Method for improving antimony deposition quality on cathode surface

Abstract

The invention relates to the technical field of metallurgical electrochemistry, in particular to a method for improving the antimony deposition quality on the surface of a cathode, which comprises the following steps: polishing the surface of a stainless steel cathode, washing and drying to obtain a pretreated cathode; the pretreated cathode is subjected to sand blasting treatment, and the rough-surface cathode which is suitable for antimony electrodeposition nucleation and growth and has a certain granularity is obtained; the cathode with the rough surface is subjected to edge sealing treatment, and a standby cathode is obtained; the anode and the cathode to be used are put into the antimony-containing electrolyte, and the antimony deposition quality on the surface of the cathode is improved through electrolytic deposition treatment or electrolytic refining treatment. A sand blasting technology and an electrochemical deposition technology are combined, and according to nucleation and growth characteristics in an antimony electrolysis process, the surface of a stainless steel cathode is subjected to sand blasting treatment by adopting a sand blasting process, so that nucleation and growth of antimony atoms on the surface of the cathode are promoted, the binding force of an antimony deposition layer and the surface of the cathode is enhanced, and the grain growth stress is reduced; therefore, the electro-deposition quality of antimony on the surface of the cathode is effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical electrochemical technology, and in particular to a method for improving the antimony deposition quality on a cathode surface. Background Art

[0002] Stainless steel is widely used as cathode plate for metal electrodeposition due to its excellent corrosion resistance, good mechanical properties and excellent weldability. However, due to the weak Fe-Sb interface binding energy, the surface of the antimony cathode deposition layer is prone to cracking and falling off due to the large interface stress during long-period electrodeposition, which seriously affects the quality of the antimony deposition layer and the stability of the electrodeposition process, thereby causing abnormal electrolytic production.

[0003] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a method for improving the quality of antimony deposition on the cathode surface, aiming to solve the problem that the cathode antimony deposition layer is prone to cracking and falling off during the existing antimony electrolytic refining or electrolytic deposition process.

[0005] The technical solution of the present invention is as follows:

[0006] A method for improving the quality of antimony deposition on a cathode surface comprises the steps of:

[0007] The surface of the stainless steel cathode is polished, washed and dried to obtain a pre-treated cathode;

[0008] The pretreated cathode is subjected to sandblasting to obtain a cathode with a rough surface;

[0009] Performing edge sealing treatment on the rough-surface cathode to obtain a cathode to be used;

[0010] The anode and the cathode to be used are placed in an antimony-containing electrolyte, and the antimony deposition quality of the cathode surface is improved through electrolytic deposition treatment or electrolytic refining treatment.

[0011] The method for improving the quality of antimony deposition on the cathode surface, wherein the polishing treatment is performed using sandpaper with a mesh size of 600#-1000#.

[0012] The method for improving the quality of antimony deposition on the cathode surface, wherein the washing and drying comprises the steps of:

[0013] After the polished stainless steel cathode is ultrasonically cleaned or rinsed with water, it is secondary cleaned with anhydrous ethanol;

[0014] The stainless steel cathode after secondary cleaning is dried by using a hot air gun to obtain a pretreated cathode.

[0015] The method for improving the quality of antimony deposition on the cathode surface, wherein the purity of the anhydrous ethanol is greater than or equal to 99%; and the temperature of the hot air gun is less than or equal to 100°C.

[0016] The method for improving the quality of antimony deposition on the cathode surface, wherein the sandblasting treatment uses a sandblasting material with a particle size of 40#-100#; the sandblasting material is selected from one or more of quartz sand, alumina sand, and steel sand.

[0017] The method for improving the quality of antimony deposition on the cathode surface, wherein the pressure of the sandblasting treatment is 0.4MPa-0.6MPa, the distance of the sandblasting treatment is 10mm-14mm, and the angle of the sandblasting treatment is 45°±10°.

