阅读说明：本技术 一种可连续生产四氯化钛晶种的方法 (Method for continuously producing titanium tetrachloride crystal seeds ) 是由 陈宇 李炳亮 于 2021-02-22 设计创作，主要内容包括：本发明公开了一种可连续生产四氯化钛晶种的方法,步骤包括：(1)晶种稀释：首先将需要稀释的四氯化钛通过换热器将温度控制在40℃以下,随后将四氯化钛输入稀释槽中稀释,稀释后的四氯化钛用于储存,分批次的往制备槽送料；(2)晶种制备：稀释后的四氯化钛溶液与氢氧化钠溶液进行反应,用四氯化钛溶液与碱液和水进行快速混合,完成中和反应；(3)晶种沉降：将制备完成的晶种悬浮液洗涤,让晶种析出后进行沉降,沉降之后,将其中包含了大量中和产生的可溶性盐的上层清液排掉；(4)晶种储存：将上层清液排完后,沉降的晶种需要进行搅拌,之后泵到储槽进行储存。本发明提供的生产四氯化钛晶种的方法简单高效,能够实现连续化生产。(The invention discloses a method for continuously producing titanium tetrachloride crystal seeds, which comprises the following steps: (1) seed crystal dilution: firstly, controlling the temperature of titanium tetrachloride to be diluted to be below 40 ℃ through a heat exchanger, then inputting the titanium tetrachloride into a dilution tank for dilution, storing the diluted titanium tetrachloride, and feeding the titanium tetrachloride to a preparation tank in batches; (2) preparing seed crystals: reacting the diluted titanium tetrachloride solution with a sodium hydroxide solution, and quickly mixing the titanium tetrachloride solution with alkali liquor and water to complete a neutralization reaction; (3) seed crystal sedimentation: washing the prepared seed crystal suspension, precipitating the seed crystal, and then discharging supernatant containing a large amount of soluble salts generated by neutralization; (4) seed crystal storage: after the supernatant is discharged, the settled seed crystals need to be stirred, and then pumped to a storage tank for storage. The method for producing the titanium tetrachloride seed crystal is simple and efficient, and can realize continuous production.)

1. A method for continuously producing titanium tetrachloride seed crystals, which is characterized by comprising the following steps:

(1) seed crystal dilution: firstly, controlling the temperature of titanium tetrachloride to be diluted to be below 40 ℃ through a heat exchanger, then inputting the titanium tetrachloride into a dilution tank for dilution, storing the diluted titanium tetrachloride, and feeding the titanium tetrachloride to a preparation tank in batches;

(2) preparing seed crystals: reacting the diluted titanium tetrachloride solution with a sodium hydroxide solution, and quickly mixing the titanium tetrachloride solution with alkali liquor and water to complete a neutralization reaction;

(3) seed crystal sedimentation: washing the prepared seed crystal suspension with hot water at 40-100 ℃, precipitating the seed crystal, and then, discharging supernatant containing a large amount of soluble salts generated by neutralization;

(4) seed crystal storage: after the supernatant is discharged, the settled seed crystals need to be stirred, and then pumped to a storage tank for storage.

2. A process for continuously producing titanium tetrachloride seed crystals as claimed in claim 1, wherein the pH after the neutralization reaction in the step (2) is 5 to 6.

3. A method for continuously producing titanium tetrachloride seed crystals as claimed in claim 1, wherein the concentration of the sodium hydroxide solution in the step (2) is 4-10% by mass.

4. A process for continuously producing titanium tetrachloride seed crystals as claimed in claim 1, wherein the volume ratio of the titanium tetrachloride solution, the alkali solution and the water in the step (2) is (15-27): (10-12): (26-32).

5. A process for continuously producing titanium tetrachloride seed crystals as claimed in claim 1, wherein the concentration of the precipitate in the step (3) is controlled to be 30 to 50 g/l.

6. A process for continuously producing titanium tetrachloride seed crystals as claimed in claim 1, wherein the settling time in the step (3) is not less than 1.5 hours.

Technical Field

The invention belongs to the technical field of titanium tetrachloride production, and particularly relates to a method for continuously producing titanium tetrachloride crystal seeds.

Background

Titanium tetrachloride is a colorless dense liquid, and samples are impure and often yellow or reddish brown. Similar to vanadium tetrachloride, it belongs to one of the few transition metal chlorides that are liquid at room temperature, and its low melting point is associated with weak intermolecular forces. Most metal chlorides are polymers containing metal atoms attached by chlorine bridges, whereas the intermolecular forces of titanium tetrachloride are mainly weak van der waals forces and therefore the melting point is not high.

TiCl₄The molecule is of tetrahedral structure, each Ti⁴⁺With four ligands Cl^-Are connected. Ti⁴⁺Has the same electron number as that of rare gas argon and is of a closed shell structure. Therefore, the titanium tetrachloride molecule is of a regular tetrahedron structure and has high symmetry.

