Method for preparing high-activity titanium dioxide from special titanium tetrachloride

Abstract

The invention relates to a method for preparing high-activity titanium dioxide from special titanium tetrachloride, which comprises the following steps of: introducing qualified titanium tetrachloride into a preheating furnace and heating to obtain gas-phase titanium tetrachloride; the method comprises the following steps: introducing gas-phase titanium tetrachloride into a first reactor, introducing chlorine into the first reactor, and adding aluminum to obtain special gas-phase titanium tetrachloride; specially-made gas-phase titanium tetrachloride is introduced into a second reactor and heated, then oxygen and a potassium chloride solution are introduced, and a high-activity titanium dioxide product is obtained. According to the method for preparing the high-activity titanium dioxide, the surface of the titanium dioxide is modified, ion doping and morphology adjustment are carried out, and the method has important significance for promoting environmental protection and is wide in application and popularization prospect and remarkable in economic benefit and social benefit.

Description

Technical Field

[0001] The invention belongs to the technical field of titanium dioxide production, and more specifically, relates to a method for preparing high-activity titanium dioxide by using specially prepared titanium tetrachloride. Background Art

[0002] Titanium dioxide, with its excellent stability and ability to directly utilize solar energy, has shown great potential in the field of photocatalysts. It can effectively degrade and remove various pollutants, providing strong support for environmental protection. However, like many excellent materials, titanium dioxide is not perfect. Its bandgap is too large, resulting in only the absorption of ultraviolet light, while the utilization rate of visible light is relatively low. This defect has largely limited the widespread application of titanium dioxide, forcing scientists to find ways to improve it.

[0003] In order to overcome this challenge, researchers have conducted a lot of exploration and practice. They found that the photocatalytic activity of titanium dioxide can be effectively improved through surface modification, ion doping and morphology regulation. These methods can adjust the energy band structure of titanium dioxide and broaden its light absorption range, thereby improving the utilization of visible light.

[0004] Among the many improved methods, the hydrogenation method proposed by Chen Xiaobo and others from the University of California, Los Angeles in 2011 is particularly eye-catching. They placed white titanium dioxide in a tube furnace, introduced hydrogen, and left it to stand for several days under specific temperature and pressure conditions, successfully constructing a disordered structure on the surface of the titanium dioxide lattice. The existence of this disordered structure significantly narrowed the band gap width of the highly active titanium dioxide nanomaterial to 0.15eV (the original band gap was 3~3.2eV), thereby greatly improving the visible light response performance and quantum efficiency of the material.

[0005] In addition to the hydrogenation method, there are many other methods for preparing highly active titanium dioxide. Among them, the atmosphere roasting method, metal thermal reduction method and femtosecond pulse method all prepare nano titanium dioxide first and then perform surface modification. These methods improve the photocatalytic activity by changing the surface structure and chemical properties of titanium dioxide. The chemical reduction method and sol-gel method prepare nano titanium dioxide in solution and modify its surface at the same time. These methods have the advantages of simple operation and low cost, so they have broad prospects in industrial applications.

[0006] However, although these methods have achieved certain results, there are still some problems and challenges. Currently, scientists are in urgent need of a more efficient and convenient method that can modify the surface of titanium dioxide while preparing it, and perform ion doping and morphology adjustment. The oxidation-reduction gas phase method is a new method with potential, which is expected to provide new ideas and approaches for the modification of titanium dioxide in future research. Summary of the invention

[0007] The object of the present invention is to provide a method for preparing high-activity titanium dioxide using special titanium tetrachloride. The method adopts gas phase reaction to prepare high-activity titanium dioxide, can modify the surface of titanium dioxide, and perform ion doping and morphology adjustment.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions, which are specifically described as follows: According to one aspect of the present invention, a method for preparing highly active titanium dioxide by using specially prepared titanium tetrachloride is provided, comprising the following steps: 1) introducing qualified titanium tetrachloride into a preheating furnace and heating it to obtain gaseous titanium tetrachloride; 2) introducing gaseous titanium tetrachloride into the first reactor, while introducing chlorine gas and adding aluminum into the first reactor to obtain special gaseous titanium tetrachloride; 3) The specially prepared gaseous titanium tetrachloride is introduced into the second reactor and heated, and then oxygen and potassium chloride solution are introduced to obtain a highly active titanium dioxide product.

