US3437571A - Production of electrolytic nickel - Google Patents

Production of electrolytic nickel Download PDF

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Publication number
US3437571A
US3437571A US383888A US38388864A US3437571A US 3437571 A US3437571 A US 3437571A US 383888 A US383888 A US 383888A US 38388864 A US38388864 A US 38388864A US 3437571 A US3437571 A US 3437571A
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United States
Prior art keywords
nickel
cathode
electrolyte
sulfur
per liter
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Expired - Lifetime
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US383888A
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English (en)
Inventor
Louis S Renzoni
George Angelo Di Bari
Burton B Knapp
Francis X Carlin
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Huntington Alloys Corp
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International Nickel Co Inc
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Publication date
Application filed by International Nickel Co Inc filed Critical International Nickel Co Inc
Priority to US383888A priority Critical patent/US3437571A/en
Priority to SE00523/65A priority patent/SE327562B/xx
Priority to FI650123A priority patent/FI45995C/fi
Priority to NL6500944A priority patent/NL6500944A/xx
Priority to FR4692A priority patent/FR1432652A/fr
Priority to BE659469D priority patent/BE659469A/xx
Priority to AT127465A priority patent/AT257963B/de
Priority to ES0309323A priority patent/ES309323A1/es
Priority to DEJ27517A priority patent/DE1234999B/de
Priority to GB30786/65A priority patent/GB1056087A/en
Application granted granted Critical
Publication of US3437571A publication Critical patent/US3437571A/en
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C1/00—Electrolytic production, recovery or refining of metals by electrolysis of solutions
    • C25C1/06—Electrolytic production, recovery or refining of metals by electrolysis of solutions or iron group metals, refractory metals or manganese
    • C25C1/08—Electrolytic production, recovery or refining of metals by electrolysis of solutions or iron group metals, refractory metals or manganese of nickel or cobalt

