Cerium zirconium solid solution production apparatus and method

Abstract

The application discloses a cerium-zirconium solid solution production device and method, which comprises a pyrolysis furnace, a feeding unit, a gas-solid separation unit and a decompression device. The pyrolysis furnace is provided with a pyrolysis furnace body having a containing cavity, a precursor outlet symmetrically arranged at the top of the containing cavity, a cerium-zirconium solid solution inlet symmetrically arranged at the lower part of the side wall of the containing cavity, and a cerium-zirconium solid solution collecting port arranged at the bottom of the containing cavity. The feeding unit comprises a nozzle arranged below and close to the top of the pyrolysis furnace body. The gas-solid separation unit comprises a separator, an exhaust pipe and an outlet pipe. The top of the separator is provided with the exhaust pipe. The exhaust pipe is connected with the outlet pipe. The upper part of the separator is connected with the precursor outlet through a pipeline. The bottom of the separator is connected with the cerium-zirconium solid solution inlet through a pipeline. The decompression device is connected with the outlet pipe to form a negative pressure in the device. The device can obtain a low-chlorine cerium-zirconium solid solution with high purity.

Description

TECHNICAL FIELD

[0001] The present application relates to a cerium-zirconium solid solution production device and method. BACKGROUND

[0002] As an oxygen storage material, rare earth cerium oxide (CeO X ) is widely used in the field of automobile exhaust purification. However, ceria is easy to sinter at 1000℃, which reduces the specific surface area and leads to a serious decline in oxygen absorption and release capacity, which seriously limits the application of ceria. In the prior art, ceria is often doped with zirconium oxide (ZrO2) to form Ce x Zr 1-X O2 solid solution to improve the structural stability, temperature resistance and oxygen absorption and release capacity of ceria.

[0003] At present, the commonly used preparation method of Ce x Zr 1-X O2 solid solution includes co-precipitation method, sol-gel method, high-temperature calcination method and high-energy ball milling method. The co-precipitation method has a long production process, many operation steps, consumes many raw materials and has complex influencing factors. The sol-gel method needs a long preparation process, and many gases and organic matters are emitted during the drying process. The final product is prone to shrinkage, and the production cost is high. The catalyst prepared by the high-temperature calcination method has good high-temperature resistance, but the particles are seriously aggregated, and the high-temperature energy consumption is huge. The particles prepared by the high-energy ball milling method have good dispersibility and uniform particle size distribution, but the particle crystal type is not fully developed due to the lack of high-temperature calcination, which seriously affects the service time of the catalyst. SUMMARY

[0004] Therefore, one object of the present application is to provide a cerium-zirconium solid solution production device. The purity of the cerium-zirconium solid solution can be improved and the chlorine content can be reduced by using the device. Another object of the present application is to provide a method for producing cerium-zirconium solid solution, which can improve the production efficiency and reduce the production consumption.

[0005] The present application achieves the above-mentioned objects by adopting the following technical solutions.

[0006] In one aspect, the present application provides a cerium-zirconium solid solution production device, which comprises a pyrolysis furnace, a feeding unit, a gas-solid separation unit and a pressure reduction device.

[0007] The pyrolysis furnace is configured to form a cerium-zirconium solid solution, and comprises a pyrolysis furnace body; the pyrolysis furnace body has a containing cavity, the top of which is symmetrically provided with a precursor outlet; the lower part of the side wall of the pyrolysis furnace body is symmetrically provided with a cerium-zirconium solid solution inlet; and the bottom of the pyrolysis furnace body is provided with a cerium-zirconium solid solution collection port.

[0008] The feeding unit comprises a nozzle, which is arranged below and close to the top of the pyrolysis furnace body and is configured to form a spray of the aqueous solution containing chloride for producing cerium-zirconium solid solution;

[0009] The gas-solid separation unit comprises a separator, an exhaust pipe and an outlet pipe. The top of the separator is provided with the exhaust pipe. The exhaust pipe is connected with the outlet pipe. The upper part of the separator is connected with the precursor outlet through a pipeline. The bottom of the separator is connected with the cerium-zirconium solid solution inlet through a pipeline.

