Copper-based catalyst and application thereof in catalytic preparation of chlorine from hydrogen chloride and oxygen

Abstract

The invention relates to a method for preparing chlorine by using hydrogen chloride and oxygen, which belongs to the technical field of treatment and utilization of hydrogen chloride, and comprises the following steps: step 1, mixing hydrogen chloride gas and oxygen, inputting the mixture into a reactor filled with a copper-based catalyst at the temperature of 260-400 DEG C and the pressure of 0-1.0 MpaG, and carrying out catalytic oxidation on the hydrogen chloride gas to form chlorine and water vapor; and 2, separating water vapor, incompletely reacted hydrogen chloride gas and oxygen, and rectifying to obtain liquid chlorine, namely cooling in a quench tower and absorbing hydrogen chloride, absorbing water vapor in a drying tower, and separating oxygen in a chlorine rectifying tower to obtain liquid chlorine. After the copper-based catalyst is used, the reaction air speed is high, the space time yield (STY) is larger than 5.6 gcl2 / gcat.h, the hydrogen chloride conversion rate is larger than or equal to 93 wt%, the hydrogen chloride conversion rate is high, the catalyst dosage is small, the cost of the copper-based catalyst is lower, and the whole technological process is short, low in energy consumption and low in operation cost.

Description

Technical Field

[0001] The invention belongs to the technical field of treatment and utilization of by-product hydrogen chloride in the chlorine industry, and in particular relates to a copper-based catalyst and application thereof in catalytic preparation of chlorine by hydrogen chloride and oxygen. Background Art

[0002] Chlorine is an important chemical raw material. my country's annual chlorine consumption exceeds 20 million tons, accounting for more than 1 / 3 of the world's chlorine consumption, and almost all of this chlorine is supplied by chlor-alkali plants. However, chlor-alkali production consumes up to 2760 kWh of electricity per ton of chlorine, and the electricity consumption of the entire chlor-alkali industry accounts for about 5% of my country's electricity consumption. In addition, when the market demand for chlorine and alkali fluctuates, it will lead to the problem of unbalanced development of the chlor-alkali industry.

[0003] On the other hand, the production of chlorine-related products, such as MDI, TDI, and methane chloride, generally has the problem of low chlorine atom utilization. For every mole of chlorine consumed, one mole of by-product hydrogen chloride is produced. At present, most of the by-product hydrogen chloride is absorbed by water and made into hydrochloric acid. According to incomplete statistics, the total amount of industrial by-product hydrogen chloride in my country is close to 4 million tons / year. With the large-scale expansion of chlorine-related products such as MDI, TDI, and methane chloride and the development of the chlor-alkali industry, it is estimated that the total amount of by-product hydrogen chloride will reach 5 million tons / year in the next five years. Hydrochloric acid has low added value, high transportation and storage costs, and is difficult to sell. The discharge destination of hydrochloric acid has become a bottleneck restricting the further development of chlorine-consuming industries.

[0004] If the large amount of hydrogen chloride produced as a byproduct in industry and difficult to handle can be directly converted into chlorine for utilization, the closed-loop circulation of chlorine and zero emission of the reaction process can be achieved, which can not only solve the problem of excess hydrogen chloride in chlorine-consuming industries, but also meet the growing demand for chlorine in industry to a certain extent, promote the healthy development of emerging industries and the optimization and upgrading of the chlor-alkali industry, and meet the overall requirements of sustainable development of the industry. At present, the methods for preparing chlorine from hydrogen chloride can be mainly divided into three categories: electrolysis, direct oxidation and catalytic oxidation.

[0005] The electrolysis method converts hydrogen chloride into chlorine gas by electrolysis, which can be divided into dry method and wet method. However, the electrolysis method has disadvantages such as high operating cost and large investment. At the same time, the electrolysis process is very sensitive to impurities in the hydrochloric acid raw material, and the by-product hydrogen chloride gas or hydrochloric acid contains other impurities to a greater or lesser extent. Therefore, the hydrochloric acid electrolysis chlorine production technology cannot be widely promoted and applied.