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  • Electrolytic nickel having good appearance and good shearability in heavy sections and good chemical and electrochemical activity is produced by an electrorefining process wherein about 0.005 to about 0.25 gram per liter of sulfur dioxide and about 25 to about 75 milligrams per liter of a sulfur-free agent such as hydracrylonitrile are maintained in the electrorefining catholyte.
  • the present invention is directed to the electrorefining of nickel and, more particularly, to an improved method for producing electrolytic nickel or cathode nickel having good surface quality and having improved chemical and electrochemical activity.
  • the electrorefining cell employed is a compartmented cell divided into anode and cathode compartments by means of a permeable diaphragm and the electrolyte employed is a sulfate-chloride electrolyte.
  • the impure anode in the anode compartment is electrolytically corroded and substantially pure cathode nickel is deposited at a cathode in the cathode compartment as a result of electrolysis.
  • the impure anolyte is removed from the anode compartment at a steady rate and is subjected to purification treatments to remove therefrom impurities such as iron, copper, lead, arsenic, etc.
  • the purified electrolyte is then introduced at a steady rate into the cathode compartment and nickel of high purity is plated therefrom.
  • a slight hydrostatic head is maintained in the cathode compartment, allowing purified catholyte partly depleted in nickel to flow through the diaphragm into the anode compartment, thus preventing migration of unwanted ions from the impure anolyte in the anode compartment to the purified catholyte in the cathode compartment.
  • nickel and impurities are dissolved from the anode.
  • the impure anolyte is removed from the tanks, purified, and finally returned as purified catholyte to each cathode compartment for the deposition of pure nickel at each cathode.
  • cathode nickel is carried out commercially on a very large scale. For example, in one Canadian electrorefining installation the circulating rate of the electrolyte is approximately 300,000 gallons per hour. Because of the scale at which the operation is conducted and because of the necessity for producing electrolytic nickel under continuous conditions to produce a marketable product of high purity and having acceptable surface appearance, extremely careful control is required in all phases of the operation to insure that continuous production of cathodes can be maintained.
  • electrolytic nickel or cathode nickel having acceptable ductility, surface appearance and activity can be produced in an electrorefining operation by the addition of controlled amounts of a special combination of ingredients to the purified electrolyte.
  • Another object of the invention is to provide a special method for producing cathode nickel having improved activity and also having satisfactory surface appearance and ductility.
  • Still another object of the invention is to provide a method for producing cathode nickel having improved activity at an acceptable purity level.
  • a further object of the invention is to provide a method for producing smooth cathode nickel with minimum disruption of the electrorefining operation.
  • FIGURES 1 and 2 are reproductions of photographs taken at about 1 /2 diameters showing sheared pieces of electrolytic nickel produced outside the contemplation of the present invention
  • FIGURE 3 is a reproduction of a photograph taken at about 1 /2 diameters showing two sheared pieces of the activated shearable electrolytic nickel produced in accordance with the present invention.
  • FIGURE 4 is a reproduction of a photomicrograph taken at about 50 diameter depicting certain characterizing features found in the structure of the specialactivated electrolytic nickel produced in accordance with the teachings of the present invention.
  • the present invention contemplates a process for the production of electrolytic nickel cathodes which comprises electrolyzing an aqueous nickel electrorefining catholyte essentially devoid of impurities from the group consisting of copper, iron, arsenic and lead and containing a small amount, e.g., about 0.005 gram per liter, up to about 0.025 gram per liter of sulfur dioxide and a small amount, e.g., about 25 milligrams per liter up to not more than about milligrams per liter, of a sulfur-free leveling agent dissolved therein to produce sound, electrolytic nickel containing about 0.005% to about 0.025% sulfur substantially uniformly distributed therethrough.
  • a small amount e.g., about 0.005 gram per liter, up to about 0.025 gram per liter of sulfur dioxide and a small amount, e.g., about 25 milligrams per liter up to not more than about milligrams per liter, of a sulfur-free
  • the electrolyte contains about 0.01 to about 0.02 gram per liter of sulfur dioxide and the cathode nickel produced contains about 0.01% to about 0.02% sulfur.
  • the electrolysis is carried out while maintaining the electrolyte temperature between about F. and F. and while employing a cathode current density between about 5 and 25 amperes per square foot.
  • the electrorefining electrolyte may be the all-sulfate type, the all-chloride type, the all-sulfamate type, or may contain mixtures of these three salts.
  • the sulfate-chloride electrolyte is generally employed. It is to be appreciated that the process is applicable not only to the production of commercial electrolytic nickel conventionally having a thickness on the order of about inch to about /2 inch but it also is applicable to the production of the thin nickel cathode starting sheets employed in producing commercial cathode nickel. Such starting sheets are usually about 0.04 inch thick.