[0009] In one embodiment of the present invention, in step 1), qualified titanium tetrachloride is heated to above 400° C. and converted into a gas phase to obtain gas phase titanium tetrachloride.

[0010] In one embodiment of the present invention, in step 2), gaseous titanium tetrachloride, chlorine and aluminum are continuously introduced into the first reaction container.

[0011] In one embodiment of the present invention, in step 2), the mass ratio of chlorine to aluminum is not greater than 3.92.

[0012] In one embodiment of the present invention, in step 2), the mass ratio of gaseous titanium tetrachloride to chlorine is 120-155.

[0013] In one embodiment of the present invention, in step 3), hydrogen, carbon monoxide or toluene is burned in the second reactor to generate heat for heating.

[0014] In one embodiment of the present invention, in step 3), heating is performed by a high temperature electric furnace or plasma.

[0015] In one embodiment of the present invention, in step 3), the heating temperature is 1600-1800°C.

[0016] In one embodiment of the present invention, in step 3), the mass ratio of the specially prepared titanium tetrachloride to oxygen is 5.93-20.0.

[0017] In one embodiment of the present invention, in step 3), the mass percentage of titanium dioxide converted from potassium chloride to specially prepared titanium tetrachloride is 0.002-0.005%.

[0018] By adopting the above technical solution, the present invention has the following advantages compared with the prior art: The present invention provides a method for preparing highly active titanium dioxide, and simultaneously modifies the titanium dioxide surface, performs ion doping and morphology adjustment, which is of great significance for promoting environmental protection, has broad prospects for promotion and application, and has significant economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or additional aspects and advantages of the present invention will be more obvious and easily understood in the description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 The present invention provides a schematic flow diagram of a method for preparing high-activity titanium dioxide using specially prepared titanium tetrachloride. DETAILED DESCRIPTION

[0020] It should be understood that the embodiments of the present invention shown in the exemplary embodiments are only illustrative. Although only a few embodiments are described in detail in the present invention, it is easy for those skilled in the art to appreciate that multiple modifications are feasible without actually departing from the teaching of the subject matter of the present invention. Accordingly, all such modifications should be included within the scope of the present invention. Without departing from the gist of the present invention, other replacements, modifications, changes and deletions may be made to the design, operating conditions and parameters of the following exemplary embodiments.

[0021] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0022] like Figure 1 As shown, the present invention provides a method for preparing high-activity titanium dioxide from specially prepared titanium tetrachloride, comprising the following steps: S101: introducing qualified titanium tetrachloride into a preheating furnace and heating it to obtain gaseous titanium tetrachloride; S102: introducing gaseous titanium tetrachloride into the first reactor, while introducing chlorine gas and adding aluminum into the first reactor to obtain special gaseous titanium tetrachloride; S103: introducing the specially prepared gaseous titanium tetrachloride into the second reactor and heating it, and then introducing oxygen and potassium chloride solution to obtain a highly active titanium dioxide product.

[0023] The present invention provides a method for preparing highly active titanium dioxide, and simultaneously modifies the titanium dioxide surface, performs ion doping and morphology adjustment, which is of great significance for promoting environmental protection, has broad prospects for promotion and application, and has significant economic and social benefits.

[0024] In the above-mentioned method for preparing highly active titanium dioxide by using specially prepared titanium tetrachloride, in step S101, qualified titanium tetrachloride is heated to above 400° C. and converted into a gas phase to obtain gas phase titanium tetrachloride.

[0025] In the above-mentioned method for preparing high-activity titanium dioxide by using specially prepared titanium tetrachloride, in step S102, gaseous titanium tetrachloride, chlorine and aluminum are continuously introduced into the first reaction container.

[0026] In the above-mentioned method for preparing high-activity titanium dioxide from a specially prepared titanium tetrachloride, in step S102, the mass ratio of chlorine to aluminum is not greater than 3.92.

[0027] In the above-mentioned method for preparing high-activity titanium dioxide from a specially prepared titanium tetrachloride, in step S103, the mass ratio of gaseous titanium tetrachloride to chlorine is 120-155.