[0010] The decompression device is connected with the outlet pipe to form a negative pressure in the device.

[0011] In the present application, the pyrolysis furnace comprises a pyrolysis furnace body. The pyrolysis furnace body has a containing cavity. The longitudinal section of the top of the pyrolysis furnace body can have an isosceles trapezoidal structure, and the top is symmetrically provided with a precursor outlet on the waist. The lower part of the side wall of the pyrolysis furnace body is symmetrically provided with a cerium-zirconium solid solution inlet, and the bottom is provided with a cerium-zirconium solid solution collection port. In this way, the product can be conveniently collected, and the loss of the product is small, and the yield is higher.

[0012] In the present application, the nozzle of the feeding unit is arranged below and close to the top of the pyrolysis furnace body. Spraying from top to bottom can reduce the contact time and thus reduce the loss of the material.

[0013] In the present application, the gas-solid separation unit is used for gas-solid separation of the gas-solid two-phase fluid after thermal decomposition. The gas-solid separation unit can be a cyclone separator. The gas-solid separation unit can be symmetrically arranged on both sides of the pyrolysis furnace, so that a symmetric cyclone is formed in the device, the material separation is stable, and deviation does not occur. The gas-solid separation effect is good. The decompression device forms a negative pressure in the whole device, so that the speed of the precursor carried by hot air entering the gas-solid separation unit is stabilized at 1-10 m / s. After the pyrolysis product enters the separation device, it reacts with HCl at a faster speed, so as to inhibit the content of product chloride and reduce the chlorine content in the cerium-zirconium solid solution.

[0014] According to the device of the present application, preferably, the gas-solid separation unit is arranged as at least two. In some embodiments, two gas-solid separation units can be symmetrically arranged on both sides of the pyrolysis furnace. Correspondingly, the top of the pyrolysis furnace body is symmetrically provided with two precursor outlets, which are a first outlet and a second outlet. The lower part of the side wall is symmetrically provided with two cerium-zirconium solid solution inlets, which are a first inlet and a second inlet. The upper parts of the two gas-solid separation units are connected with the first outlet and the second outlet through pipelines, respectively. The bottoms of the two gas-solid separation units are connected with the first inlet and the second inlet through pipelines, respectively.

[0015] According to the device of the present application, preferably, the feeding unit further comprises a feeding pipe, a storage tank and an air pump; one end of the feeding pipe is connected with the nozzle, and the other end is connected with the storage tank; one end of the storage tank is connected with the air pump, and the storage tank is used for containing the aqueous solution containing chlorides. One end of the feeding pipe penetrates through the top of the pyrolysis furnace body and extends to 30-100 cm below the top, preferably 50-90 cm, and more preferably 70-80 cm.

[0016] According to the device of the present application, preferably, it further comprises an insulation layer, which is arranged around the sidewall of the pyrolysis furnace body and is made of refractory material.

[0017] According to the device of the present application, preferably, the bottom of the separator is connected with the cerium-zirconium solid solution inlet through a pipe with a bending structure. This is more conducive to the solid solution separated by the gas-solid separation unit to enter the pyrolysis furnace body.

[0018] According to the device of the present application, preferably, a cutout is arranged on the exhaust pipe, and the exhaust pipe is connected with the outlet pipe perpendicularly through the cutout.

