CN1399010A - Making process of durable stainless steel cathode plate for copper electrolyzing refining - Google Patents

Abstract

The invention relates to a method for preparing a copper electrolytic refining durable stainless steel cathode plate, belonging to the fields of nonferrous metal smelting and metal surface treatment. The cathode plate is made of 1Cr18Ni9Ti stainless steel, the surface is chemically oxidized or electrolytically oxidized to form a complete oxide film, and the edges are wrapped with engineering plastics (ABS). The formation of the oxide film on the surface makes the cathode copper have sufficient adhesion to the stainless steel plate, and is easy to peel off from it, and also improves the quality of the cathode, and improves the quality and current efficiency of the cathode copper. The use of the stainless steel cathode plate saves the process of making the initial electrode sheet from the traditional titanium seed plate, and can be used repeatedly.

Description

The preparation method of durable stainless steel cathode plate for copper electrolyzing refining

(1) technical field: non-ferrous metal metallurgy and field of metal surface treatment.

(2) background technology: in traditional electrolytic refining course of copper, negative electrode adopts copper starting sheet usually.Starting sheet the earliest is to cast after melting with electrolytic copper to form.After a while, most copper smelting plants all adopt the titanium plate to make starting sheet, promptly at the copper layer of the about 2～3mm of titanium starting sheet surface deposition, strip down then and add hangers as negative plate.This kind processing method needs complete and independent starting sheet production process and peels off processing units.

1979, Australian PERRY IAN JAMES invented the method that replaces traditional copper starting sheet with stainless steel cathode plate, and its patent No. is respectively GB2040311 and GB2104549.The negative plate that this patent is used is the stainless steel of the 316 L trades mark, and stainless steel composition (wt%) is a carbon (C) 0.03, nickel (Ni) 12.0, and chromium (Cr) 17.0, molybdenum (Mo) 2.25, all the other are iron (Fe).The stainless steel cathode plate surface reaches 2B smooth finish through polished finish.The bound edge material that negative plate the right and left uses is an acrylic plastering, and the base applies with wax.The weak point of this method is: (1) uses the stainless steel of the 316 L trades mark, that glossing comprises is cold rolling, dephosphorization, softening and on the polishing milling train multiple working procedure such as slight finish rolling, technology is numerous and diverse, starting material and tooling cost height; (2) acrylic plastering of Cai Yonging, a little less than its anti-oxidant and aging ability, work-ing life is short; (3) the stainless steel base adopts wax to apply, because wax is softer, bumps easily and takes off, and shield effectiveness is poor, and the wax recovery process is many, the cost height; (4) adopt the stainless steel of this trade mark, current efficiency has only 94.5%.

(3) summary of the invention

The present invention is exactly the weak point at above-mentioned patent, and a kind of preparation method of durable stainless steel cathode plate for copper electrolyzing refining is provided.The present invention realizes by following technical scheme.

Fig. 1 is a process flow sheet of the present invention.Stainless steel plate cuts to the negative plate size of regulation, then current conducting rod is welded on the stainless steel plate, whole plate is through after the polished finish, enter the subsequent oxidation treating processes, stainless steel plate after the oxidation promptly can be used as negative plate and enters electrolytic refining course of copper, reaches certain electrolysing period, and the cathode copper that meets product requirement gets off from the stainless steel sur-face peeling, and the packing warehouse-in, stainless steel cathode plate returns electrolytic refining course of copper to be continued to use.(1) stainless material of the present invention's employing

The stainless steel that the present invention adopts, its content (weight percent) is carbon (C) 0.09～0.12%, nickel (Ni) 9.0～10.0%, chromium (Cr) 17.0～18.0%, titanium (Ti) 0.65～0.75%, all the other are iron (Fe).(2) the stainless surface oxidation treatment method of the present invention

