Catalytic organic additive, its preparation method and application

Abstract

This invention belongs to the field of high-purity titanium tetrachloride refining technology, specifically relating to a catalytic organic additive, its preparation method, and its application. The catalytic organic additive is composed of organic base oil, alkanes, cycloalkanes, aromatics, and metal oxides in a specific mass ratio, with the following mass ratios: 40–70: 2–10: 10–40: 5–10: 2–10; wherein the organic base oil is glycerol, the alkanes are naphtha, the cycloalkanes are cyclohexane, the aromatics are C9 aromatics, and the metal oxide is alumina. This invention enables the organic additive to possess excellent catalytic cracking performance; in the vanadium removal process of high-vanadium titanium tetrachloride, it can rapidly react with vanadium compounds, significantly improving vanadium removal efficiency while greatly reducing the unit dosage of the organic additive used for vanadium removal. It combines process applicability and economy, and is suitable for the refining stage of high-vanadium titanium tetrachloride in the production of titanium dioxide and sponge titanium.

Description

Technical Field

[0001] This invention belongs to the field of high-purity titanium tetrachloride refining technology, specifically relating to a catalytic organic additive and its preparation method and application, applicable to the deep purification process of titanium tetrachloride in titanium dioxide production, sponge titanium smelting and aerospace titanium alloy raw material pretreatment. Background Technology

[0002] With rapid economic development, the demand for high-purity titanium tetrachloride from industries such as titanium dioxide, sponge titanium, and aerospace titanium alloys has increased dramatically. However, the existing domestic production capacity and quality of high-purity titanium tetrachloride cannot fully meet market demand, especially in the refining stage of titanium tetrachloride prepared by the chloride process. The efficiency and effectiveness of the vanadium removal process have become a key bottleneck restricting product quality. Currently, in the refining process of titanium tetrachloride prepared by the chloride process, the conventional process requires mixing crude titanium tetrachloride with an organic vanadium removal reagent, followed by 70-90 minutes of distillation to remove vanadium impurities. However, existing organic vanadium removal reagents generally suffer from insufficient vanadium removal efficiency, making them unsuitable for processing crude titanium tetrachloride with high vanadium content (e.g., vanadium content ≥ 0.15%), thus limiting the improvement of titanium dioxide production efficiency by the chloride process. Therefore, developing a highly efficient vanadium removal agent suitable for high-vanadium-content titanium tetrachloride has become an urgent technical need to be addressed in the industry. Existing technologies have explored relevant vanadium removal solutions, as detailed below:

[0003] Reference 1 (application number: 201610585009.2) discloses a method for removing vanadium from crude titanium tetrachloride, which involves "first contact between crude titanium tetrachloride and an organic vanadium removal reagent - solid-liquid separation - ...

[0004] The two-step process of "vanadium removal from liquid-phase aluminum powder" treats crude titanium tetrachloride with a vanadium content of 0.3% by weight or higher, claiming to utilize existing aluminum powder vanadium removal equipment, reduce residue, and improve solid settling performance. However, this method relies on subsequent aluminum powder vanadium removal processes and cannot achieve efficient vanadium removal using organic reagents alone; the process steps are relatively complex.

[0005] Reference 2 (Xu Shulin. Study on vanadium removal and purification of TiCl4 by organic compounds [J]. Iron and Steel Vanadium Titanium, 201X, 3X(3):28-33) discloses an organic vanadium removal reagent (SP reagent). By studying the effects of reaction time, reaction temperature and reagent dosage on the vanadium removal effect of TiCl4, the SP reagent with "low dosage and good purification effect" was screened. However, this reference does not clarify the applicability of the reagent in high vanadium content titanium tetrachloride (such as vanadium content ≥0.15%), and does not provide vanadium removal stability data for long-cycle reactions (such as more than 70 min);

[0006] Reference 3 (Yu Jing, Zhang Ping, Chen Tianxiang. Study on vanadium removal process of organic matter in crude titanium tetrachloride [J]. Journal of Guizhou University of Technology (Natural Science Edition), 201X, 37(2):29-32) proposes an organic vanadium removal process for crude TiCl4 in sponge titanium production. By comparing the vanadium removal effects of different organic reagents, it is determined that the self-made NR reagent has the advantages of "good vanadium removal effect, low dosage and low cost", which can make the vanadium content of refined TiCl4 ≤0.0005%, colorimetric value ≤5mgK2Cr2O7 / L, and TiCl4 content ≥99.9%. However, the vanadium removal efficiency of this process is still limited by the reaction time, and the problem of conventional reagents requiring a long reaction time (such as 90min) to achieve the standard has not been solved.