[0019] On the other hand, the present application provides a method for producing cerium-zirconium solid solution by using the above device, which comprises the following steps:

[0020] (1) Dissolving cerium chloride and zirconium oxychloride in water to form a solution, and then adding an organic chelating agent to obtain an aqueous solution containing chlorides; wherein the ratio of the number of moles of the organic chelating agent to the total number of moles of cerium and zirconium is 1-4:1; the organic chelating agent is selected from at least one of citric acid, tartaric acid and ethylenediaminetetraacetic acid;

[0021] (2) Heating the pyrolysis furnace to 600-900℃, and spraying the aqueous solution containing chlorides into the pyrolysis furnace through the nozzle with air as the carrier to form a spray, and then forming a precursor through a thermal decomposition reaction;

[0022] (3) passing the precursor through the precursor outlet to the gas-solid separation unit for gas-solid separation, discharging the gas through the exhaust pipe, and passing the cerium-zirconium solid solution into the pyrolysis furnace body through the cerium-zirconium solid solution inlet and discharging it from the cerium-zirconium solid solution collection outlet;

[0023] Among them, the content of chlorine in the cerium-zirconium solid solution is less than 0.1wt%.

[0024] In step (1), cerium chloride and zirconium oxychloride are used as raw materials, and a mixed solution is obtained after adding an organic chelating agent. The ratio of the number of moles of the organic chelating agent to the total number of moles of cerium and zirconium can be 1-4:1, and preferably 1-3:1.

[0025] The organic chelating agent can be selected from at least one of citric acid, tartaric acid, and ethylenediaminetetraacetic acid. Preferably, the organic chelating agent is a mixture of citric acid, tartaric acid, and ethylenediaminetetraacetic acid.

[0026] According to the method of the present application, preferably, the concentration of cerium chloride in the chloride-containing aqueous solution is 100-300 g / L; more preferably, the concentration of cerium chloride is 100-250 g / L; and even more preferably, the concentration of cerium chloride is 150-200 g / L. The concentration of zirconium oxychloride in the chloride-containing aqueous solution can be 6-240 g / L, preferably 90-180 g / L, and more preferably 110-150 g / L. This is conducive to the formation of cerium-zirconium solid solution with low chlorine content.

[0027] In step (2) of the present application, the temperature of thermal decomposition can be 600-900 ℃, preferably 650-850 ℃, and more preferably 700-800 ℃.

[0028] The equation of the above reaction is:

[0029] 2CeCl3+2ZrOCl2+2H2O+2O2=4Ce 0.5 Zr 0.5 O2+4HCl+3Cl2.

[0030] Chloride ions affect the catalytic performance of cerium-zirconium solid solution. Generally, in the catalyst powder, chloride ions exist in the form of adsorption, wrapping, and inclusion. If the current dechlorination technology (such as hydrogen reduction dechlorination, water washing dechlorination, high-temperature calcination dechlorination, and electrodialysis for chloride ions) is used for capture, complicated operation procedures, expensive equipment investment, and certain processing costs are required, and the processing process also affects the physical and chemical properties of the powder material. The present application finds that in the upper section of the pyrolysis furnace, the spraying (droplets) of the chloride-containing aqueous solution simultaneously occurs the pyrolysis reaction of cerium chloride and zirconium oxychloride and the combustion reaction of the organic chelating agent. This can provide a high-concentration carbon dioxide atmosphere around the droplets, achieving the purpose of reducing the partial pressure of HCl and reducing chlorine gas. Therefore, this is conducive to obtaining cerium-zirconium solid solution with high purity and low chlorine content.

[0031] According to the method of the present application, preferably, the particle size of the spray is 10-200 μm, more preferably, the particle size of the spray is 30-150 μm; and even more preferably, the particle size of the spray is 50-140 μm.

[0032] According to the method of the present application, preferably, the speed of the precursor entering the gas-solid separation unit is 1-10 m / s; more preferably, the speed is 4-9 m / s; and even more preferably, the speed is 6-8 m / s.

[0033] The device of the application can improve the purity of cerium-zirconium solid solution to more than 99%, and reduce the content of chlorine to less than or equal to 0.1 wt%. The method of the application can improve production efficiency and reduce production consumption. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 The device for producing cerium-zirconium solid solution of Example 1.

[0035] Figure 2 The structure diagram of the gas-solid separation unit of Example 1.

[0036] Figure 3 The SEM diagram of the cerium-zirconium solid solution prepared in Example 1.