[0018] The method for improving the antimony deposition quality on the cathode surface, wherein, after the pre-treated cathode is sandblasted, the method further comprises: ultrasonically cleaning or rinsing the pre-treated cathode after sandblasting, and then performing a secondary cleaning with anhydrous ethanol and drying with a hot air gun;

[0019] Wherein, the purity of the anhydrous ethanol is greater than or equal to 99%; and the temperature of the hot air gun is less than or equal to 100°C.

[0020] The method for improving the antimony deposition quality on the cathode surface comprises the following steps: the rough-surface cathode is edge-sealed using an edge clip; the material of the edge clip comprises one of composite ABS, PPO, PE, and PP.

[0021] The method for improving the antimony deposition quality on the cathode surface, wherein the anode is a rough antimony plate or an inert anode plate.

[0022] The method for improving the quality of antimony deposition on the cathode surface, wherein the antimony concentration in the antimony-containing electrolyte is 40g / L-120g / L; the electrolysis temperature of the electrolytic deposition treatment or the electrolytic refining treatment is 20°C-80°C, and the current density of the electrolytic deposition treatment or the electrolytic refining treatment is 30A / m 2 -350A / m 2 .

[0023] Beneficial effects: The present invention provides a method for improving the quality of antimony deposition on the cathode surface, comprising the steps of grinding the surface of a stainless steel cathode, washing and drying to obtain a pre-treated cathode; sandblasting the pre-treated cathode to obtain a rough surface cathode with a certain particle size suitable for antimony electrodeposition nucleation and growth; edge sealing the rough surface cathode to obtain a standby cathode; placing the anode and the standby cathode in an antimony-containing electrolyte, and forming cathode metal antimony on the surface of the standby cathode through electrolytic deposition or electrolytic refining, thereby improving the quality of antimony deposition on the cathode surface. The present invention combines sandblasting technology with electrochemical deposition technology, and according to the nucleation and growth characteristics of the antimony electrolysis process, sandblasting the cathode surface is performed by sandblasting technology, so that a rough interface suitable for antimony electrodeposition nucleation and growth exists on the cathode surface, reducing the nucleation and growth energy barriers of antimony atoms on the cathode surface, enhancing the binding force between the antimony deposition layer and the cathode surface, and reducing the grain growth stress, thereby effectively improving the antimony electrodeposition quality on the cathode surface. This method can form a uniform and dense antimony deposition layer on the cathode surface, and the deposition layer has excellent bonding strength with the cathode, effectively solving the problems of cracking and falling off of the antimony deposition layer in traditional processes. At the same time, this method has the advantages of simple operation, low cost, and can significantly improve the current efficiency of the antimony electrolysis process and reduce the energy consumption of electrolysis. It is suitable for large-scale industrial production and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic flow chart of a method for improving the quality of antimony deposition on a cathode surface according to the present invention;

[0025] Figure 2 This is a microscopic characterization of the cathode antimony morphology obtained by electrodeposition in Example 1;

[0026] Figure 3 This is a microscopic characterization of the cathode antimony morphology obtained by electrodeposition in Example 2;

[0027] Figure 4 This is a microscopic characterization of the cathode antimony morphology obtained by electrodeposition in Example 3;

[0028] Figure 5 This is a microscopic characterization of the cathode antimony morphology obtained by electrodeposition without using the sandblasting process in Comparative Example 1. DETAILED DESCRIPTION

[0029] The present invention provides a method for improving the quality of antimony deposition on the cathode surface. In order to make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as herein.

[0031] In antimony smelting, stainless steel is often used as the cathode plate in the process of obtaining metallic antimony from antimony-containing solution by electroplating or electrolytic refining of crude antimony. Due to the small Fe-Sb interface bonding force and the large difference between the stainless steel grain size and the antimony grain size, the surface of the antimony cathode deposition layer is prone to cracking and falling off due to the large interface growth stress during long-term electrodeposition, thus causing abnormal electrolytic production. Therefore, in order to effectively solve these problems, it is necessary to enhance the bonding force between the stainless steel cathode surface and the antimony deposition and improve the nucleation and growth conditions of antimony atoms on the stainless steel cathode surface.

[0032] Based on this, Figure 1 As shown, the present invention provides a method for improving the antimony deposition quality on the cathode surface, comprising the steps of:

[0033] Step S10: grinding the surface of the stainless steel cathode, washing and drying it to obtain a pre-treated cathode;

[0034] Step S20: sandblasting the pretreated cathode to obtain a cathode with a rough surface;

[0035] Step S30: performing edge sealing treatment on the rough-surface cathode to obtain a cathode to be used;

[0036] Step S40: placing the anode and the cathode to be used in an antimony-containing electrolyte, and improving the antimony deposition quality on the cathode surface through electrolytic deposition treatment or electrolytic refining treatment.

[0037] In this embodiment, the sandblasting technology is combined with the electrochemical deposition technology. According to the nucleation and growth characteristics of the antimony electrolysis process, the cathode surface is sandblasted by the sandblasting process, thereby promoting the nucleation and growth of antimony atoms on the cathode surface, enhancing the bonding force between the antimony deposition layer and the cathode surface, and reducing the grain growth stress, thereby effectively improving the quality of antimony electrodeposition on the cathode surface. This method can form a uniform and dense antimony deposition layer on the cathode surface, and the deposition layer has excellent bonding force with the stainless steel cathode, effectively solving the problems of cracks and shedding of the antimony deposition layer in the traditional process; at the same time, this method has the advantages of simple operation, low cost, and can significantly improve the current efficiency of the antimony electrolysis process and reduce the energy consumption of electrolysis. It is suitable for large-scale industrial production and has broad application prospects.

[0038] Specifically, the present invention can effectively solve the problem of cracking and shedding of the cathode antimony deposition layer caused by insufficient Fe-Sb bonding force and large nucleation and growth stress on the surface of the antimony cathode deposition layer during the electrolytic refining of crude antimony or antimony electrolytic deposition by sandblasting the surface of the stainless steel cathode. The method of the present invention mainly includes the steps of: firstly grinding and washing and drying the surface of the stainless steel cathode to remove surface dirt, oxides and other impurities, and then using a sandblasting process to treat the pretreated cathode to ensure that the cathode has a certain roughness and surface granularity, reduce the energy barrier required for nucleation and growth of antimony on the cathode, reduce the growth stress of the antimony deposition layer, and enhance the bonding force between antimony and the cathode; this method can not only effectively reduce the problems of deposition cracking, warping, shedding, etc. that may occur during the antimony electrodeposition process, but also significantly reduce the antimony deposition overpotential, improve the current efficiency, and reduce the power consumption.

[0039] In some embodiments, the grinding process is performed using sandpaper with a mesh size of 600#-1000#. The surface of the stainless steel cathode is ground using sandpaper with a mesh size of 600#-1000# to remove the oxide layer and impurities attached to the cathode surface.

[0040] In a preferred embodiment, the surface of the stainless steel cathode is polished using 800# grit sandpaper, which can effectively remove the oxide layer and impurities while improving the polishing efficiency.

[0041] In some embodiments, in step S10, the washing and drying comprises the steps of: ultrasonically cleaning or rinsing the polished stainless steel cathode, and then performing a secondary cleaning with anhydrous ethanol; and drying the stainless steel cathode after the secondary cleaning with a hot air gun to obtain a pre-treated cathode. Ultrasonic cleaning or rinsing with clean water and secondary cleaning with anhydrous ethanol can remove the tiny particles and impurities remaining on the surface of the stainless steel cathode, and then drying with a hot air gun to ensure that there is no moisture or solvent residue on the surface.

[0042] In some embodiments, the purity of the anhydrous ethanol is greater than or equal to 99%; the temperature of the hot air gun is less than or equal to 100° C. High-purity anhydrous ethanol can better dissolve the tiny particles and impurities on the cathode surface, and then the hot air gun with a temperature less than or equal to 100° C. is used for drying, so that the water or solvent on the cathode surface can be evaporated.

