Method for removing lead and supplementing nickel from electrodeposited nickel anolyte

Abstract

The invention discloses a method for removing lead and supplementing nickel from electrodeposited nickel anolyte, which relates to the technical field of nickel wet smelting, is used for purifying and removing lead from anolyte of a pure sulfuric acid system, and comprises the following steps of: adding the electrodeposited anolyte into refined nickel sulfate oil-removed liquid and nickel carbonate slurrying liquid, introducing air, controlling the temperature, and entering an acid dissolution lead removal tank for acid dissolution; and filtering the acid-dissolved solution through an acid dissolution filter press, pumping the obtained primary filtrate into a precision filter, pumping the obtained secondary filtrate into a secondary filtrate storage tank, pumping the secondary filtrate into a catholyte tank through a secondary filtrate delivery pump, and enabling the obtained catholyte as an electrodeposition cell catholyte to enter an electrodeposition process. The method has the advantages of being short in technological process, high in lead removal efficiency, simple and convenient to use, easy to filter, low in energy consumption, capable of recycling the falling solution, convenient for industrial production and the like.

Description

Technical Field

[0001] The invention relates to the technical field of nickel hydrometallurgy, in particular to a method for removing lead and replenishing nickel in an electrolytic nickel anode liquid. Background Art

[0002] At present, the production of lead in nickel electrolytic cathode liquid is mainly based on various mixed nickel concentrates with low nickel content. This type of nickel concentrate contains high impurities, including lead, zinc, arsenic and other impurity elements that affect the quality of electrolytic nickel products; at the same time, lead alloys are often used as insoluble anodes for electrolytic deposition in sulfate systems. Due to oxidation, the anode liquid contains trace amounts of lead. If the lead is not purified, these lead will precipitate on the cathode together with the main metal and affect the quality of the electrolytic metal. The produced electrolytic nickel also has the disadvantages of black surface and many bumps. For this reason, the anode liquid must be purified by lead removal so that the lead concentration in the new nickel electrolytic solution is required to be below 0.00035g / L, further optimizing the physical appearance and chemical quality of the electrolytic nickel. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for removing lead and replenishing nickel from an electrolytic nickel anolyte, which is used for purifying and removing lead from an anolyte in a pure sulfuric acid system to solve the problem of a single process corresponding to a single nickel-containing material.

[0004] The present invention provides a method for removing lead and replenishing nickel in nickel electrolytic anolyte, comprising the following steps: 1) Dissolution by acid at normal pressure.

[0005] Add refined nickel sulfate degreasing liquid and nickel carbonate slurry liquid to the electrolytic anode liquid, introduce air, and enter the acid dissolution lead removal tank for acid dissolution. The reaction temperature is controlled at 60-70 ℃. The acid-soluble lead removal tanks are 1# tank to 3# tank; the pH of 1# tank is controlled at 2.5-3.5, and the end point pH of 3# tank is controlled at 3.0-3.5; boric acid and barium carbonate are added to 3# tank of the acid-soluble lead removal tank.

[0006] The typical composition of refined nickel sulfate after degreasing is Ni 112.62g / l, Co 0.001g / l, Cu 0.0004g / l, Fe0.0004g / l, Zn0.0001g / l, Pb 0.00019g / l, As 0.00032g / l.

[0007] The typical composition of the electrolytic anolyte is Ni 50.28 g / l, Co 0.002 g / l, Cu 0.001 g / l, Fe 0.00055 g / l, Zn 0.00032 g / l, Pb 0.00016 g / l, and As 0.0001 g / l.

[0008] The typical composition of nickel carbonate slurry is Ni 67.05g / l, Co 0.002g / l, Cu 0.0015g / l, Fe0.0006g / l, Zn0.00035g / l, Pb 0.00022g / l, and As 0.0002g / l.

[0009] The volume ratio of refined nickel sulfate deoiled liquid, electrolytic anode liquid and nickel carbonate slurry liquid is 1:8:1. On the one hand, the acidity of the solution is used to mix and remove lead, and on the other hand, nickel ions are added to the system to prevent the depletion of nickel ions in the new electrolytic solution.

[0010] The amount of boric acid added is 1g / 200-400mL of electrolytic anode solution; the mass ratio of boric acid to barium carbonate is 6:1~3:1; boric acid can stabilize pH and play a buffering role, and at the same time can expand the bright density range of electrolytic nickel plates, making the nickel crystal arrangement more compact and delicate. Adding barium carbonate can remove lead, and at the same time, it can reduce the pH when the pH of the 1# tank is high.

[0011] 2) Primary filtration The acid-dissolved solution is transported to the acid-dissolved filter press through an acid-dissolved delivery pump for filtration, and the obtained primary filtrate enters the primary filtrate storage tank; the primary filter residue enters the primary filter residue slurry tank; The filtration area of ​​the acid filter press is 150m 2 The primary filtrate obtained after filtration contains Ni≥170g / L, and the primary filter residue contains Ni<6%.

[0012] 3) Secondary filtration The primary filtrate is pumped into the precision filter for secondary lead removal through the primary filtrate delivery pump, and the obtained secondary filtrate enters the secondary filtrate storage tank; the secondary filter residue returns to the anode liquid tank for purification treatment; Precision filter lead removal area is 300m 2 The typical components of the secondary filtrate obtained are Ni 56.68 g / l, Co 0.001 g / l, Cu 0.0004 g / l, Fe 0.0005 g / l, Zn 0.00016 g / l, Pb 0.00011 g / l, and As 0.0001 g / l.

[0013] 4) Residue slurrying The primary filter residue enters the primary filter residue slurrying tank and is mixed with the ground solution pumped in by the pit pump. After slurrying, it passes through the primary filter residue slurrying liquid delivery pump and returns to the anode liquid tank for purification treatment.

[0014] The beneficial effects of the present invention are as follows: the above method can be used to simply and effectively remove lead from a mixture of electrolytic anolyte, refined nickel sulfate degreasing solution, nickel carbonate slurry solution, etc., and the lead-containing impurities in the electrolytic anolyte are removed by using the acidic solution of the solution itself, while the electrolytic system is supplemented with nickel. Boric acid is used as a buffer to maintain the stability of the solution pH and prevent the nickel sulfate from being hydrolyzed. In addition, the presence of boric acid can also reduce the brittleness of the cathode nickel and make the surface of the nickel flat and smooth. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The present invention is a process flow chart for removing lead and replenishing nickel from the electrolytic nickel anode liquid. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0017] The main components of the electrolytic anode liquid, nickel sulfate degreasing liquid, and nickel carbonate slurry liquid selected in our experiment are shown in Table 1: Example 1 (1) Take 1600ml of electrolytic anolyte, add 200ml of nickel sulfate degreasing liquid and 200ml of nickel carbonate slurry, and put them into 1#~3# acid dissolution lead removal tanks for acid dissolution. The temperature is controlled at 65℃, the pH of 1# tank is controlled at 3, 6g of boric acid and 1g of barium carbonate are added to 3# tank, and the end point pH is controlled at 3.3.

[0018] (2) The acid-dissolved solution is transported to the acid-dissolved filter press through an acid-dissolved delivery pump for filtration. The primary filtrate is sent to the primary filtrate storage tank; the primary filter residue is sent to the primary filter residue slurry tank; the filtration area of ​​the acid-dissolved filter press is 150m 2 ; The primary filtrate obtained after filter pressing contains 176.56 g / L nickel, and the primary filter residue contains 5.2% nickel.

[0019] (3) Secondary filtration The primary filtrate is pumped into the precision filter for secondary lead removal through the primary filtrate delivery pump, and the obtained secondary filtrate enters the secondary filtrate storage tank; the secondary filter residue returns to the anode liquid tank for purification; the lead removal area of ​​the precision filter is 300m 2 The secondary filtrate obtained after precise filtration contained 58.61 g / l Ni, 0.001 g / l Co, 0.00035 g / l Cu, 0.00042 g / l Fe, 0.00015 g / l Zn, 0.00012 g / l Pb, and 0.00012 g / l As.