[0037] Figure 4 The energy spectrum diagram of the cerium-zirconium solid solution prepared in Example 1.

[0038] Figure 5 The SEM diagram of the cerium-zirconium solid solution prepared in Example 2.

[0039] Figure 6 The energy spectrum diagram of the cerium-zirconium solid solution prepared in Example 2.

[0040] Figure 7 The SEM diagram of the cerium-zirconium solid solution prepared in Example 3.

[0041] Figure 8 The energy spectrum diagram of the cerium-zirconium solid solution prepared in Example 3.

[0042] Figure 9 The SEM diagram of the cerium-zirconium solid solution prepared in Example 4.

[0043] Figure 10 The energy spectrum diagram of the cerium-zirconium solid solution prepared in Example 4.

[0044] BRIEF DESCRIPTION OF DRAWINGS

[0045] 1-pyrolysis furnace; 11-pyrolysis furnace body; 111-first outlet; 112-second outlet; 113-first inlet; 114-second inlet; 115-cerium-zirconium solid solution collection port; 12-heat preservation layer; 2-feeding unit; 21-nozzle; 22-feeding pipe; 23-liquid storage tank; 24-air pump; 3-gas-solid separation unit; 31-separator; 32-exhaust pipe; 33-outlet pipe. DETAILED DESCRIPTION

[0046] The following describes the test methods used in the examples and comparative examples:

[0047] SEM (scanning electron microscope) and energy spectrum analysis:

[0048] (1) SEM analysis: sigma300 ultra-high resolution hot field emission scanning electron microscope produced by Zeiss Company of Germany was used for analysis.

[0049] (2) Energy spectrum analysis: Oxford X-Max N 20 energy spectrometer was used for analysis.

[0050] The content of cerium, zirconium and chloride ions: all were determined by energy spectrometer.

[0051] Example 1

[0052] Figure 1 is the production device for cerium-zirconium solid solution of the present application. Figure 2 is a structural schematic view of the gas-solid separation unit of the present application.

[0053] As shown in Figure 1 and Figure 2 , the production device for cerium-zirconium solid solution of the present embodiment comprises a pyrolysis furnace 1, a feeding unit 2, a gas-solid separation unit 3 and a pressure reduction device (not shown). In the present embodiment, the gas-solid separation unit 3 is provided in two, which are symmetrically arranged on both sides of the pyrolysis furnace 1. In this way, a symmetric cyclone can be formed in the device, and the material separation is relatively stable and will not deviate, and the gas-solid separation effect is good.

[0054] The pyrolysis furnace 1 comprises a pyrolysis furnace body 11 and an insulation layer 12. The pyrolysis furnace body 11 has a containing cavity. The top of the pyrolysis furnace body 11 is symmetrically provided with precursor outlets, which are a first outlet 111 and a second outlet 112, respectively. The lower part of the side wall of the pyrolysis furnace body 11 is symmetrically provided with cerium-zirconium solid solution inlets, which are a first inlet 113 and a second inlet 114, respectively. The bottom of the pyrolysis furnace body 11 is provided with a cerium-zirconium solid solution collecting port 115. The insulation layer 12 is arranged around the side wall of the pyrolysis furnace body 11, which is made of refractory material.

[0055] The feeding unit 2 comprises a nozzle 21, a feeding pipe 22, a liquid storage tank 23 and an air pressure pump 24. One end of the feeding pipe 22 is connected with the nozzle 21, and the other end is connected with the liquid storage tank 23, and the liquid storage tank 23 is connected with the air pressure pump 24. The liquid storage tank 23 contains a chloride-containing aqueous solution, which is delivered to the nozzle 21 through the feeding pipe 22 to form a spray.