[0007] To further clarify the technical deficiencies of existing organic vanadium removal reagents, the inventors conducted a comparative study on the vanadium removal organic reagents described in the aforementioned literature. The three reagents were numbered 1 (reagent corresponding to Literature 1), 2 (SP reagent of Literature 2), and 3 (NR reagent of Literature 3), respectively. The vanadium removal effect of different reaction times on high-vanadium-content titanium tetrachloride (raw material vanadium content 0.18 wt%) was investigated experimentally. The experimental results are shown in the table below:

[0008] Table 1. Vanadium content in refined titanium at different reaction times.

[0009] sample Vanadium content (ppm) over 50 minutes Vanadium content (ppm) over 60 minutes Vanadium content (ppm) over 70 minutes Vanadium content (ppm) over 90 minutes 1 / 1336 / 1457 2 25 19 17 1 3 80 45 32 13

[0010] According to Table 1, in the vanadium removal experiments conducted by the three organic vanadium removal reagents, only samples 2 and 3 met the standard requirements for vanadium content in refined titanium within 90 minutes.

[0011] In summary, existing vanadium removal organic reagents generally suffer from long reaction cycles (requiring more than 90 minutes to achieve the target) and poor adaptability to high vanadium content, resulting in low production efficiency of the titanium tetrachloride refining process via the chloride method. This makes it difficult to meet the demands of large-scale industrial production for short-cycle and efficient vanadium removal. Therefore, developing a catalytic organic additive that can shorten the reaction time and improve the vanadium removal efficiency of high-vanadium-content titanium tetrachloride has significant technological and industrial value. Summary of the Invention

[0012] The present invention aims to overcome the shortcomings of the prior art and provide a catalytic organic additive with efficient catalytic cracking and vanadium capture functions and its preparation method. It can achieve good dispersion, suitable cracking temperature and high catalytic activity of the additive in titanium tetrachloride, and finally achieve the purpose of efficient vanadium removal at a low dosage and in a short time.

[0013] To solve the above-mentioned technical problems, the present invention is implemented as follows:

[0014] A catalytic organic compound catalytic agent, comprising, by mass ratio:

[0015] Organic base oil 40-70;

[0016] Alkanes 2-10;

[0017] Cycloalkanes 10–40;

[0018] Aromatic hydrocarbons 5-10;

[0019] Metal oxides 2 to 10;

[0020] Wherein, the organic base oil is glycerol; the alkane is naphtha; the cycloalkane is cyclohexane; the aromatic hydrocarbon is C9 aromatic hydrocarbon; and the metal oxide is aluminum oxide.

[0021] Furthermore, the alumina is γ-type alumina with a specific surface area ≥180 m². 2 / g, average particle size 1-3μm, pore size distribution 2-5nm.

[0022] Furthermore, the C9 aromatic hydrocarbon has a distillation range of 160–190°C, a purity of ≥95%, and a moisture content of ≤0.1%.

[0023] Furthermore, the glycerol is food-grade anhydrous glycerol with a purity ≥99.5%, a moisture content ≤0.3%, and a total heavy metal content ≤10μg / kg.

[0024] Furthermore, the naphtha is a straight-run naphtha with a distillation range of 80–180°C, a sulfur content ≤10 mg / kg, and an olefin content ≤0.5%.

[0025] A method for preparing the above-mentioned catalytic organic catalytic agent includes the following steps:

[0026] S1: Glycerol and C9 aromatics are mixed in a certain proportion and dispersed at high speed to obtain mixture A;

[0027] S2: Add naphtha and cyclohexane to mixture A and continue dispersing;

[0028] S3: Add alumina powder and zinc chloride co-catalyst, and disperse to obtain mixture B;

[0029] S4: Heat mixture B to 100-140°C, add dimethylaniline and dimethyl silicone oil, stir and react, then gradually cool to room temperature to obtain the target product, catalytic organic auxiliary agent.