[0006] Direct oxidation is a method of preparing chlorine by directly oxidizing hydrogen chloride with inorganic oxidants such as MnO2, H2O2, and NO2. Typical examples include the Weldson process, the Kel-Chlor process, and the DEGUSSA process. The direct oxidation method is difficult to industrialize due to its complex reaction equipment, difficulty in product separation, high energy consumption, and difficulty in waste liquid treatment.

[0007] The catalytic oxidation method is a method of oxidizing hydrogen chloride into chlorine and H2O using oxygen under catalytic conditions. Representative methods include the Deacon process, the Shell process, and the technology of Sumitomo of Japan. Sumitomo Chemical Co., Ltd. of Japan has developed a rutile TiO2-loaded ruthenium oxide catalyst and has applied for a large number of patents in the catalyst field, forming a technical blockade. The company has also developed a complete set of equipment using this catalyst, but the process of the complete set of equipment is complicated and the catalyst is expensive. Summary of the invention

[0008] The technical problem to be solved by the present invention is to propose a copper-based catalyst and its application in the catalytic preparation of chlorine from hydrogen chloride and oxygen, so as to solve the problems of complex equipment, difficult product separation, high energy consumption, expensive catalysts and complicated complete set process in the existing industry of preparing chlorine from hydrogen chloride.

[0009] In order to solve the above technical problems, the technical solution provided by the present invention is: The present invention relates to a copper-based catalyst, which is loaded on a catalyst carrier, and the catalyst carrier is α-Al2O3 microcrystals. The preparation process comprises: loading a solution containing a copper compound, a nickel compound, a molybdenum compound, a lanthanum compound, a bismuth compound and a vanadium compound on the catalyst carrier, heating and decomposing the solution to obtain copper atoms, nickel atoms, molybdenum atoms, lanthanum atoms, bismuth atoms and vanadium atoms, and loading the solution on the catalyst carrier to obtain Cu 10 Ni4Mo1La3Bi3V1.

[0010] Preferably, the copper compound is copper chloride or copper nitrate, the nickel-containing compound is nickel nitrate hexahydrate or nickel nitrate, the molybdenum-containing compound is ammonium molybdate, the lanthanum-containing compound is lanthanum nitrate or lanthanum chloride, the bismuth-containing compound is bismuth nitrate or bismuth vanadate, and the vanadium-containing compound is one of bismuth vanadate, indium vanadate, silver vanadate, iron vanadate, and vanadium dichloride.

[0011] Preferably, the copper compound is copper chloride, the nickel-containing compound is nickel nitrate hexahydrate, the molybdenum-containing compound is ammonium molybdate, the lanthanum-containing compound is lanthanum chloride, the bismuth-containing compound is bismuth nitrate, and the vanadium-containing compound is vanadium dichloride; the preparation process of the copper-based catalyst includes: (1) Add copper chloride, nickel nitrate hexahydrate, ammonium molybdate, lanthanum chloride, bismuth nitrate and vanadium dichloride into pure water at a molar ratio of 10:4:1:3:3:1 and stir to fully dissolve them, then immerse α-Al2O3 microcrystals for 12-24 hours; (2) filtering the impregnated α-Al2O3 microcrystals and drying them at 80-100°C for 12-24 hours; (3) Calcine the α-Al2O3 microcrystals at 480-600°C for 6-8 hours to obtain a copper-based catalyst, and extrude the shaped particles into particles with an average diameter of 0.1-0.5 mm.

[0012] The invention also relates to the application of copper-based catalysts in catalytically preparing chlorine from hydrogen chloride and oxygen.

