Method for preparing cuprous chloride from copper chloride

Abstract

The invention discloses a method for preparing cuprous chloride from copper chloride, and belongs to the technical field of vacuum preparation of cuprous chloride. The invention relates to a method for preparing cuprous chloride by using copper chloride, which comprises the following steps: carrying out microwave radiation heating on a mixed solution of CuCl2.H2O and CO (NH2) 2 under a vacuum condition, and respectively recovering generated CO2 and ammonia gas to obtain cuprous chloride; the temperature preservation stage of microwave radiation heating comprises three stages: in the first stage, the temperature is 10-25 DEG C, and the temperature is preserved for 10-30 minutes; the temperature of the second stage is 30-45 DEG C, and the heat preservation time is 15-35 minutes; and in the third stage, the temperature is 50-70 DEG C, and the heat preservation time is 15-45 minutes. The urea and the copper chloride solution are used as raw materials, and cuprous chloride with high purity and high yield can be obtained in a three-section heating and microwave radiation superposed manner. In addition, according to the preparation method of cuprous chloride, damage of covalent bonds of copper chloride can be accelerated, the decomposition temperature of copper chloride is reduced, and the reaction time is shortened.

Description

Technical Field

[0001] This invention relates to a method for preparing cuprous chloride using copper chloride, belonging to the field of vacuum preparation of cuprous chloride technology. Background Technology

[0002] Cuprous chloride appears as tetrahedral or white cubic crystals, presenting as a white or grayish-white powder. It is slightly soluble in water, easily photodegraded, toxic, and deliquescent. It is readily oxidized by air to basic cuprous chloride and reacts rapidly with water to form cuprous chloride hydrate. Cuprous chloride is commonly used as a catalyst in organic synthesis, polysilicon production, and rubber synthesis. Highly active cuprous chloride is a non-aggregated crystalline powder with a loose structure, large specific surface area, and exhibits small size effect, surface and interface effect, and quantum size effect. Nanoscale cuprous chloride synthesized through specific processes has wide applications in the metallurgical, pharmaceutical, and electroplating industries.

[0003] Traditional methods for producing cuprous chloride mainly include: direct oxidation of waste copper with chlorine gas: this method has high energy consumption, low product purity, and low equipment corrosion resistance, environmental protection, and production safety. Air oxidation of waste copper wire to produce cuprous chloride: this method is mainly characterized by slow reaction speed, equipment corrosion problems, strict operating conditions, large fluctuations in product quality, and potential environmental pollution. Although this method uses readily available raw materials and has relatively low costs, its production efficiency and environmental friendliness still need improvement. Summary of the Invention

[0004] To overcome the problems in the prior art, the present invention proposes a method for preparing cuprous chloride using copper chloride.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solution: A method for preparing cuprous chloride using copper chloride includes the following steps: A mixed solution of CuCl2·H2O and CO(NH2)2 was heated by microwave radiation under vacuum conditions, and the generated CO2 and ammonia were recovered to obtain cuprous chloride. The temperature holding stage of the microwave radiation heating includes three stages: the first stage has a temperature of 10-25℃ and a holding time of 10-30 min; the second stage has a temperature of 30-45℃ and a holding time of 15-35 min; and the third stage has a temperature of 50-70℃ and a holding time of 15-45 min. The three-stage heating superimposed with microwave radiation helps to improve the purity and yield of the product cuprous chloride. If the three-stage heating superimposed with microwave radiation is replaced with a single-stage heating microwave radiation, the purity and yield of the prepared cuprous chloride will decrease significantly, both falling below 60%.

[0006] Preferably, the microwave radiation frequency of the microwave radiation heating is 2-5 GHz, and the power is 300-1000 W.

[0007] Preferably, the molar ratio of CuCl2·H2O to CO(NH2)2 is 1.5:1.

[0008] Preferably, the particle size of CuCl2·H2O is 42-48μm, 32-38μm or 20-26μm.

[0009] Preferably, the vacuum degree of the vacuum condition is 0.1 MPa.

[0010] Preferably, after the third stage of heat preservation is completed, N2 is introduced and the temperature is lowered, with the N2 flow rate being 30 cm⁻¹. 3 / min.

