CN103276412B - A kind of method and electrolyzer thereof preparing copper powder or nickel powder - Google Patents

Abstract

The invention discloses a kind of method and the electrolyzer thereof of preparing copper powder or nickel powder, continuous, large-scale production can be realized.The method step: preparation electrolytic solution; To treat that powder process clipped wire or turning scrap are cleared up, obtain raw metal; Raw metal, as sacrificial anode, loads in electrolysis basket, electrolysis; The aaerosol solution of continuous releasing metal powder and electrolytic solution, filtering separation metal powder; The metal powder washed with de-ionized water of filtering separation; Metal powder vacuum-drying; By dried metal powder mechanical grinding grinding grain; The examination and test of products.This device by electrolyzer, cathode sets plate, conduction main shaft, ceramic bearing, running contact, insulating coupling, decelerator, anode basket, support, scrape and whitewash, separator tank, connect acid proof pump and header tank forms.Compact construction of the present invention, compared with designing with the pulley type of same volume electrolyzer, active cathodic area improves more than 5 times, has increased substantially working efficiency, has reduced labour intensity.

Description

A method for preparing copper powder or nickel powder and its electrolysis device

technical field

The invention relates to a method for preparing metal powder by electrolysis and a device thereof, in particular to a method for preparing copper powder or nickel powder and an electrolysis device thereof.

Background technique

As an emerging material, fine metal powder has attracted widespread attention and produced many preparation methods. Each method has obvious advantages and disadvantages. Judging from the current situation, the electrolysis method is one of the most promising methods to realize industrialization. The metal powder prepared by the electrolytic method has high purity, good compaction performance, and easy control of particle size. It can obtain fine metal powder that is difficult to prepare by other methods, and is more suitable for preparing metal powder with high electronegativity.

In conventional electrolytic powder production, it is necessary to periodically scrape the powder, which not only reduces the production efficiency, but also the metal powder will continue to grow on the cathode plate, making it difficult to produce fine powder. In order to obtain fine metal powders, some studies have been carried out on the preparation of fine powders by electrolysis. Public literature: Xu Ruidong, Chang Shiying, Guo Zhongcheng, Research on the process and performance of ultrafine copper powder prepared by electrolysis [J], "Electronic Technology", 2006, 27(6):355-359; Zheng Wu, copper powder Research on electrolytic preparation process [J], "Powder Metallurgy Industry", 2001, 11(6):26-29. He Feng, Zhang Zhengyi, A New Electrolytic Method for Preparation of Ultrafine Metal Powder[J], "Acta Metallica Sinica", 2000, 36(6):659-661; Li Miao, Yu Jiansheng, Jiang Yu, etc., Preparation of Nano-copper by Ultrasonic Electrodeposition Mechanism study of powder [J], "Material Development and Application", 2004, 19(03):12-15; Duan Xuechen, He Wei, Zhu Lei, New electrodeposition preparation and characterization of ultrafine copper powder [J], " Powder Metallurgy Materials Science and Engineering, 2009, 14(3):169-173; Xu Jianlin, Chen Jidong, etc., Preparation of Nano Copper Powder by Electrochemical Method [J], "Journal of Lanzhou University of Technology", 2008, 34(3):9 -11. The above-mentioned documents introduce ultrasonic waves and additives, and have achieved good results, and the prepared powder has reached a nano-scale particle size. However, it is still in the development stage, and more work needs to be done to achieve large-scale production.

Contents of the invention

The invention provides a method for preparing copper powder or nickel powder and an electrolysis device thereof, which can realize continuous and large-scale production.

A method for preparing copper powder or nickel powder, the method comprises the following steps:

a. Prepare electrolyte, prepare copper powder using copper sulfate electrolyte, copper sulfate pentahydrate as electrolyte, copper ion concentration 0.04 ~ 0.30mol/L, use sulfuric acid to adjust the hydrogen ion concentration of the aqueous solution to 1.13 ~ 3.39mol/L, then add Dispersant sodium hexametaphosphate, the amount added is 0.01-0.1% by mass fraction; nickel chloride electrolyte is used to prepare nickel powder, nickel chloride hexahydrate is used as electrolyte, nickel ion concentration is 0.04-0.1mol/L, and hydrochloric acid Adjust the acidity with ammonia water to pH = 4, then add the dispersant polyvinylpyrrolidone, the amount added is 0.05-0.1% by mass fraction, and inject the electrolyte solution into the electrolytic cell and the high level tank;