[0028] In the above-mentioned method for preparing high-activity titanium dioxide by using specially prepared titanium tetrachloride, in step S103, hydrogen, carbon monoxide or toluene is burned in the second reactor to generate heat for heating.

[0029] In the above-mentioned method for preparing high-activity titanium dioxide by using specially prepared titanium tetrachloride, in step S103, heating is performed by a high-temperature electric furnace or plasma.

[0030] In the above-mentioned method for preparing high-activity titanium dioxide from a specially prepared titanium tetrachloride, in step S103, the heating temperature is 1600-1800°C.

[0031] In the above-mentioned method for preparing high-activity titanium dioxide from a specially prepared titanium tetrachloride, in step S103, the mass ratio of the specially prepared titanium tetrachloride to oxygen is 5.93-20.0.

[0032] In the above-mentioned method for preparing high-activity titanium dioxide from a special titanium tetrachloride, in step S103, the mass percentage of titanium dioxide converted from potassium chloride and special titanium tetrachloride is 0.002-0.005%.

[0033] The above technical solution of the present invention is described in detail below through specific embodiments.

[0034] The present invention discloses a method for preparing high-activity titanium dioxide using specially prepared titanium tetrachloride. The method adopts a gas phase reaction to prepare high-activity titanium dioxide, and comprises the following steps: Introducing qualified titanium tetrachloride into a preheating furnace, raising its temperature to above 400°C, converting it into a gas phase, and obtaining gas phase titanium tetrachloride; The obtained gaseous titanium tetrachloride is introduced into a first reactor, and chlorine is introduced into the first reactor at the same time, and aluminum is added, and the gaseous titanium tetrachloride, chlorine and aluminum are continuously introduced into the first reactor, and the mass ratio of chlorine introduced into the first reactor to aluminum is ≤3.92; the mass ratio of gaseous titanium tetrachloride introduced into the first reactor to chlorine is between 120-155, and special gaseous titanium tetrachloride is obtained in the first reactor; The special titanium tetrachloride obtained from the first reactor is introduced into the second reactor, and hydrogen, carbon monoxide or toluene and other combustible gases are burned in the second reactor to release heat to ensure the temperature of the second reactor, or heated by a high-temperature electric furnace, or heated by plasma, so that the temperature of the reaction zone is between 1600℃-1800℃, and then oxygen and potassium chloride solution are introduced, the mass ratio of special titanium tetrachloride to oxygen is between 5.93-20.0, and the mass percentage of titanium dioxide converted from potassium chloride to special titanium tetrachloride is between 0.002-0.005%. Potassium chloride plays a role in adjusting the morphology of titanium dioxide. The special titanium tetrachloride realizes the surface modification of titanium dioxide, and finally obtains a high-activity titanium dioxide product.

[0035] There is no mass loss of titanium tetrachloride in the whole reaction process, that is, the mass of qualified titanium tetrachloride is the same as that of gas phase titanium tetrachloride and special titanium tetrachloride.

[0036] Example 1 A method for preparing highly active titanium dioxide from specially prepared titanium tetrachloride, the specific operating steps are as follows: Qualified titanium tetrachloride was pumped into the preheating furnace at a flow rate of 5 kg / h, and titanium tetrachloride was heated to 450°C in the preheating furnace to obtain gaseous titanium tetrachloride, which was introduced into the first reactor. Chlorine gas was introduced into the first reactor at 0.037 kg / h and aluminum was added at 0.013 kg / h. Special titanium tetrachloride was obtained in the first reactor, and the special titanium tetrachloride was introduced into the second reactor. The second reactor was heated to 1600°C by an external high-temperature electric furnace, and oxygen gas was introduced at 0.8 kg / h and potassium chloride at 4.211×10 -5 kg / h, thereby obtaining a highly active titanium dioxide product.

