 135° C., and the pressure is controlled at 95 KPa, and heavy components are removed in the distillation tower 4;

[0042] Furthermore, the reaction temperature of the product evaporation tower is controlled at 150°C;

[0043] Furthermore, the pore size of the raw material filter is 1 micron to 10 microns; the pore size of the intermediate filter is 0.1 micron to 1 micron; the pore size of the finished product filter is 0.001 micron to 0.01 micron;

[0044] Furthermore, the cooling sources of the top condenser of the distillation tower 1, the top condenser of the distillation tower 3, the top condenser of the product evaporation tower, the gas phase adsorption product condenser, and the liquid phase adsorption cooler are all circulating cooling water, and the temperature of the circulating cooling water inlet water is 30°C and the pressure is 0.35MPa; the temperature of the circulating cooling water return water is 40°C and the pressure is 0.25MPa;

[0045] Furthermore, the heat sources of the top superheater of the second distillation tower, the bottom reboiler of the second distillation tower, the bottom reboiler of the fourth distillation tower, and the bottom reboiler of the product evaporation tower are all thermal oil.

[0046] In summary, the present invention adopts multi-stage distillation (four distillation towers) and three-stage adsorption column for coordinated purification. First, most of the low-boiling substances (such as SiCl4) and high-boiling substances (such as FeCl3, AlCl3) are separated by distillation, and then the residual metal impurities (such as Fe, Al, Cr, etc.) are deeply removed through the adsorption column. The purity of the final product can reach 7N (99.99999%) or more, which fully meets the requirements of electronic-grade applications such as semiconductors and photovoltaics. The three-stage adsorption column performs graded adsorption. The first and second adsorption columns mainly remove easily adsorbed metal impurities, and the third adsorption column further deeply removes the residual metal impurities. Purification, avoid impurity penetration, ensure the high purity and stability of the product; the present invention adopts differential pressure coupling heat integration design, distillation tower 1 and distillation tower 2, distillation tower 3 and distillation tower 4 adopt differential pressure coupling, the heat of the gas phase material at the top of the rear tower is used for reboiling at the bottom of the front tower, greatly reducing the demand for external heat source, and reducing energy consumption by more than 30%; continuous operation reduces energy waste, improves production efficiency, and reduces production costs; the present invention has synergistic effect of distillation and adsorption, distillation removes most of the volatile and non-volatile impurities, and the adsorption column specifically removes metal ions (such as Fe 3+ 、Al 3+etc.), avoiding the limitations of a single process; the residual liquids at the top and bottom of each distillation tower enter the recovery tank and can be further processed or reused, reducing waste liquid discharge, avoiding secondary pollution, and improving raw material utilization; the present invention operates continuously throughout the entire process, from raw material feeding to product extraction, with full automated control, reducing human operation errors, improving product consistency, and making the process continuous and stable, suitable for industrial production.