[0043] In some embodiments, the sandblasting treatment uses a sandblasting material with a particle size of 40#-100#; the sandblasting material is selected from one or more of quartz sand, alumina sand, and steel sand. The pre-treated cathode surface is sandblasted using one or more of 40#-100# quartz sand, alumina sand, and steel sand, so that the cathode surface reaches a certain roughness and has a surface particle size suitable for antimony electrodeposition nucleation and growth.

[0044] In a preferred embodiment, the sandblasting process uses one of quartz sand, alumina sand and steel sand with a particle size of 60#.

[0045] In some embodiments, the sandblasting pressure is 0.4MPa-0.6MPa, the sandblasting distance is 10mm-14mm, and the sandblasting angle is 45°±10°. Under the sandblasting process parameters, the cathode surface can reach a certain roughness, so that the cathode surface has a surface particle size suitable for antimony electrodeposition nucleation and growth.

[0046] In a preferred embodiment, the pressure of the sandblasting treatment is 0.5 MPa, the distance of the sandblasting treatment is 12 mm, and the angle of the sandblasting treatment is 50°.

[0047] In some embodiments, after the pre-treated cathode is sandblasted, the method further includes: ultrasonically cleaning or rinsing the pre-treated cathode after sandblasting, performing secondary cleaning with anhydrous ethanol and drying with a hot air gun; wherein the purity of the anhydrous ethanol is greater than or equal to 99%; and the temperature of the hot air gun is less than or equal to 100° C. Cleaning the pre-treated cathode after sandblasting can remove tiny particles and impurities that may be attached during the sandblasting process, and then rinsing with anhydrous ethanol and drying with a hot air gun to ensure that the surface is clean and free of solvent residue.

[0048] In some embodiments, the rough-surface cathode is edge-sealed using an edge strip; the material of the edge strip includes one of composite ABS, PPO, PE, and PP.

[0049] In some embodiments, the anode is a crude antimony plate or an inert anode plate. Stainless steel has excellent corrosion resistance, good mechanical properties and excellent weldability, and is therefore the first choice for metal electrodeposition cathode plates. After stainless steel is treated by the method of the present invention, the stainless steel cathode plate can be guaranteed to have a certain roughness and surface granularity, reduce the energy barrier required for nucleation and growth of antimony on the stainless steel cathode, reduce the growth stress of the antimony deposition layer, and enhance the bonding force between antimony and the stainless steel cathode plate.

[0050] In some embodiments, the antimony concentration in the antimony-containing electrolyte is 40 g / L-120 g / L; the electrolysis temperature of the electrolytic deposition treatment or the electrolytic refining treatment is 20° C.-80° C., and the current density of the electrolytic deposition treatment or the electrolytic refining treatment is 30 A / m 2 -350A / m 2 .

[0051] In a preferred embodiment, the antimony concentration in the antimony-containing electrolyte is 70 g / L-90 g / L; the electrolysis temperature of the electrolytic deposition treatment or the electrolytic refining treatment is 40° C.-80° C., and the current density of the electrolytic deposition treatment or the electrolytic refining treatment is 100 A / m 2 -300A / m 2 .

[0052] This method can effectively solve the problem of cracking and shedding of the cathode antimony deposition layer caused by insufficient bonding between the stainless steel cathode and antimony and large nucleation and growth stress on the surface of the antimony cathode deposition layer during the electrolytic refining or electrolytic deposition of crude antimony. It can also significantly reduce the overpotential of antimony deposition, improve current efficiency, and reduce power consumption. In addition, this method has the advantages of simple process, simple operation, and small equipment investment, and is suitable for large-scale industrial production and has broad application prospects.

[0053] The following examples are further given to illustrate the present invention in detail. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention belong to the scope of protection of the present invention.