[0056] As shown in Figure 2As shown, the gas-solid separation unit 3 comprises separators 31, exhaust pipes 32 and outlet pipes 33. The top of the separators 31 is provided with the exhaust pipes 32 for discharging the gas after gas-solid separation. The exhaust pipes 32 are provided with cutouts, and the exhaust pipes 32 are connected to the outlet pipes 33 perpendicularly through the cutouts. The upper parts of the two separators 31 are connected to the first outlet 111 and the second outlet 112 respectively through pipes. The precursors formed through the pyrolysis reaction in the pyrolysis furnace enter the gas-solid separation unit 3 from the first outlet 111 and the second outlet 112 of the pyrolysis furnace 1. The bottom parts of the two separators 31 are connected to the first inlet 113 and the second inlet 114 respectively through pipes, which are in a bent structure. The cerium-zirconium solid solution after gas-solid separation enters the pyrolysis furnace 1 through the first inlet 113 and the second inlet 114 and is collected through the cerium-zirconium solid solution collecting port 115.

[0057] In this embodiment, the pressure reducing device is an induced draft fan, which is connected to the outlet pipes 33 of the gas-solid separation unit 2 and used to adjust the air pressure in the device to be negative pressure. Through the air extraction of the induced draft fan, the negative pressure is formed in the whole device, so that the speed of the precursors with hot air as the carrier entering the gas-solid separation unit 2 is stabilized between 1-10 m / s.

[0058] The method for producing cerium-zirconium solid solution by using the above device is described as follows:

[0059] A solution of 200 ml is prepared by dissolving cerium chloride with a concentration of 200 g / L and zirconium oxychloride with a concentration of 160 g / L in deionized water; then an organic chelating agent (citric acid, tartaric acid and ethylenediaminetetraacetic acid) is added to the above solution to obtain a water solution containing chlorides, and the molar ratio of the organic chelating agent to the total moles of cerium and zirconium is 1:1.

[0060] The pyrolysis furnace 1 is heated to 650°C, then the water solution containing chlorides is sprayed into the pyrolysis furnace 1 through the nozzle 21 with compressed air as the carrier to form a spray of 10-80 μm, and then the precursors are formed through the pyrolysis reaction.

[0061] Through the air extraction of the induced draft fan, the negative pressure is formed in the whole device, so that the precursors with hot air as the carrier enter the gas-solid separation unit 3 for gas-solid separation at a speed of 10 m / s, the gas is discharged through the exhaust pipes 32, the cerium-zirconium solid solution enters the pyrolysis furnace body 11 through the first inlet 111 and the second inlet 112, and is discharged through the cerium-zirconium solid solution collecting port 115 for unified collection. The SEM image of the obtained cerium-zirconium solid solution is shown in Figure 3 (spectrum 33), and the energy spectrum thereof is shown in Figure 4 (spectrum 33).

[0062] Example 2

[0063] The device used in this embodiment is the same as that in Embodiment 1.

[0064] The method for producing cerium-zirconium solid solution in this embodiment is as follows:

[0065] Cerium chloride with a concentration of 150 g / L and zirconium oxychloride with a concentration of 120 g / L were dissolved in deionized water to prepare a 400-ml solution; organic chelating agents (citric acid, tartaric acid and ethylenediaminetetraacetic acid) were then added to the above solution to obtain a chloride-containing aqueous solution, and the molar ratio of the organic chelating agents to the total moles of cerium and zirconium was 2:1.

[0066] The spray pyrolysis furnace 1 was heated to 850°C, and then the chloride-containing aqueous solution was sprayed into the spray pyrolysis furnace 1 through the nozzle 21 with compressed air as the carrier to form a spray with a particle size of 50-100 μm, and then the precursor was formed through a thermal decomposition reaction.

[0067] Air was drawn by the induced draft fan to form a negative pressure in the whole device, so that the precursor with hot air as the carrier entered the gas-solid separation unit 3 at a speed of 8 m / s for gas-solid separation, the gas was discharged through the exhaust pipe 32, and the cerium-zirconium solid solution entered the spray pyrolysis furnace body 11 through the first inlet 111 and the second inlet 112, and was discharged from the cerium-zirconium solid solution collection port 115 for unified collection. The SEM image of the obtained cerium-zirconium solid solution is shown in Figure 5 (spectrum 40), and its energy spectrum is shown in Figure 6 (spectrum 40).