[0047] The above-described embodiment merely represents one embodiment of the present invention. While the description is relatively specific and detailed, it should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make various modifications and improvements without departing from the spirit of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A purification process for high-purity titanium tetrachloride, characterized in that: The steps include: S1, the raw material enters the raw material storage tank, the material with a purity of 3N in the raw material storage tank is pressurized by the feed pump and filtered by the raw material filter into the distillation tower 1, and gas-liquid separation is performed in the distillation tower 1, the gas phase enters the top condenser of the distillation tower 1, the gas phase of the top condenser of the distillation tower 1 goes to the exhaust gas treatment system, the liquid phase enters the top receiving tank of the distillation tower 1, and then returns to the distillation tower 1 from the top receiving tank of the distillation tower 1; part of the liquid phase of the distillation tower 1 is sent to the distillation tower 2 by the transfer pump 1, and part enters the bottom reboiler of the distillation tower 1. The gas phase of the bottom reboiler of the distillation tower 1 returns to the distillation tower 1, and the liquid phase enters the reflux tank 1, and then is sent to the distillation tower 2 by the reflux pump 1; S2, perform gas-liquid separation in the distillation tower 2, part of the liquid phase of the distillation tower 2 returns to the distillation tower 2 through the bottom reboiler of the distillation tower 2, and part enters the residual liquid recovery tank to remove the residual liquid treatment system; part of the gas phase of the distillation tower 2 returns to the bottom reboiler of the distillation tower 1 to supply heat, and part enters the superheater at the top of the distillation tower 2. The gas phase of the superheater at the top of the distillation tower 2 goes to the exhaust gas treatment system, and the liquid phase is filtered through the intermediate filter and enters the primary adsorption column. After adsorption by the primary adsorption column, it enters the secondary adsorption column and then adsorbs again. The gas phase enters the gas phase adsorption product condenser, condenses, enters the gas phase adsorption buffer tank, and then goes to the liquid phase adsorption cooler to be cooled into a liquid phase. The liquid phase is then fed to the tertiary adsorption column by the tertiary adsorption column feed pump and sent to the tertiary liquid phase adsorption column. The gas phase after adsorption by the tertiary liquid phase adsorption column enters the distillation tower 3; S3, perform gas-liquid separation in the distillation tower three, the gas phase enters the top condenser of the distillation tower three, the gas phase of the top condenser of the distillation tower three goes to the exhaust gas treatment system, the liquid phase enters the top receiving tank of the distillation tower three, and then returns to the distillation tower three from the top receiving tank of the distillation tower three; part of the liquid phase of the distillation tower three is sent to the distillation tower four by the transfer pump two, and part enters the bottom reboiler of the distillation tower three. The gas phase of the bottom reboiler of the distillation tower three returns to the distillation tower three, and the liquid phase enters the reflux tank two, and then passes through the reflux pump two, part of which is sent to the product evaporation tower, and part of which is sent to the distillation tower four; S4, performing gas-liquid separation in the distillation tower 4, a portion of the liquid phase of the distillation tower 4 is returned to the distillation tower 4 through the bottom reboiler of the distillation tower 4, and a portion enters the residual liquid recovery tank to the residual liquid treatment system; the gas phase of the distillation tower 4 returns to the bottom reboiler of the distillation tower 3 to supply heat; S5. The material in the product evaporation tower continues to undergo gas-liquid separation, and the liquid phase enters the reboiler at the bottom of the product evaporation tower. The gas phase of the reboiler at the bottom of the product evaporation tower returns to the product evaporation tower. The gas phase of the product evaporation tower enters the condenser at the top of the product evaporation tower. The gas phase of the condenser at the top of the product evaporation tower goes to the exhaust gas treatment system, and the liquid phase enters the receiving tank at the top of the product evaporation tower. Part of the liquid phase in the receiving tank at the top of the product evaporation tower returns to the product evaporation tower, and part of it enters the finished product storage tank after being filtered through the finished product filter to obtain electronic grade high-purity titanium tetrachloride product.

2. A purification process for high-purity titanium tetrachloride as claimed in claim 1, characterized in that: The reaction temperature of the first distillation tower is controlled at 110-130° C., and the pressure is controlled at 60-65 KPa, and light components are removed in the first distillation tower.

3. A purification process for high-purity titanium tetrachloride according to claim 1, characterized in that: The reaction temperature of the second distillation tower is controlled at 135-145° C., and the pressure is controlled at 90-95 KPa, and heavy components are removed in the second distillation tower.

4. A purification process for high-purity titanium tetrachloride according to claim 1, characterized in that: The reaction temperature of the distillation tower three is controlled to be 110-130° C., and the pressure is controlled to be 60-65 KPa, and light components are removed in the distillation tower three.

5. A purification process for high-purity titanium tetrachloride according to claim 1, characterized in that: The reaction temperature of the distillation tower 4 is controlled at 135-145° C., and the pressure is controlled at 90-95 KPa, and the heavy components are removed in the distillation tower 4.

6. A purification process for high-purity titanium tetrachloride according to claim 1, characterized in that: The reaction temperature of the product evaporation tower is controlled at 140-160°C.

7. A process for purifying high-purity titanium tetrachloride according to claim 1, characterized in that: The pore size of the raw material filter is 1 micron to 10 microns; the pore size of the intermediate filter is 0.1 micron to 1 micron; and the pore size of the finished product filter is 0.001 micron to 0.01 micron.

8. A process for purifying high-purity titanium tetrachloride according to claim 1, characterized in that: The cold sources of the top condenser of the distillation tower one, the top condenser of the distillation tower three, the top condenser of the product evaporation tower, the gas phase adsorption product condenser, and the liquid phase adsorption cooler are all circulating cooling water. The temperature of the circulating cooling water inlet water is 30°C and the pressure is 0.35MPa; the temperature of the circulating cooling water return water is 40°C and the pressure is 0.25MPa.

9. A process for purifying high-purity titanium tetrachloride according to claim 1, characterized in that: The heat sources of the top superheater of the second distillation tower, the bottom reboiler of the second distillation tower, the bottom reboiler of the fourth distillation tower, and the bottom reboiler of the product evaporation tower are all thermal oil.

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