[0013] Preferably, it comprises the following steps: Step 1. After the hydrogen chloride gas and oxygen are mixed, they are input into a reactor equipped with a copper-based catalyst. The reactor temperature is 260-400°C and the pressure is 0-1.0MpaG to catalytically oxidize the hydrogen chloride gas to form chlorine and water vapor; Step 2: Separate water vapor, incompletely reacted hydrogen chloride gas and oxygen, and distill to obtain liquid chlorine.

[0014] Preferably, the step 2 specifically includes: Step 2.1. The high-temperature mixed gas formed after catalytic oxidation is passed into a quenching tower, which rapidly cools the high-temperature mixed gas and absorbs unreacted hydrogen chloride gas; Step 2.2. The mixed gas after the removal of hydrogen chloride gas enters a drying tower for drying, and the drying tower absorbs water vapor through concentrated sulfuric acid in countercurrent contact with the mixed gas after the removal of hydrogen chloride gas; Step 2.3. The dried mixed gas is sequentially introduced into a compressor and a condenser for compression and condensation; Step 2.4. The compressed and condensed mixed gas is passed into a chlorine distillation tower to separate oxygen and distill to obtain liquid chlorine.

[0015] Preferably, in step 2.1, the temperature of the bottom of the quenching tower is controlled at 20-60° C. by a circulating cooler, and distilled water is introduced into the top of the quenching tower. The distilled water absorbs unreacted hydrogen chloride gas to form hydrochloric acid which is recovered from the bottom of the bottom of the quenching tower.

[0016] Preferably, in step 1, the molar ratio of hydrogen chloride gas to oxygen is 1:0.25-1:1, hydrogen chloride gas and oxygen are introduced into a preheater to be mixed and preheated, and then introduced into a reactor equipped with a copper-based catalyst after preheating, and the temperature of the preheated mixed gas is 200-350°C; the hydrogen chloride gas releases heat when catalytically oxidized in the reactor, and the heat is transferred out of the reactor through the medium in the heat circulation device and enters the waste heat boiler, and distilled water is introduced into the waste heat boiler, and the distilled water is heated to form steam and returns to the preheater for preheating hydrogen chloride gas and oxygen, and the medium returns to the reactor to reabsorb heat; the heat circulation device is a molten salt circulation device or a pressurized heat transfer oil circulation device; The temperature in the reactor of step 1 is 335-350° C. and the pressure is 0.2-0.6 MpaG.

[0017] Preferably, in step 2.3, the compressor compresses the dried mixed gas to 1-1.5 MPaG, and the condenser cools it to -20--60°C; in step 2.4, the bottom temperature of the chlorine distillation tower is controlled at 60-90°C, and the top temperature is controlled at -20--60°C.

[0018] Preferably, the oxygen separated in step 2.4 is circulated to the reactor.

[0019] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: 1. When the copper-based catalyst of the present invention is used for catalytic preparation of chlorine from hydrogen chloride and oxygen, the copper-based catalyst catalytically oxidizes hydrogen chloride to form a mixed gas, and then separates gases other than chlorine in the mixed gas and distills to obtain liquid chlorine. Compared with other existing catalysts on the market, the copper-based catalyst has a high reaction space velocity, a space-time yield (STY) greater than 5.6 gcl2 / gcat·h, a hydrogen chloride conversion rate of ≥93wt%, a high hydrogen chloride conversion rate, a small amount of catalyst, and a lower cost of the copper-based catalyst, so that the entire process is short, energy consumption is low, and operating costs are low.

[0020] 2. When the copper-based catalyst of the present invention is used for catalytic preparation of chlorine by hydrogen chloride and oxygen, the reactor temperature is controlled at 260-400°C, and the high-temperature mixed gas in this temperature range can be directly cooled to the target temperature through a quenching tower without first cooling through a cooler, thereby further reducing the investment cost; at the same time, distilled water can be introduced into the quenching tower to absorb unreacted hydrogen chloride gas, thereby simultaneously achieving the purpose of cooling and removing hydrogen chloride.