[0068] Example 3

[0069] The device used in this embodiment is the same as that in Embodiment 1.

[0070] The method for producing cerium-zirconium solid solution in this embodiment is as follows:

[0071] Cerium chloride with a concentration of 200 g / L and zirconium oxychloride with a concentration of 150 g / L were dissolved in deionized water to prepare a 300-ml solution; organic chelating agents (citric acid, tartaric acid and ethylenediaminetetraacetic acid) were then added to obtain a chloride-containing aqueous solution, and the molar ratio of the organic chelating agents to the total moles of cerium and zirconium was 3:1.

[0072] The spray pyrolysis furnace 1 was heated to 700°C, and then the chloride-containing aqueous solution was sprayed into the spray pyrolysis furnace 1 through the nozzle 21 with compressed air as the carrier to form a spray with a particle size of 30-130 μm, and then the precursor was formed through a thermal decomposition reaction.

[0073] Air was drawn by the induced draft fan to form a negative pressure in the whole device, so that the precursor with hot air as the carrier entered the gas-solid separation unit 3 at a speed of 6 m / s for gas-solid separation, the gas was discharged through the exhaust pipe 32, and the cerium-zirconium solid solution entered the spray pyrolysis furnace body 11 through the first inlet 111 and the second inlet 112, and was discharged from the cerium-zirconium solid solution collection port 115 for unified collection. The SEM image of the obtained cerium-zirconium solid solution is shown inFigure 7 (figure 18), the energy spectrum of which is shown in Figure 8 (figure 18).

[0074] Example 4

[0075] The device used in this embodiment is the same as that of embodiment 1.

[0076] The method for producing cerium-zirconium solid solution in this embodiment is as follows:

[0077] A solution of 200 ml is prepared by dissolving cerium chloride with a concentration of 100 g / L and zirconium oxychloride with a concentration of 70 g / L in deionized water; an organic chelating agent (citric acid, tartaric acid and ethylenediaminetetraacetic acid) is then added to obtain a water solution containing chlorides, and the molar ratio of the organic chelating agent to the total moles of cerium and zirconium is 4:1.

[0078] The spray pyrolysis furnace 1 is heated to 800℃, and then the water solution containing chlorides is sprayed into the pyrolysis furnace 1 through the nozzle 21 by compressed air carrier to form a spray of 80-140 μm, and then the precursor is formed through thermal decomposition reaction.

[0079] A negative pressure is formed in the whole device by air extraction of the induced draft fan, so that the precursor with hot air as carrier enters the gas-solid separation unit 3 at a speed of 9 m / s for gas-solid separation, the gas is discharged through the exhaust pipe 32, and the cerium-zirconium solid solution enters the pyrolysis furnace body 11 through the first inlet 111 and the second inlet 112, and is discharged from the cerium-zirconium solid solution collection port 115 for unified collection. The SEM image of the obtained cerium-zirconium solid solution is shown in Figure 9 (figure 15), the energy spectrum of which is shown in Figure 10 (figure 15).

[0080] The purity of the cerium-zirconium solid solution prepared in embodiments 1-4 is greater than 99%, and the chlorine content in the cerium-zirconium solid solution is less than 0.1%.

[0081] Comparative Example 1

[0082] The difference from embodiment 1 is that the nozzle is arranged at the bottom of the spray pyrolysis furnace, and the gas-solid separation unit is arranged in two stages in series without forming a negative pressure environment.

[0083] The above embodiments have poor effect of reducing chlorine content, and the spray contact time is relatively long in the downward spray, which will cause certain material loss. The gas-solid separation unit is connected in two stages in series, and the material separated will deviate and be unstable, which reduces the effect of gas-solid separation, and multiple collection tanks are needed for batch collection, which will also affect the yield.