TiCl₄Soluble in nonpolar toluene and chlorinated hydrocarbons. Titanium tetrachloride may react exothermically with lewis base solvents (e.g., THF) to form a hexacoordinated adduct. For bulky ligands, the product is a penta-coordinated TiCl₄And L. In addition to releasing corrosive hydrogen chloride, titanium oxide and chlorine oxide are formed when TiCl4 is stored and stick to used stoppers and syringes.

At present, patent CN101863510B provides a method for preparing titanium dioxide hydrolysis seed crystal, which comprises the following steps: a. adding a TiCl4 aqueous solution into an alkaline solution, and neutralizing the pH value of the alkaline solution to 0-2; wherein the concentration of the TiCl4 aqueous solution is 200-450 g/L in terms of TiO 2; b. uniformly stirring the slurry obtained by neutralization, heating to 60-90 ℃, and keeping the temperature for 0-90 min; c. cooling the slurry to room temperature to obtain titanium white and hydrolysis crystal seeds; therefore, the improvement of the production efficiency is of great significance. Based on the above statement, the present invention proposes a method for continuously producing titanium tetrachloride seed crystals.

Disclosure of Invention

The invention aims to provide a method for continuously producing titanium tetrachloride seed crystals, which is simple and efficient and can realize continuous production of titanium tetrachloride.

A process for continuously producing titanium tetrachloride seed crystals, comprising the steps of:

(1) seed crystal dilution: firstly, controlling the temperature of titanium tetrachloride to be diluted to be below 40 ℃ through a heat exchanger, then inputting the titanium tetrachloride into a dilution tank for dilution, storing the diluted titanium tetrachloride, and feeding the titanium tetrachloride to a preparation tank in batches;

(2) preparing seed crystals: reacting the diluted titanium tetrachloride solution with a sodium hydroxide solution, and quickly mixing the titanium tetrachloride solution with alkali liquor and water to complete a neutralization reaction;

(3) seed crystal sedimentation: washing the prepared seed crystal suspension with hot water at 40-100 ℃, precipitating the seed crystal, and then, discharging supernatant containing a large amount of soluble salts generated by neutralization;

(4) seed crystal storage: after the supernatant is discharged, the settled seed crystals need to be stirred, and then pumped to a storage tank for storage.

Preferably, the pH value after the neutralization reaction in the step (2) is 5 to 6.

Preferably, the mass percentage concentration of the sodium hydroxide solution in the step (2) is 4-10%.

Preferably, the volume ratio of the titanium tetrachloride solution to the alkali liquor to the water in the step (2) is (15-27): (10-12): (26-32).

Preferably, the concentration of the sediment in the step (3) is controlled to be 30-50 g/L.

Preferably, the settling time in the step (3) is not less than 1.5 h.

The method for continuously producing the titanium tetrachloride seed crystal, which is provided by the invention, has the following beneficial effects:

1. the method comprises the steps of seed crystal dilution, seed crystal preparation, seed crystal sedimentation and seed crystal storage to realize continuous production of the titanium tetrachloride seed crystal, is simple and efficient, controls the temperature of the titanium tetrachloride to be diluted to be below 40 ℃ through a heat exchanger, and then inputs the titanium tetrachloride into a dilution tank for dilution to improve the dilution efficiency;

2. in the seed crystal preparation step of the invention, the volume ratio of the titanium tetrachloride solution, the alkali liquor and the water is (15-27): (10-12): (26-32), completing the neutralization reaction after uniform mixing, wherein the pH value after the neutralization reaction is 5-6, improving the yield and realizing continuous production.

Detailed Description

The technical solutions of the present invention are further described below with reference to specific examples, but those skilled in the art will understand that the following examples are only for illustrating how to use the present invention, and should not be construed as limiting the scope of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The word "embodiment" as used herein, is not necessarily to be construed as preferred or advantageous over other embodiments, including any embodiment illustrated as "exemplary". The performance indexes in the method examples are tested by adopting a conventional test method in the field unless otherwise specified, and the test conditions are common experimental conditions.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The composition and content of the water, such as the content of impurities, etc., in the water according to the present invention are in accordance with the national standard for industrial water. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The units indicating the content of the raw materials are all in parts by mass. Other raw materials as used in the present invention all refer to raw materials commonly used in the art. In addition, the measurement methods of the technical indexes of the invention are all standard methods used in the field, and the latest national standard can be specifically referred to.

The technical means used in the following examples are conventional means well known to those skilled in the art, and all raw materials are general-purpose materials.