[0021] 3. When the copper-based catalyst of the present invention is used to catalytically prepare chlorine from hydrogen chloride and oxygen, hydrogen chloride gas and oxygen are mixed and introduced into a reactor for catalytic oxidation to form chlorine gas and water vapor, and heat is released. The heat released during the reaction is removed by a thermal cycle device, so that the temperature of the reactor can be controlled within a required range. At the same time, the heat is transferred to the waste heat boiler to heat the distilled water introduced into the preheating boiler and form steam. The steam returns to the preheater to preheat the hydrogen chloride gas and oxygen, thereby making full use of the heat generated during the reaction and reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The invention relates to a schematic diagram of a system structure for producing chlorine by using hydrogen chloride and oxygen.

[0023] Description of the drawings: 1-preheater, 2-waste heat boiler, 3-heat cycle device, 4-reactor, 5-quenching tower, 6-drying tower, 7-compressor, 8-condenser, 9-chlorine distillation tower. DETAILED DESCRIPTION

[0024] In order to further understand the content of the present invention, the present invention is described in detail in conjunction with examples. The following examples are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0025] Example 1 See attached Figure 1 As shown, the present invention relates to a copper-based catalyst used in catalytically preparing chlorine with hydrogen chloride and oxygen, and the preparation process comprises the following steps: Step 1. Charge hydrogen chloride gas B and oxygen A into a preheater 1 for mixed preheating, the molar ratio of hydrogen chloride gas B to oxygen A is 1:0.5, and after preheating to 200-335°C, the mixed gas C is input into a reactor 4 equipped with a copper-based catalyst, the reactor 4 is a single reactor or multiple reactors in parallel, catalytically oxidizes the hydrogen chloride gas to form chlorine and water vapor, and releases heat. The chemical equation for the reaction heat is: The copper catalyst is Cu 10 Ni4Mo1La3Bi3V1 is loaded on a catalyst carrier, the catalyst carrier is α-Al2O3 microcrystals, and the preparation process includes: A solution of a copper compound, a nickel compound, a molybdenum compound, a lanthanum compound, a bismuth compound and a vanadium compound is loaded on a catalyst carrier, and heated and decomposed to obtain copper atoms, nickel atoms, molybdenum atoms, lanthanum atoms, bismuth atoms and vanadium atoms, which are loaded on the catalyst carrier to obtain Cu 10 Ni4Mo1La3Bi3V1; In this embodiment, the copper compound is copper chloride, the nickel-containing compound is nickel nitrate hexahydrate, the molybdenum-containing compound is ammonium molybdate, the lanthanum-containing compound is lanthanum chloride, the bismuth-containing compound is bismuth nitrate, and the vanadium-containing compound is vanadium dichloride; the preparation process of the copper-based catalyst includes: (1) Add copper chloride, nickel nitrate hexahydrate, ammonium molybdate, lanthanum chloride, bismuth nitrate and vanadium dichloride into pure water at a molar ratio of 10:4:1:3:3:1 and stir to fully dissolve them. Then, α-Al2O3 microcrystals are immersed in the mixture for 24 hours. The α-Al2O3 microcrystals account for 60% of the total mass and the other components account for 40% of the total mass. (2) Filter the impregnated α-Al2O3 microcrystals and dry them at 90°C for 12-24h; (3) Calcine the α-Al2O3 microcrystals at 480-500°C for 6-8 hours to obtain a copper-based catalyst, and extrude the shaped particles into particles with an average diameter of 0.1-0.5 mm.