[0030] Further, in step S1, after glycerol is mixed with C9 aromatics, the uniformity of the mixture is detected by a UV spectrophotometer. The dispersion conditions are a rotation speed of 6000-12000 r / min, a time of 120-300 min, and an absorbance variation coefficient ≤3%.

[0031] Furthermore, in step S2, the mass fractions of naphtha and cyclohexane added are 15 wt% and 10 wt%, respectively.

[0032] Further, in step S3, alumina powder and zinc chloride powder are added at an amount of 0.5% of the glycerol mass, and the dispersion conditions are a temperature of 25-35℃, a rotation speed of 8000 r / min, and a time of 100 min.

[0033] Further, in step S4, the amount of dimethylaniline added is 1.2 to 1.8% of the total mass of mixture B; the amount of dimethyl silicone oil added is 0.8 to 1.2% of the total mass of mixture B; the reaction conditions are 80 r / min rotation speed, 60 min time, 100 to 140℃ temperature, and atmospheric pressure.

[0034] The present invention also provides an application of the above-mentioned catalytic organic additive in the vanadium removal process of titanium tetrachloride refining, for treating titanium tetrachloride with a vanadium content ≥0.15%, with a vanadium removal efficiency ≥98.5% and an additive unit dosage ≤0.8 kg / t.

[0035] The catalytic organic additive of this invention exhibits significant advantages in the crude titanium tetrachloride vanadium removal process through component synergy and catalytic enhancement design, as detailed below:

[0036] 1. Compared with existing technologies (such as SP reagent in Reference 2 and NR reagent in Reference 3), the mass ratio of the additive to crude titanium tetrachloride in this invention is reduced from the conventional 1:100 (i.e. 10 kg / t) to 1:800 (i.e. below 1.25 kg / t), and the dosage is reduced by more than 87.5%. This improvement is due to the synergistic dispersing effect of naphtha and cyclohexane, which can promote the uniform dispersion of base oils such as glycerol in titanium tetrachloride, avoid reagent waste caused by excessively high local concentrations, and significantly reduce the company's additive procurement and operating costs.

[0037] 2. The alumina in the additive of this invention can serve as a catalytic active center to accelerate the cracking reaction of carbon sources (glycerol, C9 aromatics) and generate highly active carbon particles. At the same time, the C9 aromatics enhance the reactivity with vanadium compounds, enabling the carbon generated by cracking to quickly undergo a catalytic reduction reaction with vanadium compounds (such as VOCl3) in titanium tetrachloride, converting vanadium into solid vanadium compounds (such as V2C).

[0038] Experimental verification: When crude titanium tetrachloride with a vanadium content of 0.18wt% is treated with the additive of this invention, the vanadium content in titanium tetrachloride can be reduced to ≤1ppm in only 40-50 minutes at a conventional distillation temperature (300℃), which is much lower than the reaction cycle of 90 minutes in the prior art. Moreover, the vanadium removal efficiency is stably maintained at ≥99.5%, which fully meets the vanadium content requirement (≤15ppm) of high-purity titanium tetrachloride.

[0039] 3. The carbon particles generated by the pyrolysis of the additives of this invention have a unique mesh structure (pore size 5-10 nm), and their adsorption capacity for vanadium compounds is significantly better than that of amorphous carbon generated by conventional reagents. The mesh structure can form a dual effect of physical encapsulation and chemical adsorption, which significantly reduces the desorption of vanadium compounds on the carbon surface.

[0040] Experiments show that in the titanium tetrachloride refining process that runs continuously for 100 hours, the vanadium content of titanium tetrachloride can be kept at <1ppm without significant fluctuations. This effectively avoids process downtime caused by unstable vanadium removal, ensures stable product quality, and increases the annual effective production time of the equipment.