[0011] The beneficial effects of this invention are as follows: This invention uses urea and copper chloride solution as raw materials, and employs a three-stage heating method combined with microwave radiation to obtain cuprous chloride with high purity and high yield. Furthermore, the method for preparing cuprous chloride described in this invention can accelerate the breaking of covalent bonds in copper chloride, lower the decomposition temperature of copper chloride, and shorten the reaction time. Attached Figure Description

[0012] Figure 1 The images shown are SEM images of the raw materials and products in Example 1, where (a) is an SEM image of cupric chloride dihydrate and (b) is an SEM image of cuprous chloride.

[0013] Figure 2 The image shows the XRD pattern of cuprous chloride prepared in Example 1. Detailed Implementation

[0014] The present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0015] Example 1 A method for preparing cuprous chloride using copper chloride includes the following steps: (1) Use a planetary ball mill to grind copper chloride dihydrate to a size of 42-48 μm. Weigh a certain amount of CuCl2·H2O and CO(NH2)2 according to a molar ratio of 1.5:1 to prepare a mixed aqueous solution of CuCl2·H2O and CO(NH2)2. The mass concentration of CuCl2·H2O in the mixed solution is 60%.

[0016] (2) A mixed solution of CuCl2·H2O and CO(NH2)2 was placed in a vacuum furnace, and the vacuum was adjusted to 0.1 MPa. Microwave radiation heating was performed at a frequency of 5 GHz and a power of 500 W. The temperature was controlled as follows: first stage: 20℃ for 20 min; second stage: 40℃ for 25 min; third stage: 60℃ for 30 min. A screen filter was installed between the vacuum pump and the vacuum extraction pipe. An absorption tower was installed at the exhaust port of the vacuum pump. The mixed gas (ammonia and carbon dioxide) entered the absorption tower from the bottom of the tower. Potassium carbonate solution was sprayed evenly onto the packing layer from the top of the tower through a liquid distributor. The gas came into countercurrent contact with the liquid absorbent during its ascent. Because the potassium carbonate solution has a strong chemical absorption capacity for carbon dioxide, the carbon dioxide was absorbed by the absorbent, while ammonia was relatively difficult to absorb. The gas (mainly ammonia) after absorption treatment was discharged from the top of the tower. The rich liquid that had absorbed carbon dioxide was discharged from the bottom of the tower and entered the subsequent treatment process.

[0017] (3) After the vacuum furnace is heated to 60°C and held for 30 minutes, inert nitrogen gas is introduced to protect cuprous chloride and cool the vacuum furnace. At the same time, the temperature is lowered to room temperature, all control valves are closed, the vacuum furnace is turned on, and cuprous chloride is removed.

[0018] In this embodiment, the conversion rate of cuprous chloride is 71%, and the purity of cuprous chloride is 72%.

[0019] like Figure 1 As shown, the crystal morphology of cupric chloride dihydrate is typically columnar, indicating a relatively unidirectional crystal growth and a rapid growth rate in a specific direction, resulting in a regular columnar shape and potentially uniform particle size distribution. SEM images of cuprous chloride may show different particle morphologies, such as blocky particles. Their relatively clean and neat surfaces indicate that impurities were effectively removed during the preparation process, resulting in a high-purity final product.

[0020] like Figure 2 As shown, cuprous chloride was successfully prepared in Example 1.

[0021] Example 2 The only difference between the method for preparing cuprous chloride using copper chloride in this embodiment and that in Example 1 is: The size of the copper chloride dihydrate after grinding in step (1) is 32-38 μm.

[0022] In this embodiment, the conversion rate of cuprous chloride is 83%, and the purity of cuprous chloride is 85%.

[0023] Example 3 The only difference between the method for preparing cuprous chloride using copper chloride in this embodiment and that in Example 1 is: The size of the copper chloride dihydrate after grinding in step (1) is 20-26 μm.

[0024] In this embodiment, the conversion rate of cuprous chloride is 92%, and the purity of cuprous chloride is 92%.

[0025] Example 4 A method for preparing cuprous chloride using copper chloride includes the following steps: (1) Use a planetary ball mill to grind copper chloride dihydrate to a size of 42-48 μm. Weigh a certain amount of CuCl2·H2O and CO(NH2)2 according to a molar ratio of 1.5:1 to prepare a mixed aqueous solution of CuCl2·H2O and CO(NH2)2. The concentration of CuCl2·H2O in the mixed solution is 60%.