  • the leveling agent employed in accordance with the invention is a water-soluble organic cyanide or nitrile, i.e., a compound containing the CEN group attached to a carbon atom. More advantageously, such agents are employed in the ranges of about 30 to about 40 milligrams per liter of purified electrolyte.
  • Examples of such compounds are ethylene cyanohydrin (hydracrylonitrile) (CI-I II-ICH -CN), acetonitrile (CH ,CN), acrylonitrile (CH zCH CN), acetaldehyde cyanohydrin (CH CHOI-ICN) cyanoacetic acid acetone cyanohydrin (CH -COH-CN) propionitrile (CH CH -CN) 2-cyanoacetamide beta-chloropropionitrile (ClCH -CH CN), benzonitrile (C H CN), and para amino phenyl acetonitrile (NH C H CH -CN).
  • organic cyanides may be saturated or unsaturated, aliphatic or aromatic and may also contain a substituted group such as halogen, hydroxy, amino or carboxy group.
  • Another sulfur-free agent which may be employed along with or in place of organic cyanides is coumarin.
  • cathode nickel containing sulfur at the level of about 0.02% was quite inactive electrochemically and did not corrode smoothly, but rather became spongy, when subjected to electrochemical corrosion as, for example, in a conventional nickel plating bath. It had been found that an eX- pensive heat treatment at a high temperature on the order of 1500 F. to about 1800 F. was required in order to achieve an acceptable level of electrochemical activity in this prior cathode nickel product. It is believed that these prior observations resulted from and were due to a nonuniform or segregated occurrence of sulfur in the cathode nickel product.
  • the electrolytic nickel cathode produced in accordance with the present invention contains sulfur distributed therethrough in an essentially uniform manner and no heat treatment is required in order to provide a satisfactory level of electrochemical activity in the cathode nickel product even though the sulfur level is very low, e.g., about 0.02%.
  • active cathode nickel produced in accordance with the invention exhibits a negative potential on the order of about minus 0.1 volt as measured against a standard calomel electrode (S.C.E.) up to an anodic current density of about 150 amperes per square foot in an aqueous electrolyte containing about 70 grams per liter of nickel, about grams per liter of sulfate ion, about 30 grams per liter of boric acid, having a pH of about 4 and at a temperature of F.
  • commercial electrolytic nickel becomes passive at about one ampere per square foot.
  • cathode nickel produced in accordance with the invention has a commercially acceptable, attractive appearance, is readily shearable to give a smooth shear cut, and corrodes smoothly when subjected to electrochemical corrosion as, for example, in a conventional nickel plating bath.
  • FIG. URE 3 Comparison of the electrolytic nickel pieces depicted in FIGURES 1 and 2 with the electrolytic nickel pieces depicted in FIGURE 3 demonstrates that the nickel produced in accordance with the present invention (FIG- URE 3) is very substantially improved in appearance and shear-ability. All the nickel depicted was produced in a similar fashion but the nickel depicted in FIGURES 1 and 2 contained sulfur at the level of about 0.05%. This material was quite dark in color, was undesirably brittle, as is indicated by the cracking behind the shear cuts, and did not shear to give a smooth shear cut. The commercial acceptability of this material is poor.
  • the nickel depicted in FIGURE 3 at a sulfur level of about 0.02%, is bright and attractive in appearance and shears readily to provide a smooth, clean, shear cut.
  • This mate rial finds ready commercial acceptance on the basis of appearance and its special properties, including the fact that when it is corroded electrochemically in conventional nickel plating baths the corrosion is smooth and uniform and there is essentially no loose nickel with very little sludge resulting from the corrosion.
  • the special electrolytic nickel produced in accordance with the invention has an unusual microstructure, including as characterizing features areas of an apparent dendritic structure presenting a pine tree effect and quite pronounced striae or hands or laminae of a darker-etching appearance.
  • the said bands or striae evidently are islands which appear randomly in the structure.
  • FIGURE 4 in the drawing depicts areas of the darker etching striae and areas of pine tree" effect.
  • the grain size of the special electrolytic nickel is fine.
  • a thin nickel starting sheet was immersed in the electrolyte and current was passed through the electrolyte at a cathode current density of 15 amperes per square foot with the electrolyte temperature being about 140 F.
  • Nickel from the electrolyte was deposited upon both faces of the nickel starting sheet in order to grow a cathode having a total thickness of /2 inch.
  • the resulting cathode contained about 0.02% sulfur and was found to have a bright, smooth appearance.
  • the cathode was sheared into pieces about one inch square and it was found that the material sheared readily to give a smooth cut face. Portions thereof were inserted in a titanium plating basket immersed in a standard Watts-type bath.
  • the cathode nickel material corroded smoothly with essentially no production of metallic nickel and with only a minor proportion of sludge being formed during the corrosion.
  • the cathode material exhibited a negative potential of about 0.1 volt when measured against S.C.E. in an all-sulfate bath.
  • the material exhibited high chemical activity in that about 43% of a test coupon made therefrom dissolved in five hours exposure without agitation to an aqueous solution (1 :1 ratio) of nitric acid (70.2% HNO by weight) whereas under similar conditions only 17% of a similar test coupon made of conventional electrolytic nickel was dissolved.