b. Clean the metal particles or turning chips to be powdered, and wash them with deionized water to obtain metal raw materials;

c. The cleaned metal raw material is used as a sacrificial anode, put it into the electrolysis basket, start the speed-regulating deceleration motor, the cathode starts to rotate, the roller brush starts to work, and the metal powder produced falls into the bottom of the electrolysis tank. As the electrolysis process proceeds, Add metal raw materials every 1 to 1.2 hours. The electrolysis process conditions for preparing copper powder are: pH=3~4, current density 5~10A/dm ² , 316 stainless steel plate as cathode, temperature 27-33°C, distance between plates 40-60mm;

d. After the powder is produced, release the suspension solution of metal powder and electrolyte continuously, filter and separate the metal powder, and return the electrolyte to the electrolytic tank through the high level tank to keep the liquid level of the electrolytic tank and the concentration of the electrolyte in balance;

e. The metal powder separated by filtration is washed with deionized water for three times;

f. Vacuum-dry the obtained metal powder, the vacuum degree is 10-50Pa, the drying temperature is 100-120°C, and the drying time is 1-2 hours;

g. The dried metal powder is mechanically ground and granulated, and then passed through a -325 mesh sieve. The powder under the sieve is the product, and the material on the sieve is re-electrolyzed;

h. The above-mentioned metal powder products shall be inspected according to relevant standards, and the inspection contents are: metal powder content, oxygen content, powder particle size and bulk density.

A kind of device that the method for preparing copper powder or nickel powder adopts, and this device composition and structure are as follows:

Inside the electrolytic cell (4), a cathode group plate (5) is housed, and the cathode group plate (5) is made of a group of stainless steel plates connected in series, and is fixed on the conductive main shaft (12) equidistantly, and the conductive main shaft (12) is formed by It is made of stainless steel, coated with acid-resistant insulating material on the outside, supported by acid-resistant sealed ceramic bearings (8) at both ends, and one end of the conductive spindle (12) is connected to the current collector (9) to realize the dynamic conduction process of the cathode, and the conductive spindle (12) The top end is connected with the insulating coupling (10), and the speed-regulating deceleration motor (11) that provides the driving force drives the cathode assembly plate (5) to rotate together, and its speed can be adjusted. There is a An anode basket (6) is made of engineering plastics, the anode basket (6) is lined with acid-resistant filter cloth, and the anode sacrificial material contained in the anode basket (6) is connected to the wire through graphite electrodes. The sacrificial anode material, the DC power supply, the current collector, the conductive main shaft (12) and the cathode assembly plate (5) form a circuit system in the electrolyte. There are rolling scraping brushes (13) fixed on the support (7) on both sides of each cathode group plate (5), which are made of engineering plastics and can scrape off the generated powder in time. A discharge valve, connected to the powder-liquid separation tank (1), the separation tank (1) to the acid-resistant pump (2), the acid-resistant pump (2) to the high-level tank (3), the high-level tank (3) to the electrolytic tank (4) .

Compared with the prior art, the present invention has remarkable beneficial effects embodied in:

A method for preparing copper powder or nickel powder and its electrolysis device provided by the invention retains the advantages of high purity powder prepared by electrolysis, good compaction performance, and easy control of particle size, and solves the need for periodic powder scraping in conventional electrolysis production The problem of improving the production efficiency and realizing the industrialization of the preparation of fine powder. The electrolysis device has a compact structure. Compared with the drum type design of the same volume electrolysis cell, the effective cathode area is increased by more than 5 times, which will greatly improve the work efficiency and reduce the labor intensity. It is very suitable for the production of fine powders such as copper and nickel.

Description of drawings

Fig. 1 is a schematic diagram of the structure of an electrolytic device used in a method for preparing copper powder or nickel powder.

Fig. 2 is a TEM image of copper powder prepared by a method for preparing copper powder or nickel powder.

Fig. 3 is a TEM image of nickel powder prepared by a method for preparing copper powder or nickel powder.