The stainless steel that the present invention uses must make its surface generate layer oxide film through oxide treatment, guarantees that the easy again and stainless steel of cathode copper and the existing good sticking power of stainless steel cathode plate peels off, and oxide thickness is 0.0005～0.010 millimeter (mm).The present invention both can adopt chemical oxidation also can adopt the electrolytic oxidation treatment process.The processing condition of chemical oxidation are: cerous nitrate [Ce (NO ₃) ₃] the 5-10 grams per liter, sodium-chlor (NaCl) 2-4 grams per liter, Sodium orthomolybdate (Na ₂MoO ₄) the 2-5 grams per liter, pH 1-4, solution temperature 25-50 ℃, oxidization time 20-30 minute.The processing condition of electrolytic oxidation are: citric acid (H ₃C ₆H ₅O ₇H ₂O) 20-50 grams per liter, boric acid (H ₃BO ₃) the 10-20 grams per liter, solution temperature 25-50 ℃, anodic current density 5-15 peace/square decimeter (A/dm ²), oxidization time 5-15 minute.(3) stainless steel cathode plate of the present invention's use adopts engineering plastics (ABS) bound edge, 15 millimeters of bound edge width (mm), 10 millimeters (mm) of height.

Compare advantage and the positively effect that is had with known technology: 1. stainless steel cathode plate of the present invention can save traditional starting sheet operation, effectively reduces production costs; 2. stainless steel cathode plate of the present invention allows to operate under higher current density, can reach 280～300 peace/square metre (A/m ²); 3. stainless steel cathode plate current efficiency height of the present invention can reach 97%; 4. stainless steel cathode plate bath voltage of the present invention is low, is 0.24～0.26 volt (V); 5. stainless steel cathode plate of the present invention, it uses and need not change the elementary operation parameter of existing copper electrorefining and the use of additive; 6. stainless steel cathode plate of the present invention, cost is low, low equipment investment, every block of plate (1 square metre) now needs about 800 yuan of Renminbi, significantly is lower than import plate price.

(4) description of drawings

Fig. 1 is a process flow sheet of the present invention.The 1st, stainless steel plate cutting, the 2nd, welding process, the 3rd, polishing process, the 4th, oxidation processes, the 5th, electrolytic process, the 6th, the peeling off of cathode copper, the 7th, cathode copper packing warehouse-in, the 8th, stainless steel cathode plate returns electrolytic process.

Fig. 2 is the structural representation of stainless steel cathode plate of the present invention.Among the figure 1 is stainless steel plate, and 2 is the ABS plastic bound edge, and 3 is current conducting rod.The inferior arc-welding of current conducting rod is received on the stainless steel plate, and bound edge adopts plastic pin to be connected on the stainless steel plate.

(5) embodiment

Embodiment one:

Electrolytic solution to certain copper smelting plant adopts negative plate of the present invention to carry out electrolysis.The processing condition that adopt are as follows:

Electrolytic solution is formed (grams per liter) copper sulfate (CuSO ₄) 45g/L; Sulfuric acid (H ₂SO ₄) 170g/L; Nickel (Ni)＜15g/L; Arsenic (As)＜15g/L; Antimony (Sb)＜0.5g/L; Iron (Fe)＜4g/L; Bismuth (Bi)＜0.3g/L; 60 ℃ of electrolyte temperatures; Go out under the circulation of elecrolyte mode is enterprising; Anode: the blister copper from this copper smelting plant is obtained consists of (weight percent) copper (Cu) 99.3～99.5; Foreign matter content: arsenic (As)≤0.08; Antimony (Sb)≤0.08; Bismuth (Bi)≤0.02; Nickel (Ni)≤0.09; Plumbous (Pb)≤0.07; Sulphur (S)≤0.01; Zinc (Zn)≤0.1; Tin (Sn) 0.0013～0.045; Iron (Fe) 0.0004～0.002; 0.24 volt of bath voltage (V); Current density 280 peace/square metre (A/m ²); 70 millimeters of homopolarity width between centers (mm).