[0054] Example 1

[0055] The anode is a titanium plate coated with ruthenium and iridium. The cathode is a 304 stainless steel plate, which is polished with 800-grit sandpaper, ultrasonically cleaned in ultrapure water for 15 minutes, cleaned with anhydrous ethanol, and dried with a hot air gun. Quartz sand with a particle size of 60# is selected, the sandblasting pressure is 0.5Mpa, the sandblasting distance is 12mm, the sandblasting angle is 40°, and the anhydrous ethanol is cleaned for 3 minutes. The electrolyte is Sb 3+ (50g / L), NaOH (60g / L) and Na2S (40g / L), current density 300A / m 2 , electroplating temperature 60℃, distance between opposite poles 5.5cm, circulation speed 120mL / min, electroplating time 50h. Through the above treatment, a dense metal antimony deposition layer can be formed on the surface of 304 stainless steel plate. Figure 2 As shown, the cathode antimony purity is 98.51%.

[0056] Example 2

[0057] The anode is a titanium plate coated with ruthenium and iridium. The cathode is a 316L stainless steel plate, which is polished with 1000-grit sandpaper, rinsed with water for 15 minutes, cleaned with anhydrous ethanol, dried with a hot air gun, and selected 80# alumina sand, with a sandblasting pressure of 0.45Mpa, a sandblasting distance of 13mm, a sandblasting angle of 45°, and cleaned with anhydrous ethanol for 3 minutes. The electrolyte is Sb 3+(65g / L), NaOH (62g / L) and Na2S (39g / L), current density 350A / m 2 , electroplating temperature 50℃, distance between opposite poles 5.0cm, circulation speed 80mL / min, electroplating time 52h. Through the above treatment, a dense metal antimony deposition layer can be formed on the surface of 316 stainless steel. Figure 3 , the cathode antimony purity is 98.8%.

[0058] Example 3

[0059] The anode is made of crude antimony plate containing 96.5% antimony. The cathode is made of 316L stainless steel plate, which is polished with 700-grit sandpaper, ultrasonicated in ultrapure water for 10 minutes, cleaned with anhydrous ethanol, dried with a hot air gun, and selected 100# steel sand, with a sandblasting pressure of 0.55Mpa, a sandblasting distance of 12mm, a sandblasting angle of 45°, and cleaned with anhydrous ethanol for 3 minutes. The electrolyte is Sb 3+ (80g / L), H2SO4 (300g / L) and NH4F (100g / L), current density 240A / m 2 , electrolysis temperature 30℃, distance between opposite poles 4.5cm, circulation speed 120mL / min, electrolytic deposition time 72h. Through the above treatment, a dense metal antimony deposition layer can be formed on the surface of 316L stainless steel plate. Figure 4 , cathode antimony purity is 99.81%

[0060] Comparative Example 1

[0061] The anode is made of titanium plate coated with ruthenium and iridium. The cathode is made of 316L stainless steel. The electrolyte is made of Sb 3+ (65g / L), NaOH (62g / L) and Na2S (39g / L), current density 350A / m 2 , electroplating temperature 50℃, distance between opposite poles 5.0cm, circulation rate 80mL / min, electroplating time 52h. Through the above treatment, the metal antimony deposition layer generated on the surface of 316 stainless steel is as follows Figure 5 , the cathode antimony purity is 95.60%.