[0037] Example 2 A method for preparing highly active titanium dioxide from specially prepared titanium tetrachloride, the specific operating steps are as follows: Qualified titanium tetrachloride was pumped into the preheating furnace at a flow rate of 5 kg / h, and titanium tetrachloride was heated to 430°C in the preheating furnace to obtain gaseous titanium tetrachloride. The gaseous titanium tetrachloride was introduced into the first reactor, and chlorine gas of 0.04 kg / h and aluminum of 0.015 kg / h were introduced into the first reactor at the same time. Special titanium tetrachloride was obtained in the first reactor, and the special titanium tetrachloride was introduced into the second reactor. The second reactor was heated to 1650°C by an external high-temperature electric furnace, and oxygen of 0.8 kg / h and potassium chloride of 4.211×10 -5 kg / h, thereby obtaining a highly active titanium dioxide product.

[0038] Example 3 A method for preparing highly active titanium dioxide from specially prepared titanium tetrachloride, the specific operating steps are as follows: Qualified titanium tetrachloride was pumped into the preheating furnace at a flow rate of 5 kg / h, and titanium tetrachloride was heated to 400°C in the preheating furnace to obtain gaseous titanium tetrachloride. The gaseous titanium tetrachloride was introduced into the first reactor, and chlorine gas of 0.0323 kg / h and aluminum of 0.015 kg / h were introduced into the first reactor at the same time. Special titanium tetrachloride was obtained in the first reactor, and the special titanium tetrachloride was introduced into the second reactor. The second reactor was heated to 1750°C by external plasma, and oxygen gas of 0.75 kg / h and potassium chloride of 9.36×10 -5 kg / h, thereby obtaining a highly active titanium dioxide product.

[0039] Example 4 A method for preparing highly active titanium dioxide from specially prepared titanium tetrachloride, the specific operating steps are as follows: Qualified titanium tetrachloride is pumped into the preheating furnace at a flow rate of 5kg / h, and the titanium tetrachloride is heated to 420°C in the preheating furnace to obtain gaseous titanium tetrachloride, and the gaseous titanium tetrachloride enters the first reactor, and 0.035kg / h of chlorine and 0.013kg / h of aluminum are simultaneously introduced into the first reactor, and the first reactor obtains special titanium tetrachloride, which is introduced into the second reactor, and the second reactor is heated to 1800°C by external plasma, and 0.7kg / h of oxygen and 5.241×10-5kg / h of potassium chloride are introduced, so as to obtain a high-activity titanium dioxide product.

[0040] Example 5 Qualified titanium tetrachloride was pumped into the preheating furnace at a flow rate of 6 kg / h, and titanium tetrachloride was heated to 430°C in the preheating furnace to obtain gaseous titanium tetrachloride, which was introduced into the first reactor. Chlorine gas was introduced into the first reactor at 0.050 kg / h and aluminum was added at 0.013 kg / h. Special titanium tetrachloride was obtained in the first reactor, and the special titanium tetrachloride was introduced into the second reactor. The second reactor was heated to 1600°C by an external high-temperature electric furnace, and oxygen gas was introduced at 1.01 kg / h and potassium chloride at 4.211×10 -5 kg / h, thereby obtaining a highly active titanium dioxide product.

[0041] Example 6 A method for preparing highly active titanium dioxide from specially prepared titanium tetrachloride, the specific operating steps are as follows: Qualified titanium tetrachloride was pumped into the preheating furnace at a flow rate of 6 kg / h. Titanium tetrachloride was heated to 480°C in the preheating furnace to obtain gaseous titanium tetrachloride. The gaseous titanium tetrachloride was introduced into the first reactor. Chlorine gas was introduced into the first reactor at 0.0387 kg / h and aluminum was added at 0.0129 kg / h. Special titanium tetrachloride was obtained in the first reactor. The special titanium tetrachloride was introduced into the second reactor. Hydrogen was burned in the second reactor to release heat to ensure that the heating temperature was raised to 1650°C. Oxygen gas was introduced at 0.3 kg / h and potassium chloride was introduced at 10.5×10 -5 kg / h, thereby obtaining a highly active titanium dioxide product.