[0020] (4) Filter residue slurry The primary filter residue enters the primary filter residue slurrying tank and is mixed with the ground solution pumped in by the pit pump. After slurrying, it passes through the primary filter residue slurrying liquid delivery pump and returns to the anode liquid tank for purification treatment.

[0021] Example 2 (1) Take 1700 ml of electrolytic anode liquid, add 100 ml of nickel sulfate degreasing liquid and 200 ml of nickel carbonate slurry, and put them into 1#~3# acid dissolution lead removal tanks for acid dissolution. The temperature is controlled at 70 ℃, the pH of 1# tank is controlled at 2.5, and 5.5 g of boric acid and 1.5 g of barium carbonate are added to 3# tank. At this time, the end point pH is 3.

[0022] The acid-dissolved solution is transported to the acid-dissolved filter press through an acid-dissolved delivery pump for filtration. The primary filtrate is sent to the primary filtrate storage tank; the primary filter residue is sent to the primary filter residue slurry tank; the filtration area of ​​the acid-dissolved filter press is 150m 2 ; The primary filtrate obtained after filter pressing contains 170.54 g / L nickel, and the slag contains 5.9% nickel.

[0023] (3) Secondary filtration The primary filtrate is pumped into the precision filter for secondary lead removal through the primary filtrate delivery pump, and the obtained secondary filtrate enters the secondary filtrate storage tank; the secondary filter residue returns to the anode liquid tank for purification; the lead removal area of ​​the precision filter is 300m 2 ; The secondary filtrate obtained after precision filtration contained 56.24 g / l Ni, 0.0011 g / l Co, 0.00037 g / l Cu, 0.00052 g / l Fe, 0.00018 g / l Zn, 0.0001 g / l Pb, and 0.00011 g / l As.

[0024] Example 3 (1) Take 1600ml of electrolytic anode liquid, add 200ml of nickel sulfate degreasing liquid and 300ml of nickel carbonate slurry, and put them into 1#~3# acid dissolution lead removal tanks for acid dissolution. The temperature is controlled at 75℃, the pH of 1# tank is controlled at 3.5, 6.5g of boric acid and 2g of barium carbonate are added to 3# tank, and the end point pH is controlled at 3.5.

[0025] (2) The acid-dissolved solution is transported to the acid-dissolved filter press through an acid-dissolved delivery pump for filtration. The primary filtrate is sent to the primary filtrate storage tank; the primary filter residue is sent to the primary filter residue slurry tank; the filtration area of ​​the acid-dissolved filter press is 150m 2 The primary filtrate obtained after filter pressing contained 174.52 g / L nickel, and the slag contained 5.54% nickel.

[0026] (4) Filter residue slurry The primary filter residue enters the primary filter residue slurrying tank and is mixed with the ground solution pumped in by the pit pump. After slurrying, it passes through the primary filter residue slurrying liquid delivery pump and returns to the anode liquid tank for purification treatment.

[0027] (3) Secondary filtration The primary filtrate is pumped into the precision filter for secondary lead removal through the primary filtrate delivery pump, and the obtained secondary filtrate enters the secondary filtrate storage tank; the secondary filter residue returns to the anode liquid tank for purification; the lead removal area of ​​the precision filter is 300m 2 ; The secondary filtrate obtained after precise filtration contained 57.92 g / l Ni, 0.001 g / l Co, 0.00036 g / l Cu, 0.00048 g / l Fe, 0.00017 g / l Zn, 0.00011 g / l Pb, and 0.0001 g / l As.

[0028] (4) Filter residue slurry The primary filter residue enters the primary filter residue slurrying tank and is mixed with the ground solution pumped in by the pit pump. After slurrying, it passes through the primary filter residue slurrying liquid delivery pump and returns to the anode liquid tank for purification treatment.