[0041] 4. The pyrolysis temperature (280-320°C) of the additive of this invention is perfectly matched with the process temperature window of the existing titanium tetrachloride refining process by chloride method. It does not require modification of existing distillation equipment and mixing equipment, and can directly replace existing vanadium removal reagents, reducing the equipment modification investment of enterprises and having extremely strong feasibility for industrial application. Attached Figure Description

[0042] Figure 1 XPS C1S spectrum of the residue;

[0043] Figure 2 Scanning micrographs of the residue;

[0044] Figure 3 High-power scanning microscope image of the residue;

[0045] Figure 4 This is a high-magnification scanning microscope image of the residue. Detailed Implementation

[0046] The present invention will now be described in detail through specific embodiments. These embodiments are provided to enable a more thorough understanding of the invention and to fully convey the scope of the invention to those skilled in the art. As used throughout the specification and claims, the terms "comprising" or "including" are open-ended and are interpreted as "comprising but not limited to". The following description describes preferred embodiments for carrying out the invention; however, this description is intended to follow the general principles of the specification and is not intended to limit the scope of the invention.

[0047] Example 1

[0048] (1) Glycerol and C9 aromatics were mixed in a ratio of 3:1 and placed in a sealed high-speed disperser. The mixture was stirred for 180 min at a speed of 6000 r / min to obtain mixture A.

[0049] (2) The uniformity of mixing of mixture A was tested by ultraviolet spectrophotometer. The test results showed that its absorbance variation coefficient was >3%, which did not meet the dispersion requirements.

[0050] Example 2

[0051] (1) Glycerol and C9 aromatics were mixed in a ratio of 2:1 and placed in a sealed high-speed disperser. The mixture was stirred for 180 min at a speed of 6000 r / min to obtain mixture A.

[0052] (2) The uniformity of mixing of mixture A was tested by ultraviolet spectrophotometer. The test results showed that its absorbance variation coefficient was >3%, which did not meet the dispersion requirements.

[0053] Example 3

[0054] (1) Glycerol and C9 aromatics were mixed in a 1:1 ratio and placed in a sealed high-speed disperser. The mixture was stirred for 180 min at a speed of 6000 r / min to obtain mixture A.

[0055] (2) The uniformity of mixing of mixture A was tested by ultraviolet spectrophotometer. The test results showed that its absorbance variation coefficient was 3%, which did not meet the dispersion requirements.

[0056] Example 4

[0057] (1) Glycerol and C9 aromatics were mixed in a 1:1 ratio and placed in a sealed high-speed disperser. The mixture was stirred for 260 min at a speed of 10000 r / min to obtain mixture A.

[0058] (2) The uniformity of mixing of mixture A was tested by ultraviolet spectrophotometer. The test results showed that its absorbance variation coefficient was ≤3%, which met the dispersion requirements.

[0059] Example 5

[0060] (1) Glycerol and C9 aromatics were mixed in a 1:1 ratio and placed in a sealed high-speed disperser. The mixture was stirred for 260 min at a speed of 10000 r / min to obtain mixture A.

[0061] (2) Add 15wt% naphtha and 10wt% cyclohexane to step (1) and continue to disperse in a high-speed disperser with the parameters in step (1);

[0062] (3) Add alumina powder and anhydrous zinc chloride powder to step (2), the amount added is 0.5% of the mass of glycerol, the dispersion conditions are temperature 25-35 ℃, rotation speed 8000 r / min, time 100 min, to obtain mixture B;

[0063] (4) Heat the mixture B obtained in step (3) to 120°C, add dimethylaniline and dimethyl silicone oil in proportion, the amount of dimethylaniline added is 1.2% of the total mass of mixture B; the amount of dimethyl silicone oil added is 0.8% of the total mass of mixture B, and stir at 80 r / min for 60 min;

[0064] (5) Gradual cooling above 75℃ at a rate of 1℃ / 5min, followed by natural cooling to room temperature below 75℃ to obtain the target product, thus removing the catalytic organic auxiliaries of titanium tetrachloride with high vanadium content.

[0065] Experimental results show that the viscosity of the catalytic organic additive is within the viscosity range suitable for industrial applications. However, its dispersion effect is poor; when used to treat titanium tetrachloride with a vanadium content ≥0.15%, the vanadium removal efficiency is ≥90%.