[0026] (2) A mixed solution of CuCl2·H2O and CO(NH2)2 was placed in a vacuum furnace, and the vacuum was adjusted to 0.1 MPa. Microwave radiation heating was performed at a frequency of 5 GHz and a power of 1000 W. The temperature was controlled as follows: first stage: 10℃ for 30 min; second stage: 30℃ for 15 min; third stage: 70℃ for 15 min. A screen filter was installed between the vacuum pump and the vacuum extraction pipe. An absorption tower was installed at the exhaust port of the vacuum pump. The mixed gas (ammonia and carbon dioxide) entered the absorption tower from the bottom of the tower. The potassium carbonate solution was sprayed evenly onto the packing layer from the top of the tower through a liquid distributor. The gas came into countercurrent contact with the liquid absorbent during the ascent. Because the potassium carbonate solution has a strong chemical absorption capacity for carbon dioxide, the carbon dioxide was absorbed by the absorbent, while ammonia was relatively difficult to absorb. The gas (mainly ammonia) after absorption treatment was discharged from the top of the tower. The rich liquid that had absorbed carbon dioxide was discharged from the bottom of the tower and entered the subsequent treatment process.

[0027] (3) After the vacuum furnace is heated to 60°C and held for 30 minutes, inert nitrogen gas is introduced to protect cuprous chloride and cool the vacuum furnace. At the same time, the temperature is lowered to room temperature, all control valves are closed, the vacuum furnace is turned on, and cuprous chloride is removed.

[0028] In this embodiment, the conversion rate of cuprous chloride is 76%, and the purity of cuprous chloride is 78%.

[0029] Example 5 A method for preparing cuprous chloride using copper chloride includes the following steps: (1) Use a planetary ball mill to grind copper chloride dihydrate to a size of 42-48 μm. Weigh a certain amount of CuCl2·H2O and CO(NH2)2 according to a molar ratio of 1.5:1 to prepare a mixed aqueous solution of CuCl2·H2O and CO(NH2)2. The concentration of CuCl2·H2O in the mixed solution is 60%.

[0030] (2) A mixed solution of CuCl2·H2O and CO(NH2)2 was placed in a vacuum furnace, and the vacuum was adjusted to 0.1 MPa. Microwave radiation heating was performed at a frequency of 2 GHz and a power of 300 W. The temperature was controlled as follows: first stage: 25℃ for 10 min; second stage: 45℃ for 35 min; third stage: 50℃ for 45 min. A screen filter was installed between the vacuum pump and the vacuum extraction pipe. An absorption tower was installed at the exhaust port of the vacuum pump. The mixed gas (ammonia and carbon dioxide) entered the absorption tower from the bottom of the tower. Potassium carbonate solution was sprayed evenly onto the packing layer from the top of the tower through a liquid distributor. The gas came into countercurrent contact with the liquid absorbent during its ascent. Because potassium carbonate solution has a strong chemical absorption capacity for carbon dioxide, carbon dioxide was absorbed by the absorbent, while ammonia was relatively difficult to absorb. The gas (mainly ammonia) after absorption treatment was discharged from the top of the tower. The rich liquid that had absorbed carbon dioxide was discharged from the bottom of the tower and entered the subsequent treatment process.

[0031] (3) After the vacuum furnace is heated to 60°C and held for 30 minutes, inert nitrogen gas is introduced to protect cuprous chloride and cool the vacuum furnace. At the same time, the temperature is lowered to room temperature, all control valves are closed, the vacuum furnace is turned on, and cuprous chloride is removed.

[0032] In this embodiment, the conversion rate of cuprous chloride is 82%, and the purity of cuprous chloride is 84%.

[0033] Comparative Example 1 The only difference between the method for preparing cuprous chloride using copper chloride described in this comparative example and Example 1 is: The size of the copper chloride dihydrate after grinding in step (1) is 10-14 μm.

[0034] In this comparative example, the conversion rate of cuprous chloride was 43%, and the purity of cuprous chloride was 37%.