Claims

1. A method for removing lead and replenishing nickel from nickel electrolytic anolyte, characterized in that: The method comprises the following steps: 1) Normal pressure acid dissolution Add refined nickel sulfate degreasing liquid and nickel carbonate slurry liquid to the electrolytic anode liquid, introduce air, and enter the acid dissolution lead removal tank for acid dissolution. The reaction temperature is controlled at 60-70°C. The acid-solution lead removal tanks are 1# tank to 3# tank; the pH of 1# tank is controlled at 2.5-3.5, and the end point pH of 3# tank is controlled at 3.0-3.5; boric acid and barium carbonate are added to 3# tank of the acid-solution lead removal tank; 2) Primary filtration The acid-dissolved solution is transported to the acid-dissolved filter press through an acid-dissolved delivery pump for filtration, and the obtained primary filtrate enters the primary filtrate storage tank; the primary filter residue enters the primary filter residue slurry tank; 3) Secondary filtration The primary filtrate is pumped into the precision filter for secondary lead removal through the primary filtrate delivery pump, and the obtained secondary filtrate enters the secondary filtrate storage tank; the secondary filter residue returns to the anode liquid tank for purification treatment; 4) Residue slurrying The primary filter residue enters the primary filter residue slurrying tank and is mixed with the ground solution pumped in by the pit pump. After slurrying, it passes through the primary filter residue slurrying liquid delivery pump and returns to the anode liquid tank for purification treatment.

2. The method for removing lead and replenishing nickel from electrolytic nickel anolyte according to claim 1, characterized in that: In step 1), the typical composition of the refined nickel sulfate after degreasing is Ni 112.62 g / l, Co 0.001 g / l, Cu 0.0004 g / l, Fe 0.0004 g / l, Zn 0.0001 g / l, Pb 0.00019 g / l, and As 0.00032 g / l.

3. The method for removing lead and replenishing nickel from electrolytic nickel anolyte according to claim 1, characterized in that: In step 1), the typical composition of the electrolytic anolyte is Ni 50.28 g / l, Co 0.002 g / l, Cu 0.001 g / l, Fe 0.00055 g / l, Zn 0.00032 g / l, Pb 0.00016 g / l, and As 0.0001 g / l.

4. The method for removing lead and replenishing nickel from electrolytic nickel anolyte according to claim 1, characterized in that: In step 1), the typical composition of the nickel carbonate slurry is Ni 67.05 g / l, Co 0.002 g / l, Cu 0.0015 g / l, Fe 0.0006 g / l, Zn 0.00035 g / l, Pb 0.00022 g / l, and As 0.0002 g / l.

5. The method for removing lead and replenishing nickel from electrolytic nickel anolyte according to claim 1, characterized in that: In step 1), the volume ratio of the refined nickel sulfate deoiled liquid, the electrodeposition anode liquid, and the nickel carbonate slurry liquid is 1:8:

1.

6. A method for removing lead and replenishing nickel from nickel electrolytic anolyte according to claim 1, characterized in that: In step 1), the amount of boric acid added is 1 g / 200-400 mL of the electrolytic anolyte; the mass ratio of boric acid to barium carbonate is 6:1-3:

1.

7. The method for removing lead and replenishing nickel from electrolytic nickel anolyte according to claim 1, characterized in that: In step 2), the filtration area of ​​the acid filter press is 150m 2 The primary filtrate obtained after filtration contains Ni≥170g / L, and the primary filter residue contains Ni<6%.

8. The method for removing lead and replenishing nickel from electrolytic nickel anolyte according to claim 1, characterized in that: In step 3), the lead removal area of ​​the precision filter is 300m 2 The typical components of the secondary filtrate obtained are Ni 56.68 g / l, Co 0.001 g / l, Cu 0.0004 g / l, Fe 0.0005 g / l, Zn 0.00016 g / l, Pb 0.00011 g / l, and As 0.0001 g / l.

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