  • Satisfactory aqueous electrolytes which may be employed in the electrorefining operation in accordance with the present invention have compositions as set forth in the following table.
  • sulfur dioxide is the advantageous ingredient employed in the electrolyte for the purpose of introducing sulfur into the special cathode nickel provided in accordance with the invention.
  • the sulfur dioxide content of the electrolyte can be removed completely merely by aerating the electrolyte which may thereupon be employed for the purpose of producing electrolytic nickel essentially devoid of sulfur.
  • the sulfur content of the special cathode nickel produced produced in accordance with the invention can be replaced wholly or partly by at least one element from the group consisting of selenium, tellurium and phosphorus. When such agents are employed they may be introduced into the electrolyte in the form of compounds which do not contain metallic cations.
  • selenium may, advantageously, be introduced into the electrolyte in the form of selenous acid in the amount of about 0.007 to about 0.08 gram per liter to introduce about 0.01% to about 0.2% of selenium into the cathode nickel.
  • Tellurium may be introduced into the electrolyte in the form of tellurium dioxide in the amount of 0.005 to 0.06 gram per liter to introduce about 0.01% to about 0.1% of tellurium into the cathode nickel and phosphorus may be introduced into the electrolyte in the form of hypophosphorus acid in the amount of about 0.01 to about 1.5 grams per liter to introduce about 0.02% to about 3% of phosphorus into the cathode nickel.
  • cathode nickel having increased chemical and electrochemical activity is useful in many industrial applications, including electroplating, the production of nickel salts, etc.
  • electrolytic nickel having in the as-deposited condition improved electrochemical activity and corrodability along with a highly satisfactory appearance and good shearing characteristics in a commercial scale refinery under controllable conditions is achieved by incorporating in the electrolyte a special combination of special amounts of ingredients, including sulfur dioxide and an agent such as hydracrylonitrile.
  • a special combination of special amounts of ingredients including sulfur dioxide and an agent such as hydracrylonitrile.
  • the structure of electrodeposited metals is unique due to the conditions under which the deposit is formed.
  • electrolytically deposited metals can offer a variety of structures. Such metals usually are stressed, have dislocations in the structure and, at times, may demonstrate crystalline formations which are similar to dendrites formed from molten metals.
  • the improvement for producing electrolytic nickel having a high combination of chemical and physical properties, including electrochemical activity, shearability, and good surface appearance which comprises establishing an aqueous acid nickel electrorefining electrolyte having dissolved therein about 0.01 to about 0.02 gram per liter of sulfur dioxide and about 25 to about 75 milligrams per liter of hydracrylonitrile, immersing a cathode therein, and passing current at a cathode current density of about 5 to about 25 amperes per square foot through said electrolyte to said cathode while maintaining the temperature of said electrolyte between about F. and about F. to deposit electrolytic nickel containing sulfur in a controlled amount of about 0.01% to about 0.02% distributed therethrough.
  • the improvement for producing electrolytic nickel having a high combination of chemical and physical properties, including electrochemical activity, shearability, and good surface appearance which comprises establishing an aqueous acid electrorefining electrolyte having dissolved therein at least one agent from the group consisting of about 0.005 to about 0.025 gram per liter of sulfur dioxide, about 0.007 to about 0.08 gram per liter of selenous acid, about 0.005 to about 0.06 gram per liter of tellurium dioxide, and about 0.01 to about 1.5 grams per liter of hypophosphorous acid, and about 25 to about 75 mill-igrams per liter of at least one agent from the group consisting of hydracrylonitrile, acetonitrile, acrylonitrile, acetaldehyde cyanohydrin, cyanoacetic acid, acetone cyanohydrin, propionitrile, Z-cyanoacetarnide, beta-chloropropionitrile, benz
  • electrolytic cathode nickel containing at least one agent from the group consisting of about 0.005% to about 0.025% sulfur, about 0.01% to about 0.2% selenium, about 0.01% to about 0.1% tellurium, and about 0.02% to about 3% phosphorus distributed therethrough.
  • electrolytic nickel containing about 0.01% to about 0.02% sulfur distributed therethrough and characterized in the as-deposited condition by high electrochemical activity, including a negative potential on the order of about minus 0.1 volt as measured against a standard calomel electrode up to an anod-ic current density of about 150 amperes per square foot in an aqueous electrolyte consisting essentially of about grams per liter of nickel sulfate, about grams per liter of sulfate ion, a pH of about 4- and a temperature of about F., by good surface appearance and shearability in sections at least three-eighths inch thick, and the ability to corrode smoothly when subjected to electrochemical corrosion and by a microstructure including readily-etched, fine-grained striations.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)
  • Electroplating And Plating Baths Therefor (AREA)
US383888A 1964-07-20 1964-07-20 Production of electrolytic nickel Expired - Lifetime US3437571A (en)