[0026] About 98 wt% of hydrogen chloride is oxidized to chlorine under the action of the catalyst, and the whole reaction is an exothermic reaction. Therefore, the heat in the reactor 4 is removed through the heat circulation device 3, so that the temperature in the reactor 4 is controlled at 260-400°C and the pressure is controlled at 0-1.0 MPaG. The heat circulation device 3 adopts a molten salt circulation device or a pressurized heat transfer oil circulation device; the removed high-temperature medium H2 enters the waste heat boiler 2, and distilled water I is introduced into the waste heat boiler 2. After the distilled water I is heated, 2.3 MPaG saturated steam is produced as a by-product. Part of the steam returns to the preheater 1 for preheating the hydrogen chloride gas and oxygen, and the remaining steam J is discharged. The medium in the heat circulation device 3 is cooled when passing through the waste heat boiler 2, and the cooled medium H1 returns to the reactor 4 to absorb heat again; after catalytic oxidation, a high-temperature mixed gas D containing chlorine, water vapor, unreacted hydrogen chloride gas and oxygen is formed.

[0027] Step 2. Separate water vapor, incompletely reacted hydrogen chloride gas and oxygen, and distill to obtain liquid chlorine, specifically: Step 2.1. The high-temperature mixed gas D is output from the reactor 1 and enters the quench tower 5. The quench tower 5 is a single-stage quench tower or a multi-stage quench tower. The quench tower 5 quickly cools the high-temperature mixed gas and absorbs the unreacted hydrogen chloride gas in the mixed gas D. The temperature of the bottom of the quench tower 5 is controlled by a circulating cooler at 20-60°C. Pure water I is added to the top of the tower to absorb the hydrogen chloride gas, forming hydrochloric acid which is recovered from the bottom of the quench tower 5.

[0028] Step 2.2. After the hydrogen chloride gas is removed, the mixed gas E enters the drying tower 6 for drying to remove water vapor; the task of the drying tower 6 is to dry the wet mixed gas to a moisture content of <50ppm, specifically in the following manner: the mixed gas E is countercurrently contacted with 96-98% sulfuric acid L from the top of the tower, the moisture is absorbed by the sulfuric acid, the heat of dissolution of the sulfuric acid is removed by the circulating cooler, and the dilute sulfuric acid M in the bottom of the tower is discharged and recovered through liquid level control.

[0029] Step 2.3. The dried mixed gas F is sequentially introduced into the compressor 7 and the condenser 8 for compression and condensation. The compressor 7 compresses the dried mixed gas to 1-1.5 MPaG, and the condenser 8 cools it to -20-60°C.

[0030] Step 2.4. The compressed and condensed mixed gas F is introduced into a chlorine distillation tower 9. The bottom temperature of the chlorine distillation tower 9 is controlled at 60-90°C, and the top temperature is controlled at -20-60°C. The function of the chlorine distillation tower 9 is to separate oxygen and obtain high-purity chlorine liquid. The separated oxygen A is circulated from the top of the distillation tower to the preheater, and finally enters the reactor for continued catalytic oxidation. The high-purity chlorine liquid G is collected from the bottom of the chlorine distillation tower 9.

[0031] Example 2 The difference between this embodiment and embodiment 1 is that the raw materials for preparing the copper-based catalyst are different. In this embodiment, the copper compound is copper nitrate, the nickel-containing compound is nickel nitrate, the molybdenum-containing compound is ammonium molybdate, the lanthanum-containing compound is lanthanum nitrate, and the bismuth-containing compound and the vanadium-containing compound are bismuth vanadate.

[0032] About 93.7 wt% of hydrogen chloride is oxidized to chlorine gas under the action of the copper-based catalyst.

[0033] Example 3 The difference between this embodiment and embodiment 1 is that the ratio of each component is different when preparing the copper-based catalyst. In this embodiment, cupric chloride, nickel nitrate hexahydrate, ammonium molybdate, lanthanum chloride, bismuth nitrate and vanadium dichloride are added into pure water in a molar ratio of 9:5:0.5:2:2.5:0.5 and stirred to make them fully dissolved and then immersed in α-Al2O3 microcrystals for 24 hours. The α-Al2O3 microcrystals account for 60% of the total mass, and other components account for 40% of the total mass.

[0034] About 95.5 wt % of hydrogen chloride is oxidized to chlorine gas under the action of the copper-based catalyst.