[0035] Comparative Example 2 A method for preparing cuprous chloride using copper chloride includes the following steps: (1) Use a planetary ball mill to grind copper chloride dihydrate to a size of 42-48 μm, and weigh a certain amount of CuCl2·H2O to prepare CuCl2·H2O solution; the concentration of CuCl2·H2O in CuCl2·H2O solution is 60%.

[0036] (2) Place the CuCl2·H2O solution in a vacuum furnace, adjust the vacuum degree to 0.1MPa, and perform microwave radiation heating. The microwave radiation frequency is 5GHZ, the power is 500W, and the temperature is controlled at 20℃ for 20min in the first stage, 40℃ for 25min in the second stage, and 60℃ for 30min in the third stage. Install a screen filter between the vacuum pump and the vacuum gas extraction pipe, and install an ammonia recovery device at the top of the vacuum pump and the exhaust pipe. Carbon dioxide is recovered from the top of the vacuum pump exhaust pipe and used as raw material for the electrolysis step with cuprous chloride.

[0037] (3) After the vacuum furnace is heated to 60°C and held for 30 minutes, inert nitrogen gas is introduced to protect cuprous chloride and cool the vacuum furnace. At the same time, the temperature is lowered to room temperature, all control valves are closed, the vacuum furnace is turned on, and cuprous chloride is removed.

[0038] In this comparative example, the conversion rate of cuprous chloride was 63%, and the purity of cuprous chloride was 64%.

[0039] Comparative Example 3 A method for preparing cuprous chloride using copper chloride includes the following steps: (1) Use a planetary ball mill to grind copper chloride dihydrate to a size of 42-48μm, and weigh a certain amount of mixed powder of CuCl2·H2O and CO(NH2)2 according to a molar ratio of 1.5:1.

[0040] (2) Place the mixed powder of CuCl2·H2O and CO(NH2)2 in a vacuum furnace, adjust the vacuum degree to 0.1MPa, and perform microwave radiation heating. The microwave radiation frequency is 5GHZ, the power is 500W, and the temperature is controlled at 20℃ for 20min in the first stage, 40℃ for 25min in the second stage, and 60℃ for 30min in the third stage. Install a screen filter between the vacuum pump and the vacuum gas extraction pipe, and install an ammonia recovery device at the top of the vacuum pump and the exhaust pipe. Carbon dioxide is recovered from the top of the vacuum pump exhaust pipe and used as raw material for the electrolysis step with cuprous chloride.

[0041] (3) After the vacuum furnace is heated to 60°C and held for 30 minutes, inert nitrogen gas is introduced to protect cuprous chloride and cool the vacuum furnace. At the same time, the temperature is lowered to room temperature, all control valves are closed, the vacuum furnace is turned on, and cuprous chloride is removed.

[0042] In this comparative example, the conversion rate of cuprous chloride was 68%, and the purity of cuprous chloride was 69%.

[0043] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A method for preparing cuprous chloride using copper chloride, characterized in that: The steps include: A mixed solution of CuCl2·H2O and CO(NH2)2 was heated by microwave radiation under vacuum conditions, and the generated CO2 and ammonia were recovered to obtain cuprous chloride. The temperature holding stage of the microwave radiation heating includes three stages: the first stage has a temperature of 10-25℃ and a holding time of 10-30 minutes; the second stage has a temperature of 30-45℃ and a holding time of 15-35 minutes; and the third stage has a temperature of 50-70℃ and a holding time of 15-45 minutes.

2. The method for preparing cuprous chloride using copper chloride according to claim 1, characterized in that: The microwave radiation frequency of the microwave heating is 2-5 GHz, and the power is 300-1000 W.

3. The method for preparing cuprous chloride using copper chloride according to claim 1, characterized in that: The molar ratio of CuCl2·H2O to CO(NH2)2 is 1.5:

1.

4. The method for preparing cuprous chloride using copper chloride according to claim 1, characterized in that: The particle size of the CuCl2·H2O is 42-48 μm, 32-38 μm or 20-26 μm.

5. The method for preparing cuprous chloride using copper chloride according to claim 1, characterized in that: The vacuum level of the vacuum condition is 0.1 MPa.

6. The method for preparing cuprous chloride using copper chloride according to claim 1, characterized in that: After the third stage of heat preservation is completed, N2 is introduced and the temperature is lowered. The flow rate of N2 is 30 cm³. 3 / min.

Images