[0066] Table 2. Physical properties of each component in the compounded organic compound

[0067] glycerin naphtha Cyclohexane <![CDATA[C9 Aromatics]]> Alumina Zinc chloride Appearance liquid liquid liquid liquid powder powder <![CDATA[Density (g / cm 3 ).]]> 1.26331 0.76 0.78 0.97-1.04 3.97 2.91 refractive index 1.473 1.428 1.426 1.512 - - Flash point (°C) 177 35-38 -18 -18--20 - - Kinematic viscosity at room temperature (mm² / s) <![CDATA[1.19×10 -3 ]]> 552.6 1155.1 2.25 - -

[0068] Example 6

[0069] (1) Glycerol and C9 aromatics were mixed in a 1:1 ratio and placed in a sealed high-speed disperser. The mixture was stirred for 260 min at a speed of 10000 r / min to obtain mixture A.

[0070] (2) Add 15wt% naphtha and 10wt% cyclohexane to step (1) and continue to disperse in a high-speed disperser with the parameters in step (1);

[0071] (3) Add alumina powder and anhydrous zinc chloride powder to step (2), the amount added is 0.5% of the mass of glycerol, the dispersion conditions are temperature 25~35℃, rotation speed 8000r / min, time 100min, to obtain mixture B;

[0072] (4) Heat the mixture B obtained in step (3) to 120°C, add dimethylaniline and dimethyl silicone oil in proportion, the amount of dimethylaniline added is 1.5% of the total mass of mixture B; the amount of dimethyl silicone oil added is 1.0% of the total mass of mixture B, and stir at 80 r / min for 60 min;

[0073] (5) Gradual cooling above 75℃ at a rate of 1℃ / 5min, followed by natural cooling to room temperature below 75℃ to obtain the target product, thus removing the catalytic organic auxiliaries of titanium tetrachloride with high vanadium content.

[0074] Table 3 Comparison of Effects of Examples 5 and 6

[0075] Example 5 Example 6 Dispersion effect: Poor Dispersion effect: Good Vanadium removal efficiency ≥ 90% Vanadium removal efficiency ≥ 95%

[0076] Example 7

[0077] (1) Glycerol and C9 aromatics were mixed in a 1:1 ratio and placed in a sealed high-speed disperser. The mixture was stirred for 260 min at a speed of 10000 r / min to obtain mixture A.

[0078] (2) Add 15 wt% naphtha and 10 wt% cyclohexane to step (1) and continue to disperse in a high-speed disperser with the parameters in step (1);

[0079] (3) Add alumina powder and anhydrous zinc chloride powder to step (2), the amount added is 0.5% of the mass of glycerol, the dispersion conditions are temperature 25~35℃, rotation speed 8000r / min, time 100min, to obtain mixture B;

[0080] (4) Heat the mixture B obtained in step (3) to 120°C, add dimethylaniline and dimethyl silicone oil in proportion, the amount of dimethylaniline added is 1.8% of the total mass of mixture B; the amount of dimethyl silicone oil added is 1.2% of the total mass of mixture B, and stir at 80 r / min for 60 min;

[0081] (5) Gradual cooling above 75℃ at a rate of 1℃ / 5min, followed by natural cooling to room temperature below 75℃ to obtain the target product, thus removing the catalytic organic auxiliaries of titanium tetrachloride with high vanadium content.

[0082] Table 4 Comparison of Effects of Examples 6 and 7

[0083] Example 6 Example 7 Dispersion effect: good Dispersion effect: Good Vanadium removal efficiency ≥ 95% Vanadium removal efficiency ≥ 98.5%

[0084] The organic compound prepared according to the above optimal compound ratio was used to refine titanium tetrachloride. Refined titanium samples were collected at distillation times of 50 min, 60 min, 70 min, and 90 min, and the vanadium content was determined. The refined titanium samples collected in the examples were analyzed, and the experimental results are shown in Table 5.

[0085] Table 5. Vanadium content in refined titanium after vanadium removal from compounded organic materials.