Priority Applications (10)

Application Number Priority Date Filing Date Title
US383888A US3437571A (en) 1964-07-20 1964-07-20 Production of electrolytic nickel
SE00523/65A SE327562B (fr) 1964-07-20 1965-01-15
FI650123A FI45995C (fi) 1964-07-20 1965-01-20 Epäpuhtaan nikkeliaineksen elektrolyyttinen raffinointimenetelmä.
NL6500944A NL6500944A (fr) 1964-07-20 1965-01-26
FR4692A FR1432652A (fr) 1964-07-20 1965-02-08 Procédé d'affinage électrolytique du nickel et nickel affiné en résultant
BE659469D BE659469A (fr) 1964-07-20 1965-02-09
AT127465A AT257963B (de) 1964-07-20 1965-02-12 Verfahren zur Elektroraffination eines unreinen Nickelmaterials
ES0309323A ES309323A1 (es) 1964-07-20 1965-02-13 Un metodo para refinar electroliticamente material de niquel impuro.
DEJ27517A DE1234999B (de) 1964-07-20 1965-02-15 Verfahren zur Herstellung von Elektrolytnickel
GB30786/65A GB1056087A (en) 1964-07-20 1965-07-20 Production of electrolytic nickel

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US383888A US3437571A (en) 1964-07-20 1964-07-20 Production of electrolytic nickel

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US3437571A true US3437571A (en) 1969-04-08

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US (1) US3437571A (fr)
AT (1) AT257963B (fr)
BE (1) BE659469A (fr)
DE (1) DE1234999B (fr)
ES (1) ES309323A1 (fr)
FI (1) FI45995C (fr)
FR (1) FR1432652A (fr)
GB (1) GB1056087A (fr)
NL (1) NL6500944A (fr)
SE (1) SE327562B (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU589009B2 (en) * 1986-05-27 1989-09-28 Anglo American Corporation Of South Africa Limited An apparatus and a method for separating one solid component from another solid component in suspension in a liquid
US20060016692A1 (en) * 2002-11-27 2006-01-26 Technic, Inc. Reduction of surface oxidation during electroplating
US8329336B2 (en) 2010-09-29 2012-12-11 General Electric Company Composition and energy storage device

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3715286A (en) * 1971-03-11 1973-02-06 Int Nickel Co Electrorefined nickel of controlled size

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2125229A (en) * 1936-04-14 1938-07-26 Harshaw Chem Corp Electrodeposition of metals
GB525848A (en) * 1939-03-02 1940-09-05 Udylite Corp Improvements in or relating to the electro-deposition of nickel
US2392708A (en) * 1941-06-13 1946-01-08 Int Nickel Co Method of making sulphur-containing nickel anodes electrolytically
US2524010A (en) * 1946-07-12 1950-09-26 Harshaw Chem Corp Electrodeposition of nickel
US2623848A (en) * 1943-06-12 1952-12-30 Int Nickel Co Process for producing modified electronickel
US2635076A (en) * 1947-01-29 1953-04-14 Harshaw Chem Corp Bright nickel plating
US3090733A (en) * 1961-04-17 1963-05-21 Udylite Res Corp Composite nickel electroplate
US3114687A (en) * 1961-03-10 1963-12-17 Int Nickel Co Electrorefining nickel

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2453757A (en) * 1943-06-12 1948-11-16 Int Nickel Co Process for producing modified electronickel

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2125229A (en) * 1936-04-14 1938-07-26 Harshaw Chem Corp Electrodeposition of metals
GB525848A (en) * 1939-03-02 1940-09-05 Udylite Corp Improvements in or relating to the electro-deposition of nickel
US2392708A (en) * 1941-06-13 1946-01-08 Int Nickel Co Method of making sulphur-containing nickel anodes electrolytically
US2623848A (en) * 1943-06-12 1952-12-30 Int Nickel Co Process for producing modified electronickel
US2524010A (en) * 1946-07-12 1950-09-26 Harshaw Chem Corp Electrodeposition of nickel
US2635076A (en) * 1947-01-29 1953-04-14 Harshaw Chem Corp Bright nickel plating
US3114687A (en) * 1961-03-10 1963-12-17 Int Nickel Co Electrorefining nickel
US3090733A (en) * 1961-04-17 1963-05-21 Udylite Res Corp Composite nickel electroplate

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU589009B2 (en) * 1986-05-27 1989-09-28 Anglo American Corporation Of South Africa Limited An apparatus and a method for separating one solid component from another solid component in suspension in a liquid
US20060016692A1 (en) * 2002-11-27 2006-01-26 Technic, Inc. Reduction of surface oxidation during electroplating
US8329336B2 (en) 2010-09-29 2012-12-11 General Electric Company Composition and energy storage device

Also Published As

Publication number Publication date
ES309323A1 (es) 1965-12-16
FI45995B (fr) 1972-07-31
AT257963B (de) 1967-11-10
BE659469A (fr) 1965-08-09
GB1056087A (en) 1967-01-25
NL6500944A (fr) 1966-01-21
SE327562B (fr) 1970-08-24
DE1234999B (de) 1967-02-23
FR1432652A (fr) 1966-03-25
FI45995C (fi) 1972-11-10

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