[0042] Example 7 A method for preparing highly active titanium dioxide from specially prepared titanium tetrachloride, the specific operating steps are as follows: Qualified titanium tetrachloride was pumped into the preheating furnace at a flow rate of 6 kg / h. Titanium tetrachloride was heated to 450°C in the preheating furnace to obtain gaseous titanium tetrachloride. The gaseous titanium tetrachloride was introduced into the first reactor. Chlorine gas was introduced into the first reactor at 0.046 kg / h and aluminum was added at 0.023 kg / h. Special titanium tetrachloride was obtained in the first reactor. The special titanium tetrachloride was introduced into the second reactor. Carbon monoxide was burned in the second reactor to release heat to ensure that the heating temperature was raised to 1750°C. Oxygen gas was introduced at 0.6 kg / h and potassium chloride was introduced at 6.32×10 -5 kg / h, thereby obtaining a highly active titanium dioxide product.

[0043] Example 8 A method for preparing highly active titanium dioxide from specially prepared titanium tetrachloride, the specific operating steps are as follows: Qualified titanium tetrachloride was pumped into the preheating furnace at a flow rate of 6 kg / h. Titanium tetrachloride was heated to 420°C in the preheating furnace to obtain gaseous titanium tetrachloride. The gaseous titanium tetrachloride was introduced into the first reactor. Chlorine gas was introduced into the first reactor at 0.04 kg / h and aluminum was added at 0.02 kg / h. Special titanium tetrachloride was obtained in the first reactor. The special titanium tetrachloride was introduced into the second reactor. Toluene was burned in the second reactor to release heat to ensure that the heating temperature was raised to 1800°C. Oxygen gas was introduced at 0.4 kg / h and potassium chloride was introduced at 8.241×10 -5 kg / h, thereby obtaining a highly active titanium dioxide product.

[0044] It can be seen from the above examples 1-8 that the present invention uses an oxidation-reduction gas phase method to prepare a high-activity titanium dioxide product. The present invention modifies the surface of titanium dioxide while preparing titanium dioxide, and performs ion doping and morphology adjustment.

[0045] It should be particularly pointed out that the various components or steps in the above-mentioned embodiments can be cross-linked, replaced, added, or deleted with each other. Therefore, the combinations formed by these reasonable arrangements and combinations should also fall within the scope of protection of the present invention, and the scope of protection of the present invention should not be limited to the embodiments.

[0046] The above are exemplary embodiments disclosed in the present invention. The order disclosed in the above embodiments of the present invention is for description only and does not represent the advantages and disadvantages of the embodiments. However, it should be noted that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope disclosed in the embodiments of the present invention (including the claims) is limited to these examples. Various changes and modifications may be made without departing from the scope defined in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.

[0047] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the embodiments of the present invention as described above, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A method for preparing highly active titanium dioxide from specially prepared titanium tetrachloride, characterized in that: The following steps are involved: 1) introducing qualified titanium tetrachloride into a preheating furnace and heating it to obtain gaseous titanium tetrachloride; 2) introducing gaseous titanium tetrachloride into the first reactor, while introducing chlorine gas and adding aluminum into the first reactor to obtain special gaseous titanium tetrachloride; 3) The specially prepared gaseous titanium tetrachloride is introduced into the second reactor and heated, and then oxygen and potassium chloride solution are introduced to obtain a highly active titanium dioxide product.

2. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 1), qualified titanium tetrachloride is heated to above 400° C. and converted into a gas phase to obtain gas phase titanium tetrachloride.

3. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 2), gaseous titanium tetrachloride, chlorine gas and aluminum are continuously introduced into a first reaction vessel.

4. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 2), the mass ratio of chlorine to aluminum is not greater than 3.

92.

5. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 2), the mass ratio of gaseous titanium tetrachloride to chlorine is 120-155.

6. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 3), hydrogen, carbon monoxide or toluene is burned in the second reactor to generate heat for heating.

7. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 3), heating is performed by a high temperature electric furnace or plasma.

8. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 3), the heating temperature is 1600-1800°C.

9. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 3), the mass ratio of the specially prepared titanium tetrachloride to oxygen is 5.93-20.

0.

10. The method for preparing high-activity titanium dioxide from tailor-made titanium tetrachloride according to claim 1, characterized in that: In step 3), the mass percentage of titanium dioxide converted from potassium chloride to specially prepared titanium tetrachloride is 0.002-0.005%.

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