Detailed ways

The present invention will be described in detail below with examples in conjunction with the accompanying drawings.

Embodiment 1, as shown in Figure 1, a kind of method for preparing copper powder and device thereof are as follows:

a. prepare copper sulfate electrolyte, copper ion concentration 0.08mol/L, pH=3, the dispersant sodium hexametaphosphate added accounts for 0.1% of the mass percentage concentration of copper sulfate electrolyte;

b. Inject the prepared electrolyte into the electrolytic cell 4 and the high level tank 3;

c. Clean up "copper rice" or copper turning chips, and wash with deionized water;

d. The cleaned copper raw material is directly loaded into the electrolysis frame 6 as a sacrificial anode, and is electrolyzed through graphite electrodes. As the electrolysis process progresses, copper raw materials are added every 1 to 1.2 hours. The electrolytic process conditions are: current density 5A/ dm ² , the cathode group plate 5 is made of 316 stainless steel plate, the electrolysis temperature is 27-33°C, and the distance between the plates is 40-60mm;

e. Before the electrolysis begins, start the speed-regulating deceleration motor 11, the cathode assembly plate 5 starts to rotate, the scraper brush 13 starts to work, and the copper powder produced falls into the bottom of the electrolytic cell 4;

f. Continuously release the suspended solution of copper powder and electrolyte, filter and separate the copper powder in separation tank 1, and the electrolyte returns to electrolytic tank 4 through high position tank 3;

g. The copper powder separated by filtration is cleaned with deionized water, and cleaned three times;

h. Vacuum dry the copper powder, the vacuum degree is -20Pa, the drying temperature is 110°C, and the drying time is 1.5 hours;

i. The dry copper powder is mechanically ground and granulated, and sieved through a -325 mesh sieve. The powder under the sieve is the product, and the material on the sieve is re-electrolyzed;

j. Powder product composition and performance analysis, the above powder is tested according to relevant standards, copper content 99.7%, oxygen content 0.2%, particle size: 20-50nm, bulk density: 0.6g/cm3, compared with electrolytic copper powder GB/T5246- 1985 standard, meet the requirements. As shown in Figure 2, TEM image of copper powder.

Embodiment 2, as shown in Figure 1, a kind of method for preparing nickel powder and its electrolytic device are as follows:

a. Prepare nickel chloride electrolyte, use nickel chloride hexahydrate as electrolyte, adjust acidity with hydrochloric acid and ammonia water, nickel ion concentration is 0.04mol/L, pH=4, NH ₄ Cl is 10g/L, the added dispersant Polyvinylpyrrolidone accounts for 0.05% concentration of nickel chloride electrolyte mass percent;

b. Inject the prepared electrolyte into the electrolytic cell 4 and the high level tank 3;

c. Clean the nickel plate or recycled waste nickel block, and wash it with deionized water;

d. Cleaned nickel plate or reclaimed waste nickel block is directly loaded into the electrolysis frame 6 as a sacrificial anode, conducts electrolysis through graphite electrodes, and along with the electrolysis process, adds nickel raw materials every 1 to 1.2 hours, and the electrolysis process conditions are : The nickel plate is a sacrificial anode, the cathode group plate 5 is a pure copper plate, the current density is 8A/dm ² , the electrode distance is 30mm, and the solution temperature is 20°C;

e. Before the electrolysis begins, start the speed-regulating deceleration motor 11, the cathode assembly plate 5 starts to rotate, and the powder scraping brush 13 starts to work, and the nickel powder produced falls into the bottom of the electrolytic cell 4;

f. Continuously emit the suspension solution of nickel powder and electrolyte, filter and separate nickel powder in separation tank 1, and the electrolyte returns to electrolytic tank 4 through head tank 3;

g. the nickel powder separated by filtration is cleaned with deionized water, and cleaned three times;

h. Vacuum-dry the nickel powder, the vacuum degree is -20Pa, the drying temperature is 110°C, and the drying time is 1 hour;

i. The dried nickel powder is mechanically ground and granulated, and sieved through a 200 mesh sieve. The powder under the sieve is the product, and the material on the sieve is re-electrolyzed;

j. Powder product composition and performance analysis, the above-mentioned powder is inspected according to the relevant standards, the nickel content is 99.8%, the average particle size is 2.5 μm, the bulk density is 0.65g/cm3, compared with the electrolytic nickel powder GB5247-85 standard, it meets the requirements, such as As shown in Figure 3, the TEM image of nickel powder.