[0062] In summary, the present invention provides a method for improving the quality of antimony deposition on the cathode surface, including the steps of grinding the surface of a stainless steel cathode, washing and drying to obtain a pre-treated cathode; sandblasting the pre-treated cathode to obtain a rough surface cathode with a certain particle size suitable for antimony electrodeposition nucleation and growth; edge sealing the rough surface cathode to obtain a standby cathode; placing the anode and the standby cathode in an antimony-containing electrolyte, and forming cathode metal antimony on the surface of the standby cathode through electrolytic deposition or electrolytic refining, thereby improving the quality of antimony deposition on the cathode surface. The present invention combines sandblasting technology with electrochemical deposition technology, and according to the nucleation and growth characteristics of the antimony electrolysis process, sandblasting technology is used to sandblast the cathode surface, thereby promoting the nucleation and growth of antimony atoms on the cathode surface, enhancing the bonding force between the antimony deposition layer and the cathode surface, and reducing the grain growth stress, thereby effectively improving the antimony electrodeposition quality on the cathode surface. This method can form a uniform and dense antimony deposition layer on the cathode surface, and the deposition layer has excellent bonding strength with the cathode, effectively solving the problems of cracking and falling off of the antimony deposition layer in traditional processes. At the same time, this method has the advantages of simple operation, low cost, and can significantly improve the current efficiency of the antimony electrolysis process and reduce the energy consumption of electrolysis. It is suitable for large-scale industrial production and has broad application prospects.

[0063] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for improving the quality of antimony deposition on a cathode surface, characterized in that: Includes steps: The surface of the stainless steel cathode is polished, washed and dried to obtain a pre-treated cathode; The pretreated cathode is subjected to sandblasting to obtain a cathode with a rough surface; Performing edge sealing treatment on the rough-surface cathode to obtain a cathode to be used; The anode and the cathode to be used are placed in an antimony-containing electrolyte, and the antimony deposition quality of the cathode surface is improved through electrolytic deposition treatment or electrolytic refining treatment.

2. The method for improving the antimony deposition quality on the cathode surface according to claim 1, characterized in that: The grinding process is performed using sandpaper with a mesh size of 600#-1000#.

3. The method for improving the antimony deposition quality on the cathode surface according to claim 1, characterized in that: The washing and drying comprises the steps of: After the polished stainless steel cathode is ultrasonically cleaned or rinsed with water, it is secondary cleaned with anhydrous ethanol; The stainless steel cathode after secondary cleaning is dried by using a hot air gun to obtain a pretreated cathode.

4. The method for improving the antimony deposition quality on the cathode surface according to claim 3, characterized in that: The purity of the anhydrous ethanol is greater than or equal to 99%; the temperature of the hot air gun is less than or equal to 100°C.

5. The method for improving the antimony deposition quality on the cathode surface according to claim 1, characterized in that: The sandblasting process uses a sandblasting material with a particle size of 40#-100#; the sandblasting material is selected from one or more of quartz sand, alumina sand, and steel sand.

6. The method for improving the antimony deposition quality on the cathode surface according to claim 1, characterized in that: The pressure of the sandblasting treatment is 0.4MPa-0.6MPa, the distance of the sandblasting treatment is 10mm-14mm, and the angle of the sandblasting treatment is 45°±10°.

7. The method for improving the antimony deposition quality on the cathode surface according to claim 1, characterized in that: After the pre-treated cathode is sandblasted, the method further comprises: ultrasonically cleaning or rinsing the pre-treated cathode after the sandblasting, performing a secondary cleaning with anhydrous ethanol and drying with a hot air gun; Wherein, the purity of the anhydrous ethanol is greater than or equal to 99%; and the temperature of the hot air gun is less than or equal to 100°C.

8. The method for improving the antimony deposition quality on the cathode surface according to claim 1, characterized in that: The rough-surface cathode is edge-sealed by using an edge clip; the material of the edge clip includes one of composite ABS, PPO, PE, and PP.

9. The method for improving the antimony deposition quality on the cathode surface according to claim 1, characterized in that: The anode is a crude antimony plate or an inert anode plate.

10. The method for improving the antimony deposition quality on the cathode surface according to claim 1, characterized in that: The antimony concentration in the antimony-containing electrolyte is 40 g / L-120 g / L; the electrolysis temperature of the electrolytic deposition treatment or the electrolytic refining treatment is 20° C.-80° C., and the current density of the electrolytic deposition treatment or the electrolytic refining treatment is 30 A / m 2 -350A / m 2 .

Images