[0035] Example 4 The difference between this embodiment and embodiment 1 is that the process conditions for preparing the copper-based catalyst are different. In this embodiment, the preparation process of the copper-based catalyst includes: (1) Add copper chloride, nickel nitrate hexahydrate, ammonium molybdate, lanthanum chloride, bismuth nitrate and vanadium dichloride into pure water at a molar ratio of 10:4:1:3:3:1 and stir to fully dissolve them. Then, α-Al2O3 microcrystals are immersed in the mixture for 12 hours. The α-Al2O3 microcrystals account for 60% of the total mass and the other components account for 40% of the total mass. (2) Filter the impregnated α-Al2O3 microcrystals and dry them at 100°C for 12-24h; (3) Calcine the α-Al2O3 microcrystals at 500-600°C for 6-8 hours to obtain a copper-based catalyst, and extrude the shaped particles into particles with an average diameter of 0.1-0.5 mm.

[0036] About 97.3 wt% of hydrogen chloride is oxidized to chlorine gas under the action of the copper-based catalyst.

[0037] Effect example This effect example compares the effect of using the copper-based catalysts of Examples 1-4 and common catalysts (CexMn1-xO2 and Cu-X-KZr-Ga-O) to produce chlorine. The effect comparison is shown in Table 1. Table 1: Chlorine production comparison table Hydrogen chloride conversion rate (wt%) Space-time yield (gcl2 / gcat·h) <![CDATA[Space velocity (h -1 ).]]> Embodiment 1 (best) 98 9.33 7500～20000 Example 2 93.7 9.11 7500～20000 Example 3 95.5 9.03 7500～20000 Example 4 97.3 9.25 7500～20000 <![CDATA[CexMn1-xO2(CN113135552A)]]> 57.7 / 4000～20000 Cu-X-KZr-Ga-O (CN108928803A) 80 2.53 300～2000 It can be seen from the above table that after using the copper-based catalyst of the present invention, the reaction space velocity, space-time yield, hydrogen chloride conversion rate, etc. are significantly improved.

[0038] The present invention is described in detail above in conjunction with the embodiments, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of application of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A copper-based catalyst, which is loaded on a catalyst carrier, the catalyst carrier is α-Al2O3 microcrystals, and the preparation process thereof comprises: A solution of a copper compound, a nickel compound, a molybdenum compound, a lanthanum compound, a bismuth compound and a vanadium compound is loaded on a catalyst carrier, and heated and decomposed to obtain copper atoms, nickel atoms, molybdenum atoms, lanthanum atoms, bismuth atoms and vanadium atoms, which are loaded on the catalyst carrier to obtain Cu 10 Ni4Mo1La3Bi3V1.

2. The copper-based catalyst according to claim 1, characterized in that: The copper compound is copper chloride or copper nitrate, the nickel-containing compound is nickel nitrate hexahydrate or nickel nitrate, the molybdenum-containing compound is ammonium molybdate, the lanthanum-containing compound is lanthanum nitrate or lanthanum chloride, the bismuth-containing compound is bismuth nitrate or bismuth vanadate, and the vanadium-containing compound is one of bismuth vanadate, indium vanadate, silver vanadate, iron vanadate, and vanadium dichloride.

3. The copper-based catalyst according to claim 2, characterized in that: The copper compound is copper chloride, the nickel-containing compound is nickel nitrate hexahydrate, the molybdenum-containing compound is ammonium molybdate, the lanthanum-containing compound is lanthanum chloride, the bismuth-containing compound is bismuth nitrate, and the vanadium-containing compound is vanadium dichloride; the preparation process of the copper-based catalyst includes: (1) Add copper chloride, nickel nitrate hexahydrate, ammonium molybdate, lanthanum chloride, bismuth nitrate and vanadium dichloride into pure water at a molar ratio of 10:4:1:3:3:1 and stir to fully dissolve them, then immerse α-Al2O3 microcrystals for 12-24 hours; (2) filtering the impregnated α-Al2O3 microcrystals and drying them at 80-100°C for 12-24 hours; (3) Calcine the α-Al2O3 microcrystals at 480-600°C for 6-8 hours to obtain a copper-based catalyst, and extrude the shaped particles into particles with an average diameter of 0.1-0.5 mm.