[0086] sample 200:1 (ppm) 400:1 (ppm) 600:1 (ppm) 800:1 (ppm) Example 5 ＜1 ＜1 ＜1 14 Example 6 ＜1 ＜1 ＜1 17 Example 7 ＜1 ＜1 2 20 control sample 18 - - -

[0087] As can be seen from the examples and control samples, when achieving the same vanadium removal efficiency, the method for preparing a catalytic organic additive for removing high-vanadium titanium tetrachloride provided by the present invention can effectively reduce the initial addition amount of organic vanadium removal reagent (200:1 to 800:1), thereby achieving the goal of reducing industrial costs.

[0088] It is understood that those skilled in the art can make various other corresponding changes and modifications based on the technical concept of this invention, and all such changes and modifications should fall within the protection scope of the claims of this invention.

Claims

1. A catalyst for organic compounds, characterized in that, In terms of mass ratio, it includes: Organic base oil 40-70; Alkanes 2-10; Cycloalkanes 10–40; Aromatic hydrocarbons 5-10; Metal oxides 2 to 10; Wherein, the organic base oil is glycerol; the alkane is naphtha; the cycloalkane is cyclohexane; the aromatic hydrocarbon is C9 aromatic hydrocarbon; and the metal oxide is aluminum oxide.

2. The catalytic organic compound catalytic agent according to claim 1, characterized in that, The alumina is γ-type alumina with a specific surface area ≥180 m². 2 / g, average particle size 1-3μm, pore size distribution 2-5nm.

3. The catalytic organic compound catalytic agent according to claim 2, characterized in that, The C9 aromatic hydrocarbon has a distillation range of 160–190°C, a purity of ≥95%, and a moisture content of ≤0.1%.

4. The catalytic organic compound catalytic agent according to claim 3, characterized in that, The glycerol is food-grade anhydrous glycerol with a purity ≥99.5%, a moisture content ≤0.3%, and a total heavy metal content ≤10μg / kg.

5. The catalytic organic compound catalytic agent according to claim 4, characterized in that, The naphtha is a straight-run naphtha with a distillation range of 80–180°C, a sulfur content of ≤10 mg / kg, and an olefin content of ≤0.5%.

6. A method for preparing a catalytic organic catalytic agent as described in any one of claims 1 to 5, characterized in that, The specific steps include the following: S1: Glycerol and C9 aromatics are mixed in a certain proportion and dispersed at high speed to obtain mixture A; S2: Add naphtha and cyclohexane to mixture A and continue dispersing; S3: Add alumina powder and zinc chloride co-catalyst, and disperse to obtain mixture B; S4: Heat mixture B to 100-140°C, add dimethylaniline and dimethyl silicone oil, stir and react, then gradually cool to room temperature to obtain the target product, catalytic organic auxiliary agent.

7. The method for preparing the catalytic organic catalytic agent according to claim 6, characterized in that, In step S1, after glycerol and C9 aromatics are mixed, the uniformity of the mixture is detected by a UV spectrophotometer. The dispersion conditions are a rotation speed of 6000-12000 r / min, a time of 120-300 min, and an absorbance variation coefficient ≤3%.

8. The method for preparing the catalytic organic catalytic agent according to claim 6, characterized in that, In step S2, the mass fractions of naphtha and cyclohexane added are 15 wt% and 10 wt%, respectively.

9. The method for preparing the catalytic organic catalytic agent according to claim 6, characterized in that, In step S3, the zinc chloride is analytical grade anhydrous zinc chloride, and the amount of alumina and anhydrous zinc chloride added is 0.5% of the mass of glycerol. The dispersion conditions are a temperature of 25-35℃, a rotation speed of 8000 r / min, and a time of 100 min.

10. The method for preparing the catalytic organic catalytic agent according to claim 8, characterized in that, In step S4, the amount of dimethylaniline added is 1.2 to 1.8% of the total mass of mixture B; the amount of dimethyl silicone oil added is 0.8 to 1.2% of the total mass of mixture B; the reaction conditions are 80 r / min rotation speed, 60 min time, 100 to 140℃ temperature, and atmospheric pressure.

11. The application of the catalytic organic additive according to any one of claims 1 to 5 in the vanadium removal process of titanium tetrachloride refining, characterized in that, It is used to treat titanium tetrachloride with a vanadium content ≥0.15%, with a vanadium removal efficiency ≥98.5% and an additive dosage ≤0.8 kg / t.

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