Embodiment two:

Electrolytic solution under another processing condition is carried out electrolysis treatment.Concrete processing condition are:

Electrolytic solution is formed (grams per liter) copper sulfate (CuSO ₄) 55g/L; Sulfuric acid (H ₂SO ₄) 180g/L; Nickel (Ni)＜10g/L; Arsenic (As)＜10g/L; Antimony (Sb)＜0.5g/L; Bismuth (Bi)＜0.5g/L; 62 ℃ of electrolyte temperatures; Go out under the circulation of elecrolyte mode is enterprising; Anode: blister copper consists of (weight percent) copper (Cu) 99.2～99.7; Foreign matter content: arsenic (As)≤0.02; Antimony (Sb)≤0.08; Bismuth (Bi)≤0.026; Nickel (Ni)≤0.09; Plumbous (Pb)≤0.04; Sulphur (S)≤0.01; Oxygen (O)≤0.04; Selenium (Se)≤0.02; Silver (Ag)≤0.06; Gold (Au)≤0.003; Iron (Fe) 0.0001～0.001; Tin (Sn) 0.001～0.04; 0.26 volt of bath voltage (V); Current density 300 peace/square metre (A/m ²); 80 millimeters of homopolarity width between centers (mm).

According to above-mentioned processing condition electrolysis, when cathode deposition period reaches 8 days, obtain the electrolysis cathode copper of surfacing.Shake negative plate with hand hammer, electrolytic copper is the perk of slave plate face, is easy to the slave plate face and peels off.

Measure the weight of the cathode copper that electrolysis obtains with electronic balance, calculate current efficiency.The mean value of current efficiency is 97%.

The composition of the cathode copper that obtains with electron probe microanalysis (EPMA), the purity of copper can reach 99.97%.

This shows that the cathode copper purity height that adopts stainless steel cathode plate electrolysis of the present invention to obtain is easy to peel off from negative plate, and electrolytic process is stable, the current efficiency height.

Claims (4)

1. Adopt the preparation method of copper electrolytic refining durable stainless steel cathode plate of the present invention, it is characterized in that: the technological process of preparation is that stainless steel plate is cut to the cathode plate size of regulation, and conductive rod is welded on stainless steel plate, and stainless steel whole plate is polished after Oxidation treatment is carried out, and the stainless steel plate after oxidation treatment becomes a durable cathode plate for copper electrolytic refining. 2. the preparation method of copper electrolytic refining durable stainless steel cathode plate according to claim 1 is characterized in that: the stainless steel plate material composition (weight percentage) of adopting is: carbon (C) 0.09～0.12%, nickel (Ni) 9.0-10.0%, chromium (Cr)1 7.0-18.0%, titanium (Ti) 0.65-0.75%, and the rest is iron (Fe). 3. The preparation method of copper electrolytic refining durable stainless steel cathode plate according to claim 1, characterized in that: the oxidation treatment of cathode plate can adopt chemical treatment or electrolytic treatment method, and after oxidation treatment, a layer thickness is formed on its surface and is 0.0005～ 0.01 millimeter (mm) oxide film. The chemical oxidation process conditions are: cerium nitrate [Ce(NO ₃ ) ₃ ] _5-10 g/L, sodium chloride (NaCl) 2-4 g/L, sodium molybdate (Na ₂ MoO ₄ ) 2-5 g / liter, pH 1 ~ 4, solution temperature 25 ~ 50 degrees (℃), oxidation time 20 ~ 30 minutes, electrolytic oxidation treatment process conditions are: citric acid (H ₃ C ₆ H ₅ O ₇ ·H ₂ O) 20 ~ 50 g/L, boric acid (H ₃ BO ₃ ) 10-20 g/L, solution temperature 25-50 degrees (°C), anode current density 5-15 A/dm2 (A/dm ² ), oxidation time 5 ~15 minutes. 4. the preparation method of copper electrolytic refining durable stainless steel negative plate according to claim 1, is characterized in that: stainless steel negative plate adopts engineering plastics (ABS) to wrap, and wrapping width 15 millimeters (mm), height 10 millimeters ( mm).

Images