4. The copper-based catalyst according to claim 1 is used for catalytic production of chlorine from hydrogen chloride and oxygen.

5. The copper-based catalyst according to claim 4 is used to catalyze the preparation of chlorine by hydrogen chloride and oxygen, characterized in that: It includes the following steps: Step 1. After the hydrogen chloride gas and oxygen are mixed, they are input into a reactor equipped with a copper-based catalyst. The reactor temperature is 260-400°C and the pressure is 0-1.0MpaG to catalytically oxidize the hydrogen chloride gas to form chlorine and water vapor; Step 2: Separate water vapor, incompletely reacted hydrogen chloride gas and oxygen, and distill to obtain liquid chlorine.

6. The copper-based catalyst according to claim 5 is used to catalyze the preparation of chlorine by hydrogen chloride and oxygen, characterized in that: The step 2 specifically includes: Step 2.

1. The high-temperature mixed gas formed after catalytic oxidation is passed into a quenching tower, which rapidly cools the high-temperature mixed gas and absorbs unreacted hydrogen chloride gas; Step 2.

2. The mixed gas after the removal of hydrogen chloride gas enters a drying tower for drying, and the drying tower absorbs water vapor through concentrated sulfuric acid in countercurrent contact with the mixed gas after the removal of hydrogen chloride gas; Step 2.

3. The dried mixed gas is sequentially introduced into a compressor and a condenser for compression and condensation; Step 2.

4. The compressed and condensed mixed gas is passed into a chlorine distillation tower to separate oxygen and distill to obtain liquid chlorine.

7. The copper-based catalyst according to claim 5 is used to catalyze the preparation of chlorine by hydrogen chloride and oxygen, characterized in that: In the step 2.1, the temperature of the quenching tower is controlled at 20-60° C. by a circulating cooler, and distilled water is introduced into the top of the quenching tower. The distilled water absorbs unreacted hydrogen chloride gas to form hydrochloric acid which is recovered from the bottom of the quenching tower.

8. The copper-based catalyst according to claim 5 is used to catalyze the preparation of chlorine by hydrogen chloride and oxygen, characterized in that: In step 1, the molar ratio of hydrogen chloride gas to oxygen is 1:0.25-1:1, hydrogen chloride gas and oxygen are introduced into a preheater to be mixed and preheated, and then introduced into a reactor equipped with a copper catalyst after preheating, and the temperature of the mixed gas after preheating is 200-350°C; the hydrogen chloride gas releases heat when catalytically oxidized in the reactor, and the heat is transferred out of the reactor through the medium in the heat circulation device and enters the waste heat boiler, and distilled water is introduced into the waste heat boiler, and the distilled water is heated to form steam and returns to the preheater for preheating hydrogen chloride gas and oxygen, and the medium returns to the reactor to reabsorb heat; the heat circulation device is a molten salt circulation device or a pressurized heat transfer oil circulation device; The temperature in the reactor of step 1 is 335-350° C. and the pressure is 0.2-0.6 MpaG.

9. The copper-based catalyst according to claim 5 is used to catalyze the preparation of chlorine by hydrogen chloride and oxygen, characterized in that: In the step 2.3, the compressor compresses the dried mixed gas to 1-1.5 MPaG, and the condenser cools it to -20--60°C; in the step 2.4, the bottom temperature of the chlorine distillation tower is controlled at 60-90°C, and the top temperature is controlled at -20--60°C.

10. The copper-based catalyst according to claim 5 is used to catalyze the preparation of chlorine by hydrogen chloride and oxygen, characterized in that: The oxygen separated in step 2.4 is circulated to the reactor.

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