CN108190950B - Preparation method of zirconium dioxide - Google Patents

Abstract

The invention discloses a preparation method of zirconium dioxide, which comprises the following steps: 1) heating and sublimating solid zirconium tetrachloride into gaseous zirconium tetrachloride in an evaporator; 2) igniting gaseous zirconium tetrachloride and hydrogen, oxygen or air in a combustor, carrying out combustion reaction to generate solid zirconium dioxide and hydrogen chloride, and obtaining a first mixture after the reaction. According to the preparation method of zirconium dioxide, solid zirconium dioxide is prepared through ignition combustion reaction, so that self-supply of heat in a combustor is realized, energy is saved, and production cost is reduced.

Description

The preparation method of zirconium dioxide

technical field

The invention belongs to the technical field of zirconium dioxide production, and in particular relates to a preparation method of zirconium dioxide.

Background technique

According to different processes, the preparation process of zirconia can be divided into chemical method (wet process) and electrofusion method (dry process). Zirconium oxide is obtained by smelting at a high temperature of 2300°C. The chemical method is to first convert zircon sand into zirconium oxychloride, and then zirconium oxychloride is decomposed at high temperature to form zirconium oxide. The main disadvantage of the electrofusion method is that the product purity is low. At present, the average purity of fused zirconium produced in China is 98.5%, which limits the application of fused zirconia in the field of high-end products. The process of chemically preparing zirconia is complicated, and at the same time, a large amount of waste liquid is generated, and the production cost is high.

The prior art all adopts the method of hydrolysis of zirconium tetrachloride to prepare zirconia, and the process is complicated. Therefore, developing a new method for preparing zirconium dioxide has become a technical barrier that is difficult for those skilled in the art to overcome.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a preparation method of zirconium dioxide for the above-mentioned deficiencies in the prior art, which solves the problems of complicated process and high production cost in the process of preparing zirconium dioxide by traditional chemical method.

The technical scheme adopted to solve the technical problem of the present invention is to provide a preparation method of zirconium dioxide, comprising the following steps:

1) heating and subliming solid zirconium tetrachloride into gaseous zirconium tetrachloride in an evaporator;

2) Ignite gaseous zirconium tetrachloride and hydrogen, oxygen or air in the burner, and generate solid zirconium dioxide and hydrogen chloride through combustion reaction, and obtain the first mixture after the reaction.

Preferably, the temperature in the burner in the step 2) is 500-1000°C.

Preferably, in the step 2), after the ignition reaction, the reaction exotherm keeps the temperature in the burner at 500-1000°C. The temperature in the combustor is controlled to be 500-1000°C by adjusting the intake air amount of oxygen in the combustion reactor.

Preferably, the heating temperature in the evaporator in the step 1) is 400-550°C.

Preferably, the following steps are also included after the step 2):

3) Passing the first mixture into the first dust collector for dust removal, the solid zirconium dioxide in the first mixture is separated, and the separated first dust removal tail gas is obtained.

Preferably, in step 2), when gaseous zirconium tetrachloride, hydrogen and oxygen are ignited in the burner, the number of moles of hydrogen: the number of moles of oxygen: the number of moles of zirconium tetrachloride=(2～2.5): 1: (1 to 1.1). The first mixture includes: zirconium dioxide content (solids), hydrogen chloride, zirconium tetrachloride, hydrogen, traces of oxygen, traces of water vapor.

Preferably, the boiling point of zirconium tetrachloride<the temperature in the first dust collector<the boiling point of zirconium dioxide.

Preferably, the temperature in the first dust collector is 400-1000°C. At normal temperature and pressure, the boiling point of zirconium tetrachloride is 331°C, and the boiling point of zirconium dioxide is 4300°C.

Preferably, after the step 3), the following steps are also included:

4) pass the first dedusting tail gas into the cooler for cooling, and cool the gaseous zirconium tetrachloride in the first dedusting tail gas into solid zirconium tetrachloride to obtain a cooling mixture; the cooling mixture comprises: hydrogen chloride, zirconium tetrachloride , hydrogen, trace oxygen, trace water vapor, trace zirconium dioxide.

5) Passing the cooling mixture into the second dust collector for dust removal, the solid zirconium tetrachloride in the cooling mixture is separated, and the separated second dust removal tail gas is obtained; the second dust removal tail gas includes: hydrogen chloride, hydrogen and trace oxygen.

6) Passing the second dedusting tail gas into the deaerator for deoxygenation to obtain the deaerator tail gas, and the deaerator tail gas includes hydrogen chloride and hydrogen. The tail gas of the deaerator includes: hydrogen chloride and hydrogen.

Preferably, in the step 4), the temperature for cooling through the cooler is 150-220°C.

Preferably, when gaseous zirconium tetrachloride, hydrogen and air are ignited in the burner in step 2), the number of moles of hydrogen: the number of moles of oxygen in the air: the number of moles of zirconium tetrachloride=(2～2.5 ):(1～1.5):1. The first mixture includes: hydrogen chloride, nitrogen, zirconium dioxide (solid), traces of oxygen, traces of water vapor, traces of hydrogen.

Preferably, after the step 3), the following steps are also included:

4) pass the first dedusting tail gas into the absorption tower to absorb hydrogen chloride, obtain the tower still liquid of the absorption tower at the tower still of the absorption tower, obtain the absorption tower tail gas at the tower top of the absorption tower, and vent the absorption tower tail gas; the first dedusting The tail gas includes: hydrogen chloride, nitrogen, oxygen, trace water vapor, trace hydrogen.

The tail gas of the absorption tower includes: nitrogen, oxygen, trace moisture, trace hydrogen.

5) Passing the tower bottom liquid of the absorption tower into the desorption tower to decompose hydrogen chloride, and obtains the desorption tower tail gas at the top of the desorption tower, and the desorption tower tail gas includes hydrogen chloride. The tail gas of the analytical tower includes: hydrogen chloride and water.

Preferably, the step 5) also includes the following steps after:

6) Passing the tower still liquid of the desorption tower and/or the tower still liquid of the absorption tower into the tower top of the absorption tower as the eluent of the absorption tower.

The present invention also provides a preparation device of zirconium dioxide, comprising:

Evaporator for heating and subliming solid zirconium tetrachloride into gaseous zirconium tetrachloride;

The burner is connected to the evaporator, and the burner is used to ignite gaseous zirconium tetrachloride and hydrogen, oxygen or air in the burner, and the combustion reaction generates solid zirconium dioxide and hydrogen chloride, and the first mixture is obtained after the reaction.

Preferably, the device for preparing zirconium dioxide also includes:

The mixer is arranged between the evaporator and the burner, and is connected with the evaporator and the burner respectively, and the mixer is used for mixing the gaseous zirconium tetrachloride and the hydrogen gas passed into it.

Preferably, the burner is provided with a gas distributor for feeding materials into the burner, and the gas distributor includes: an inner ring channel at the center position, a ring-shaped middle ring channel covered on the outside of the inner ring channel, a coating The outer ring channel is annular outside the middle ring channel, the inner ring channel is used for the gaseous mixture of zirconium tetrachloride and hydrogen, the middle ring channel is used for oxygen or air, and the outer ring channel is used for the gaseous tetrachloride A mixture of zirconium and hydrogen.

Preferably, the device for preparing zirconium dioxide also includes:

The first dust collector is connected to the burner, and the first dust collector is used for dust removal of the first mixture passed into it, the solid zirconium dioxide in the first mixture is separated, and the separated first dust removal exhaust gas is obtained.

Preferably, the device for preparing zirconium dioxide also includes:

a cooler, connected with the first dust collector, the cooler is used for cooling the first dust removal tail gas, and cooling the gaseous zirconium tetrachloride into solid zirconium tetrachloride to obtain a cooling mixture;

The second dust collector is connected with the cooler, and the second dust collector is used for dedusting the cooling mixture, the solid zirconium tetrachloride in the cooling mixture is separated, and the separated second dust removal tail gas is obtained;

The deaerator is connected to the second dust collector, and the deaerator is used to deoxygenate the second dust removal tail gas to obtain the deaerator tail gas, and the deaerator tail gas includes hydrogen chloride and hydrogen.

Preferably, the device for preparing zirconium dioxide also includes:

The absorption tower is connected with the first dust collector. The absorption tower is used to adsorb hydrogen chloride on the first dust removal tail gas. The tower kettle liquid of the absorption tower is obtained from the tower kettle of the absorption tower, and the tail gas of the absorption tower is obtained at the top of the absorption tower. The exhaust gas is vented;

The analysis tower is connected with the absorption tower, and the analysis tower is used to analyze the hydrogen chloride in the tower bottom liquid of the absorption tower, and the tail gas of the analysis tower is obtained at the top of the analysis tower, and the tail gas of the analysis tower includes hydrogen chloride.

Preferably, the tower still of the analysis tower is connected with the tower top of the absorption tower, and the tower still liquid of the analysis tower is passed into the tower top of the absorption tower as the eluent of the absorption tower; and/or,

The tower kettle of the absorption tower is connected with the tower top of the absorption tower, and the tower kettle liquid of the absorption tower is passed into the tower top of the absorption tower as the eluent of the absorption tower.

The preparation method of zirconium dioxide in the present invention prepares solid zirconium dioxide through ignition and combustion reaction, and realizes self-sufficiency of heat in the burner, thereby saving energy and reducing production cost.

Description of drawings

Fig. 1 is the structural representation of the preparation device of zirconium dioxide in embodiment 2 of the present invention;

Fig. 2 is the structural representation of the preparation device of zirconium dioxide in embodiment 5 of the present invention;

3 is a front view of the gas distributor in Embodiments 2 and 5 of the present invention;

FIG. 4 is a plan view of the gas distributor in Embodiments 2 and 5 of the present invention.

In the figure: 1-evaporator; 2-mixer; 3-burner; 4-gas distributor; 5-inner ring channel; 6-middle ring channel; 7-outer ring channel; 8-first dust collector; 9- Cooler; 10-Second dust collector; 11-Deaerator; 12-Absorption tower; 13-Tower bottom acid liquid circulation pump; 14-Tower top reflux liquid sprayer; 15-Analysis tower; 16-Heater.

Detailed ways

In order to make those skilled in the art better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

Example 1

The present embodiment provides a preparation method of zirconium dioxide, comprising the following steps:

1) heating and subliming solid zirconium tetrachloride into gaseous zirconium tetrachloride in an evaporator;

2) Ignite gaseous zirconium tetrachloride and hydrogen, oxygen or air in the burner, and generate solid zirconium dioxide and hydrogen chloride through combustion reaction, and obtain the first mixture after the reaction.

The present embodiment also provides a device for preparing zirconium dioxide, comprising:

Evaporator for heating and subliming solid zirconium tetrachloride into gaseous zirconium tetrachloride;

The burner is connected to the evaporator, and the burner is used to ignite gaseous zirconium tetrachloride and hydrogen, oxygen or air in the burner, and the combustion reaction generates solid zirconium dioxide and hydrogen chloride, and the first mixture is obtained after the reaction.

In the preparation method of zirconium dioxide in this embodiment, solid zirconium dioxide is prepared through ignition and combustion reaction, which realizes self-sufficiency of heat in the burner, thereby saving energy and reducing production cost.

Example 2

As shown in FIG. 1, this embodiment also provides a preparation device for zirconium dioxide, including:

The evaporator 1 is used for heating and subliming solid zirconium tetrachloride into gaseous zirconium tetrachloride; specifically, the main material of the evaporator 1 in this embodiment is carbon steel and stainless steel, and the interior of the evaporator 1 is provided with silicon nitride A wear-resistant and high-temperature resistant ceramic lining formed by zirconia, alumina or a mixture thereof, a heating mechanism is arranged on the outside of the evaporator 1, and the heating method adopts one of resistance heating, radiation heating and induction heating. The pipeline between the evaporator 1 and the inlet of the burner 3 is provided with a wear-resistant and high-temperature resistant ceramic lining formed of silicon nitride, zirconia, alumina or a mixture thereof, as well as electric heat tracing and heat preservation.

The mixer 2 is connected with the evaporator 1, and is connected with the evaporator 1 and the burner 3 respectively, and the mixer 2 is used to mix the gaseous zirconium tetrachloride with the hydrogen gas passed into it;

The burner 3 is connected with the mixer 2, and the burner 3 is used to ignite the mixed gaseous zirconium tetrachloride and hydrogen gas introduced into it and the oxygen introduced into it, and the combustion reaction generates solid zirconium dioxide, hydrogen chloride , the first mixture is obtained after the reaction; the burner 3 is provided with a gas distributor 4 for feeding materials into the burner 3, as shown in Figures 3 and 4, the gas distributor 4 includes: an inner ring channel located at the center 5. The middle ring channel 6 that is wrapped in the inner ring channel 5 is annular, and the outer ring channel 7 that is wrapped in the middle ring channel 6 is annular, and the inner ring channel 5 is used for introducing the mixture of gaseous zirconium tetrachloride and hydrogen , the middle ring channel 6 is used for introducing oxygen, and the outer ring channel 7 is used for introducing a mixture of gaseous zirconium tetrachloride and hydrogen. The main material of the burner 3 is a high temperature resistant material of 800H steel, and a wear resistant and high temperature resistant ceramic lining formed of silicon nitride, zirconia, alumina or their composite materials is arranged inside, and a gas distributor 4 is installed at the bottom of the combustion reactor. , to form the reaction conditions in which the flammable gas hydrogen wraps the oxidant oxygen to ensure that the oxidant reacts completely during the reaction process.

The first dust collector 8 is connected to the burner 3, and the first dust collector 8 is used to dedust the first mixture passed into it, the solid zirconium dioxide in the first mixture is separated, and the separated first mixture is obtained. 1. Dedusting exhaust gas; preferably, the first dust collector 8 is a bag-type dust collector, and its filter element adopts a metal sintered filter element or a bag-type filter element.

The cooler 9 is connected to the first dust collector 8, and the cooler 9 is used to cool the first dust removal exhaust gas, and cool the gaseous zirconium tetrachloride into solid zirconium tetrachloride to obtain a cooling mixture; preferably, the cooler 9 A tubular heat exchanger is used, and the refrigerant used is circulating water or steam condensate.

The second dust collector 10 is connected with the cooler 9, and the second dust collector 10 is used for dedusting the cooling mixture, the solid zirconium tetrachloride in the cooling mixture is separated, and the separated second dust removal exhaust gas is obtained;

The deaerator 11 is connected to the second precipitator 10, and the deaerator 11 is used to deoxygenate the second dedusting tail gas to obtain the deaerator tail gas, and the deaerator tail gas includes hydrogen chloride and hydrogen. The deaerator 11 uses silica gel and/or molecular sieve as adsorbents, and realizes the removal of oxygen in the second dedusting tail gas by means of temperature swing adsorption or pressure swing adsorption.

The present embodiment provides a method for preparing zirconium dioxide using the above device, comprising the following steps:

1) Using the purified solid zirconium tetrachloride as the raw material, the solid zirconium tetrachloride is heated and sublimated into gaseous zirconium tetrachloride in the evaporator 1, and the heating temperature in the evaporator 1 is 480°C.

2) after mixing gaseous zirconium tetrachloride and excess hydrogen in mixer 2, enter into combustion reactor through gas distributor 4, and mix with oxygen at the outlet of gas distributor 4, the moles of hydrogen: oxygen The number of moles of zirconium tetrachloride = 2.5:1:1.15, ignition, the reaction generates zirconium dioxide powder, hydrogen chloride gas, the first mixture is obtained after the reaction, after the ignition reaction, the reaction exotherm makes the burner 3 inside The temperature is maintained at 500 ~ 1000 ℃. The temperature in the burner 3 is controlled to be 500 to 1000° C. by adjusting the intake air amount of oxygen in the combustion reactor. During the reaction, the zirconium tetrachloride is slightly excessive, the hydrogen is excessive, and the oxygen reaction is complete. The first mixture comprises: zirconium dioxide content 15-20mol% (solid), hydrogen chloride content 65-75mol%, zirconium tetrachloride content 1-5mol%, hydrogen content 5-10mol%, oxygen content less than 0.1mol%, water vapor The content is less than 0.1 mol%.

3) The zirconium dioxide powder in the first mixture is passed into the first dust collector 8 under the action of air flow for dust removal, and the boiling point of zirconium tetrachloride<the temperature in the first dust collector 8<the temperature of zirconium dioxide. At the boiling point, the solid zirconium dioxide in the first mixture is separated, and the separated first dedusting tail gas is obtained. Specifically, the temperature in the first dust collector 8 in this embodiment is 400-1000°C. The solid zirconium dioxide is discharged through the slag discharge pipeline connected at the bottom of the first dust collector 8 . The first dust removal tail gas includes: the content of zirconium dioxide is less than 0.1mol%, the content of hydrogen chloride is 75-90mol%, the content of zirconium tetrachloride is 2-5mol%, the content of hydrogen is 10-15mol%, the content of oxygen is less than 0.1mol%, and the content of water vapor is less than 0.1 mol%.

4) Passing the first dust removal exhaust gas into the cooler 9 for cooling, and the cooling temperature of the cooler 9 is 180-220°C. The unreacted zirconium tetrachloride vapor in the first dedusting tail gas is cooled to solid zirconium tetrachloride to obtain a cooled mixture. There is no change in the amount of substances during the cooling process, and the cooling mixture includes: the content of zirconium dioxide is less than 0.1mol%, the content of hydrogen chloride is 75-90mol%, the content of zirconium tetrachloride is 2-5mol%, the content of hydrogen is 10-15mol%, and the content of oxygen is less than 0.1mol%, the water vapor content is less than 0.1mol%.

5) The cooling mixture is passed into the second dust collector 10 for dedusting, the solid zirconium tetrachloride in the cooling mixture is separated, and the second dust removal tail gas of separation is obtained; the solid zirconium tetrachloride passes through the bottom of the second dust collector 10 The connected slag discharge line is discharged. The second dedusting tail gas includes: the content of hydrogen chloride is 85-90 mol%, the content of hydrogen is 10-15 mol%, and the content of oxygen is less than 0.1 mol%.

6) Passing the second dust removal tail gas into the deaerator 11 for deoxygenation to obtain the deaerator tail gas, and the deaerator tail gas includes hydrogen chloride and hydrogen. The tail gas of the deaerator includes a mixture of hydrogen chloride and hydrogen with high purity, which can be used as a chlorinating agent in the production process of trichlorosilane. In this embodiment, the chlorine element is fully recycled in the reaction process, which solves the problem of environmental pollution and improves the economic benefit at the same time. The tail gas of the deaerator includes: the content of hydrogen chloride is 85-90 mol%, and the content of hydrogen is 10-15 mol%.

In the preparation method of zirconium dioxide in this embodiment, solid zirconium dioxide is prepared by ignition combustion reaction, which realizes self-sufficiency of heat in the burner 3, thereby saving energy and reducing production cost. The hydrogen chloride produced in the ignition combustion reaction is fully recovered, which solves the problem of environmental pollution and improves economic benefits.

Example 3

This embodiment provides a preparation method of zirconium dioxide, using the preparation device of zirconium dioxide in embodiment 2, the difference between the method in this embodiment and the method in embodiment 2 is:

In step 1), the heating temperature in the evaporator 1 is 420°C;

In step 2), the number of moles of hydrogen: the number of moles of oxygen: the number of moles of zirconium tetrachloride=2.3:1:1.1.

Example 4

This embodiment provides a preparation method of zirconium dioxide, using the preparation device of zirconium dioxide in embodiment 2, the difference between the method in this embodiment and the method in embodiment 2 is:

In step 1), the heating temperature in the evaporator 1 is 530°C;

In step 2), the number of moles of hydrogen: the number of moles of oxygen: the number of moles of zirconium tetrachloride=2.2:1:1.2.

Example 5

As shown in Figure 2, the present embodiment also provides a preparation device for zirconium dioxide, comprising:

Evaporator 1, for heating and subliming solid zirconium tetrachloride into gaseous zirconium tetrachloride;

The mixer 2 is connected with the evaporator 1, and is connected with the evaporator 1 and the burner 3 respectively, and the mixer 2 is used to mix the gaseous zirconium tetrachloride with the hydrogen gas passed into it;

The burner 3 is connected with the mixer 2, and the burner 3 is used to ignite the mixed gaseous zirconium tetrachloride and hydrogen gas introduced into it and the air introduced into it, and the combustion reaction generates solid zirconium dioxide, hydrogen chloride , the first mixture is obtained after the reaction; the burner 3 is provided with a gas distributor 4 for feeding materials into the burner 3, as shown in Figures 3 and 4, the gas distributor 4 includes: an inner ring channel located at the center 5. The middle ring channel 6 that is wrapped in the inner ring channel 5 is annular, and the outer ring channel 7 that is wrapped in the middle ring channel 6 is annular, and the inner ring channel 5 is used for introducing the mixture of gaseous zirconium tetrachloride and hydrogen , the middle ring channel 6 is used for introducing oxygen or air, and the outer ring channel 7 is used for introducing a mixture of gaseous zirconium tetrachloride and hydrogen.

The first dust collector 8 is connected to the burner 3, and the first dust collector 8 is used to dedust the first mixture passed into it, the solid zirconium dioxide in the first mixture is separated, and the separated first mixture is obtained. 1. Dust removal of exhaust gas;

The absorption tower 12 is connected with the first dust collector 8, and the absorption tower 12 is used for adsorbing hydrogen chloride to the first dust removal tail gas, and the tower still liquid of the absorption tower 12 is obtained in the tower still of the absorption tower 12, and the absorption tower 12 is absorbed at the top of the absorption tower 12. The tower tail gas is emptied from the absorption tower tail gas; the absorption tower 12 includes: a tower bottom acid liquid circulation pump 13, a tower top reflux liquid sprayer 14, and the tower bottom acid liquid circulation pump 13 is used to pump the tower still liquid pump of the absorption tower 12 It enters into the analysis tower 15 for analysis, and the tower top reflux liquid sprayer 14 is used to spray the liquid at the top of the absorption tower 12 .

The analysis tower 15 is connected to the absorption tower 12, and the analysis tower 15 is used to analyze the hydrogen chloride in the tower kettle liquid of the absorption tower 12, and the analysis tower tail gas is obtained at the top of the analysis tower 15, and the analysis tower tail gas includes hydrogen chloride. It is connected with the tower top of the absorption tower 12, and the tower still liquid of the analytical tower 15 is passed into the tower top of the absorption tower 12 as the eluent of the absorption tower 12; the tower still of the absorption tower 12 is connected with the tower top of the absorption tower 12, The tower bottom acid liquid circulation pump 13 is also used to pump the tower bottom liquid of the absorption tower 12 to the tower top of the absorption tower 12 as the eluent of the absorption tower 12 . A heater 16 is provided at the bottom of the desorption tower 15 for heating.

The present embodiment provides a method for preparing zirconium dioxide using the above device, comprising the following steps:

1) Using the purified solid zirconium tetrachloride as the raw material, the solid zirconium tetrachloride is heated and sublimated into gaseous zirconium tetrachloride in the evaporator 1, and the heating temperature in the evaporator 1 is 400°C.

2) after mixing gaseous zirconium tetrachloride and excess hydrogen in mixer 2, enter into combustion reactor through gas distributor 4, mix evenly with oxygen at the outlet of gas distributor 4, the number of moles of hydrogen: air The number of moles of oxygen in the medium: the number of moles of zirconium tetrachloride = 2.1:1.3:1, ignition, the reaction generates solid zirconium dioxide and hydrogen chloride, the first mixture is obtained after the reaction, after the ignition reaction, the reaction exotherm makes the burner 3 The temperature is maintained at 500 ~ 1000 ℃. During the reaction, hydrogen and air are excessive, and the reaction of zirconium tetrachloride is complete. The first mixture includes: hydrogen chloride content 35-45mol%, nitrogen content 45-55mol%, zirconium dioxide content 5-15mol% (solid), oxygen content 0-5mol%, water vapor content 0-1mol%, hydrogen content less than 0.1 mol%.

3) Passing the first mixture into the first dust remover 8 for dedusting, the solid zirconium dioxide in the first mixture is separated, and the separated first dedusting tail gas is obtained. The first dedusting tail gas includes: hydrogen chloride content of 40-45 mol%, nitrogen content of 50-55 mol%, oxygen content of 1-5 mol%, water vapor content of 0-1 mol%, and hydrogen content of less than 0.1 mol%.

4) the first dedusting tail gas is passed into the absorption tower 12 to absorb hydrogen chloride, the tower still liquid of the absorption tower 12 is obtained at the tower still of the absorption tower 12, the absorption tower tail gas is obtained at the tower top of the absorption tower 12, and the absorption tower tail gas is vented . The absorption tower 12 uses dilute hydrochloric acid as the absorbent, the first dust removal tail gas enters the absorption tower 12 from the bottom of the absorption tower 12, and is carried out with the acid liquid sprayed down from the top of the absorption tower 12 during the upward movement in the absorption tower 12. Gas-liquid contact, the hydrogen chloride in the first dust removal tail gas is absorbed, the absorption tower tail gas obtained at the top of the absorption tower 12 includes nitrogen and oxygen, and can be directly vented, and the tower still liquid of the absorption tower 12 is high-concentration hydrochloric acid. The tail gas of the absorption tower includes: nitrogen content of 90-98 mol%, oxygen content of 2-5 mol%, moisture content of 0-1 mol%, and hydrogen content of less than 0.1 mol%.

5) Pass the tower still liquid of the absorption tower 12 into the desorption tower 15 to decompose hydrogen chloride, and obtain the desorption tower tail gas at the top of the desorption tower 15, and the desorption tower tail gas includes hydrogen chloride. A heater 16 is provided at the bottom of the desorption tower 15, and the heater 16 is heated so that the temperature at the bottom of the desorption tower 15 is 70-85° C. The hydrogen chloride gas in the acid solution in the desorption tower 15 is transferred from the liquid phase to the gas phase, and the decomposed hydrogen chloride The gas is discharged from the top of the analytical tower 15, and the tail gas of the analytical tower is discharged from the top of the analytical tower 15, which can be used as a chlorinating agent in the trichlorosilane synthesis process. In this embodiment, the chlorine element is fully recycled in the reaction process, which solves the problem of environmental pollution and improves the economic benefit at the same time. The tail gas of the desorption tower includes: 99vol% hydrogen chloride, 1vol% water.

6) Passing the tower bottom liquid of the analysis tower 15 and/or the tower bottom liquid of the absorption tower 12 into the tower top of the absorption tower 12 as the eluent of the absorption tower 12. The low-concentration tower bottom liquid of the analysis tower 15 obtained after the analysis by the analysis tower 15 is passed to the top of the absorption tower 12 .

In the preparation method of zirconium dioxide in this embodiment, solid zirconium dioxide is prepared by ignition combustion reaction, which realizes self-sufficiency of heat in the burner 3, thereby saving energy and reducing production cost. The hydrogen chloride produced in the ignition combustion reaction is fully recovered, which solves the problem of environmental pollution and improves economic benefits.

Example 6

This embodiment provides a preparation method of zirconium dioxide, using the preparation device of zirconium dioxide in embodiment 5, the difference between the method in this embodiment and the method in embodiment 5 is:

In step 1), the heating temperature in the evaporator 1 is 500°C;

In step 2), the number of moles of hydrogen: the number of moles of oxygen: the number of moles of zirconium tetrachloride=2.15:1.1:1.

Example 7

This embodiment provides a preparation method of zirconium dioxide, using the preparation device of zirconium dioxide in embodiment 5, the difference between the method in this embodiment and the method in embodiment 5 is:

In step 1), the heating temperature in the evaporator 1 is 550°C;

In step 2), the number of moles of hydrogen: the number of moles of oxygen: the number of moles of zirconium tetrachloride=2.2:1.5:1.

It can be understood that the above embodiments are only exemplary embodiments adopted to illustrate the principle of the present invention, but the present invention is not limited thereto. For those skilled in the art, without departing from the spirit and essence of the present invention, various modifications and improvements can be made, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims (7)

1. a preparation method of zirconium dioxide, is characterized in that, comprises the following steps: 1) heating and subliming solid zirconium tetrachloride into gaseous zirconium tetrachloride in an evaporator; 2) Ignite gaseous zirconium tetrachloride with hydrogen, oxygen or air in the burner, the number of moles of hydrogen: the number of moles of oxygen: the number of moles of zirconium tetrachloride=(2.2～2.5):1:(1.1～ 1.2), or, the number of moles of hydrogen: the number of moles of oxygen in the air: the number of moles of zirconium tetrachloride=(2.1～2.2): (1.1～1.5): 1, the combustion reaction generates solid zirconium dioxide, hydrogen chloride, and the reaction After obtaining the first mixture, solid zirconium dioxide is prepared through ignition and combustion reaction, and the self-sufficiency of heat in the burner is realized; 3) Passing the first mixture into the first dust collector for dust removal, the solid zirconium dioxide in the first mixture is separated, and the separated first dust removal tail gas is obtained. 2 . The preparation method of zirconium dioxide according to claim 1 , wherein the temperature in the burner in the step 2) is 500-1000° C. 3 . 3. the preparation method of zirconium dioxide according to claim 1, is characterized in that, the boiling point of zirconium tetrachloride<temperature in the first dust collector<the boiling point of zirconium dioxide. 4. the preparation method of zirconium dioxide according to claim 1 or 3, is characterized in that, after described step 3) also comprises the following steps: 4) passing the first dedusting tail gas into the cooler for cooling, and cooling the gaseous zirconium tetrachloride in the first dedusting tail gas to solid zirconium tetrachloride to obtain a cooling mixture; 5) the cooling mixture is passed into the second dust collector for dedusting, the solid zirconium tetrachloride in the cooling mixture is separated, and the second dedusting tail gas that is separated is obtained; 6) Passing the second dedusting tail gas into the deaerator for deoxygenation to obtain the deaerator tail gas, and the deaerator tail gas includes hydrogen chloride and hydrogen. 5 . The method for preparing zirconium dioxide according to claim 4 , wherein, in the step 4), the temperature for cooling through the cooler is 150-220° C. 6 . 6. the preparation method of zirconium dioxide according to claim 1, is characterized in that, after described step 3) also comprises the following steps: 4) pass the first dust removal tail gas into the absorption tower to absorb hydrogen chloride, obtain the tower still liquid of the absorption tower at the tower still of the absorption tower, obtain the absorption tower tail gas at the tower top of the absorption tower, and vent the absorption tower tail gas; 5) Passing the tower bottom liquid of the absorption tower into the desorption tower to decompose hydrogen chloride, and obtains the desorption tower tail gas at the top of the desorption tower, and the desorption tower tail gas includes hydrogen chloride. 7. the preparation method of zirconium dioxide according to claim 6, is characterized in that, after described step 5) also comprises the following steps: 6) Passing the tower still liquid of the desorption tower and/or the tower still liquid of the absorption tower into the tower top of the absorption tower as the eluent of the absorption tower.

Images