Claims (2)

1. prepare a method for copper powder or nickel powder, it is characterized in that the method comprises the following steps:

A. electrolytic solution is prepared, prepare copper powder and adopt copper sulfate electrolyte, take cupric sulfate pentahydrate as ionogen, copper ion concentration 0.04 ~ 0.30mol/L, aqueous solution hydrogen ion concentration is regulated to be 1.13 ~ 3.39mol/L with sulfuric acid, add sodium hexametaphosphate dispersant again, the amount added is massfraction 0.01 ~ 0.1%; Prepare nickel powder and adopt nickel chloride electrolyte, with six water nickelous chlorides for ionogen, nickel ion concentration is 0.04 ~ 0.1mol/L, acidity is regulated with hydrochloric acid and ammoniacal liquor, be adjusted to pH=4, add polyethylene of dispersing agent pyrrolidone again, the amount added is massfraction 0.05 ~ 0.1%, injects the electrolyte in electrolyzer and header tank;

B. will treat that powder process clipped wire or turning scrap are cleared up, by washed with de-ionized water, obtain raw metal;

C. cleaned raw metal is as sacrificial anode, load in electrolysis basket, start speed governing reducing motor, negative electrode starts to rotate, and round brush is started working, and the metal powder of generation falls into the bottom of electrolyzer, along with the carrying out of electrolytic process, within every 1 ~ 1.2 hour, add raw metal, preparing copper powder Electrolytic conditions is: pH=3 ~ 4, current density 5 ~ 10A/dm ², with 316 stainless steel plates for negative electrode, temperature 27-33 DEG C, polar plate spacing 40-60mm;

D. after powder produces, release the aaerosol solution of metal powder and electrolytic solution continuously, filtering separation metal powder, electrolytic solution returns electrolyzer through header tank, keeps liquid level of electrolyzer and concentration of electrolyte balance;

E. the metal powder washed with de-ionized water of filtering separation, cleans three times;

F. the metal powder vacuum-drying will obtained, vacuum tightness 10 ~ 50Pa, drying temperature 100 ~ 120 DEG C, 1 ~ 2 hour time of drying;

G. by dried metal powder mechanical grinding grinding grain, then mistake-325 mesh sieve, undersize powder is product, and screen overflow is electrolysis again;

H. above-mentioned metal-powder product is tested by relevant criterion, inspection content: metal-powder content, oxygen level, powder size and loose density.

2. the device that adopts of a kind of method preparing copper powder or nickel powder according to claim 1, it is characterized in that this device composition and structure as follows:

Inner at electrolyzer (4), cathode sets plate (5) is housed, cathode sets plate (5) is that the stainless steel plate of one group of series connection is made, equidistant being fixed on is conducted electricity on main shaft (12), conduction main shaft (12) is made up of stainless material, the acidproof insulating material of outside coating, two ends are supported by acid-resistant sealant ceramic bearing (8), conduction main shaft (12) one end is connected with running contact (9), realize the dynamic conducting process of negative electrode, the top of conduction main shaft (12) is connected with insulating coupling (10), the speed governing decelerator (11) of motivating force is provided to drive cathode sets plate (5) to rotate together, its rotating speed can regulate, an anode basket (6) is had in the middle of often adjacent cathode sets plate (5), employing engineering plastics are made, the acidproof filter cloth of anode basket (6) inside lining filling, the sacrificed anticathode material be contained in anode basket (6) is connected with wire through Graphite Electrodes, sacrificial anode material and direct supply, running contact, conduction main shaft (12) and cathode sets plate (5) forming circuit system in the electrolytic solution, have the rolling be fixed on support (7) to scrape in every block cathode sets plate (5) both sides to whitewash (13), employing engineering plastics are made, in time the powder of generation can be wiped off, a tapping valve is arranged at electrolyzer (4) bottom, connect powder liquid separator tank (1), separator tank (1) connects acid proof pump (2), acid proof pump (2) connects header tank (3), header tank (3) connects electrolyzer (4) again.