[0084] The present application is not limited to the above-described embodiments, and any modification, improvement, replacement that can be conceived by those skilled in the art without departing from the essential content of the present application falls within the scope of the present application.

Claims

1. A cerium-zirconium solid solution production apparatus, characterized in that, The pyrolysis furnace, the feeding unit, the gas-solid separation unit and the pressure reduction device are included. The pyrolysis furnace is arranged to form a cerium-zirconium solid solution, and includes a pyrolysis furnace body having a containing cavity, a front body outlet symmetrically arranged at the top of the containing cavity, a cerium-zirconium solid solution inlet symmetrically arranged at the lower part of the side wall of the pyrolysis furnace body, and a cerium-zirconium solid solution collecting port arranged at the bottom of the pyrolysis furnace body. The feeding unit includes a nozzle arranged below and close to the top of the pyrolysis furnace body, and the nozzle is arranged to form a spray of the chloride-containing aqueous solution used for producing the cerium-zirconium solid solution. The gas-solid separation unit includes a separator, an exhaust pipe and an outlet pipe, the separator is provided with the exhaust pipe at the top, the exhaust pipe is connected with the outlet pipe, the upper part of the separator is connected with the front body outlet through a pipeline, and the bottom of the separator is connected with the cerium-zirconium solid solution inlet through a pipeline. The pressure reduction device is connected with the outlet pipe to form a negative pressure inside the separator.

2. The apparatus of claim 1, wherein, The gas-solid separation unit is arranged in at least two.

3. The apparatus of claim 2, wherein, The feeding unit further includes a feeding pipe, a liquid storage tank and an air pressure pump, one end of the feeding pipe is connected with the nozzle, the other end of the feeding pipe is connected with the liquid storage tank, one end of the liquid storage tank is connected with the air pressure pump, and the liquid storage tank is used for containing the chloride-containing aqueous solution.

4. The apparatus of claim 1, wherein, A heat insulation layer is further included, and the heat insulation layer is arranged around the side wall of the pyrolysis furnace body and is made of refractory material.

5. The apparatus of claim 4, wherein, The bottom of the separator is connected with the cerium-zirconium solid solution inlet through a pipeline in a bent structure.

6. The apparatus of claim 1, wherein, A cutout is arranged on the exhaust pipe, and the exhaust pipe is connected with the outlet pipe perpendicularly through the cutout.

7. A method for producing ceria-zirconia solid solution using the apparatus according to any one of claims 1 to 6, characterized by, The method includes the following steps: (1) dissolving cerium chloride and zirconium oxychloride in water to prepare a solution, and then adding an organic chelating agent to obtain a chloride-containing aqueous solution, wherein the ratio of the number of moles of the organic chelating agent to the total number of moles of cerium and zirconium is 1-4:1, and the organic chelating agent is at least one selected from citric acid, tartaric acid and ethylenediaminetetraacetic acid; (2) heating the pyrolysis furnace to 600-900 ℃, spraying the chloride-containing aqueous solution into the pyrolysis furnace through the nozzle with air as the carrier to form a spray, and forming a precursor through a thermal decomposition reaction; (3) separating the precursor through the gas-solid separation unit, discharging the gas through the exhaust pipe, and discharging the cerium-zirconium solid solution into the pyrolysis furnace body through the cerium-zirconium solid solution inlet and then discharging the cerium-zirconium solid solution from the cerium-zirconium solid solution collecting port; The content of chlorine in the cerium-zirconium solid solution is less than 0.1 wt%.

8. The method of claim 7, wherein, In the chloride-containing aqueous solution, the concentration of cerium chloride is 100-300 g / L, and the concentration of zirconium oxychloride is 6-240 g / L.

9. The method of claim 7, wherein, In step (2), the particle size of the spray is 10-200 μm.

10. The method of claim 7, wherein, In step (3), the speed of the precursor entering the gas-solid separation unit is 1-10 m / s.

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