Example 1

The embodiment provides a method for continuously producing titanium tetrachloride seed crystals, which comprises the following steps:

(1) seed crystal dilution: firstly, controlling the temperature of titanium tetrachloride to be diluted to be below 40 ℃ through a heat exchanger, then inputting the titanium tetrachloride into a dilution tank for dilution, storing the diluted titanium tetrachloride, and feeding the titanium tetrachloride to a preparation tank in batches;

(2) preparing seed crystals: reacting the diluted titanium tetrachloride solution with a sodium hydroxide solution, and quickly mixing the titanium tetrachloride solution with alkali liquor and water to complete a neutralization reaction;

(3) seed crystal sedimentation: washing the prepared seed crystal suspension with hot water at 40 ℃, precipitating the seed crystal, and then discharging supernatant containing a large amount of soluble salts generated by neutralization;

(4) seed crystal storage: after the supernatant is discharged, the settled seed crystals need to be stirred, and then pumped to a storage tank for storage.

The pH value after the neutralization reaction in the step (2) is 5; preferably, the concentration of the sodium hydroxide solution in the step (2) is 4% by mass; the volume ratio of the titanium tetrachloride solution to the alkali liquor to the water in the step (2) is (15): (10): (26) (ii) a The concentration of the sediment in the step (3) is controlled to be 30 g/L; the settling time in the step (3) is 1.5 h.

Example 2

The embodiment provides a method for continuously producing titanium tetrachloride seed crystals, which comprises the following steps:

(1) seed crystal dilution: firstly, controlling the temperature of titanium tetrachloride to be diluted to be below 40 ℃ through a heat exchanger, then inputting the titanium tetrachloride into a dilution tank for dilution, storing the diluted titanium tetrachloride, and feeding the titanium tetrachloride to a preparation tank in batches;

(2) preparing seed crystals: reacting the diluted titanium tetrachloride solution with a sodium hydroxide solution, and quickly mixing the titanium tetrachloride solution with alkali liquor and water to complete a neutralization reaction;

(3) seed crystal sedimentation: washing the prepared seed crystal suspension with hot water at 70 ℃, precipitating the seed crystal, and then discharging supernatant containing a large amount of soluble salts generated by neutralization;

(4) seed crystal storage: after the supernatant is discharged, the settled seed crystals need to be stirred, and then pumped to a storage tank for storage.

The pH value after the neutralization reaction in the step (2) is 5.5; preferably, the concentration of the sodium hydroxide solution in the step (2) is 7% by mass; preferably, the volume ratio of the titanium tetrachloride solution, the alkali liquor and the water in the step (2) is (20): (11): (29) (ii) a The concentration of the sediment in the step (3) is controlled to be 40 g/L; the settling time in the step (3) is not less than 1.5 h.

Example 3

The embodiment provides a method for continuously producing titanium tetrachloride seed crystals, which comprises the following steps:

(1) seed crystal dilution: firstly, controlling the temperature of titanium tetrachloride to be diluted to be below 40 ℃ through a heat exchanger, then inputting the titanium tetrachloride into a dilution tank for dilution, storing the diluted titanium tetrachloride, and feeding the titanium tetrachloride to a preparation tank in batches;

(2) preparing seed crystals: reacting the diluted titanium tetrachloride solution with a sodium hydroxide solution, and quickly mixing the titanium tetrachloride solution with alkali liquor and water to complete a neutralization reaction;

(3) seed crystal sedimentation: washing the prepared seed crystal suspension with hot water at 100 ℃, precipitating the seed crystal, and then discharging supernatant containing a large amount of soluble salts generated by neutralization;

(4) seed crystal storage: after the supernatant is discharged, the settled seed crystals need to be stirred, and then pumped to a storage tank for storage.

The pH value after the neutralization reaction in the step (2) is 6; the mass percentage concentration of the sodium hydroxide solution in the step (2) is 10 percent; the volume ratio of the titanium tetrachloride solution to the alkali liquor to the water in the step (2) is (27): (12): (32) (ii) a The concentration of the sediment in the step (3) is controlled to be 50 g/L; the settling time in the step (3) is not less than 1.5 h.

Comparative example 1

Different from the example 1, the volume ratio of the titanium tetrachloride solution, the alkali liquor and the water in the step (2) is 30: 15: 45.

comparative example 2

Unlike example 1, the concentration of the sodium hydroxide solution in step (2) was 13% by mass.

Statistics on the yields obtained in examples 1-3 and comparative examples 1-2 are shown in the following table, which is plotted in Table 1:

	example 1	Example 2	Example 3	Comparative example 1	Comparative example 2
						Yield (%)	89.6	91.3	88.3	50.5	64.3

From the above table, it can be seen that:

the test results of the above examples and comparative examples may reflect: the reaction steps and conditions in examples 1 to 3 can significantly improve the yield, and also can efficiently realize continuous production.

Finally, it should be noted that: the above embodiments are only used to illustrate the present invention and do not limit the technical solutions described in the present invention; it will be understood by those skilled in the art that the present invention may be modified and equivalents may be substituted; all such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims.