US3661732A - Method and apparatus for electroplating - Google Patents

Method and apparatus for electroplating Download PDF

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Publication number
US3661732A
US3661732A US42435A US3661732DA US3661732A US 3661732 A US3661732 A US 3661732A US 42435 A US42435 A US 42435A US 3661732D A US3661732D A US 3661732DA US 3661732 A US3661732 A US 3661732A
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Prior art keywords
solution
liquid
electroplating
fumes
water
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US42435A
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English (en)
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David A Withrow
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Production Machinery Corp
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Production Machinery Corp
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    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25D—PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTION OF COATINGS; ELECTROFORMING; APPARATUS THEREFOR
    • C25D21/00—Processes for servicing or operating cells for electrolytic coating
    • C25D21/16—Regeneration of process solutions
    • C25D21/18—Regeneration of process solutions of electrolytes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S204/00—Chemistry: electrical and wave energy
    • Y10S204/13—Purification and treatment of electroplating baths and plating wastes

Definitions

  • the process is preferably conducted in apparatus UNITED STATES PATENTS comprising an electroplating tank, a rinse tank, a fume exhaust system, a heat exchanger and a liquid-vapor contacting 3,485,743 12/1969 Mayland et al. ..204/234 mean5 857,927 6/1907 Dow et a] ...204/233 X 1,012,809 12/1911 Bull ..204/233 X 31 Claims, 1 Drawing Figure i EMERGING A BLOWER 4 m DRYERS 49 ⁇ NX -T INLET 26 f it. I 3 -25 CONCENTRATOR I5 "52,,
  • Electroplating from aqueous solutions is accomplished, generally speaking, by passing an electric current through an electroplating bath solution todeposit the plating material on the workpiece.
  • an electric current In order to control the quality of the plated product, it is often necessary to maintain the temperature of the bath within a narrow temperature range, generally at somewhat elevated temperatures. The passage of electric current through the bath, however, tends to raise the bath temperature and to generate fumes from it.
  • the electroplating reaction usually forms gases at the electrodes. For example, in the electroplating of chromium from a chromic acid solution, large volumes of hydrogen and oxygen are given off. These gases bubble up through the bath and a spray of the plating solution is produced.
  • an endless strip is introduced into and removed from the electroplating bath by means of rollers which conduct the strip through the bath and through any required rinse baths.
  • the splashing which results from the workpiece entering and leaving the electroplating bath also tends to form a spray of the bath solution.
  • the invention further contemplates providing an apparatus for recovering values contained in fumes emanating from the electroplating operations.
  • Still another object of the invention is to provide an apparatus for recovering chemical values from rinse water which values were carried over from the electroplating operation.
  • the present invention contemplates a process for recovering values contained in fumes emanating from electroplating operations including rinsing operations, while simultaneously controlling the temperature and water balance of the electroplating bath.
  • the process comprises contacting the fumes with at least a portion of the process solution to dissolve therein values contained in the fumes and to evaporate water therefrom.
  • process solution as used herein includes, but is not necessarily limited to, the electroplating bath solution and/or the rinse water.
  • the process solution after being contacted with the fumes and having given up water to the fumes and absorbed values therefrom, is added to the electroplating solution.
  • Steel strip 12 is guided into and out of individual rinsing compartments 20 by rolls 23 and is wiped by rolls 24 upon emerging from each of the rinsing stages.
  • plated steel strip 12 passes through the last pair of wiping rolls 24 and is then sprayed with fresh water issuing from spray nozzles 25.
  • the plated steel strip, after being sprayed with fresh water from nozzles 25, is then wiped with final wiping rolls 26 before being conveyed through passage 27 out of gas hood D and then through dryers 28. After drying, the strip can be coiled or treated in any other appropriate manner.
  • Plating solution from electroplating tank A and overflow rinse water from rinse tank B are passed through conduits 31 and 32, respectively, to conduit 33 which conveys the combined solutions to the concentrator C.
  • the FIGURE shows the solutions'from plating tank A flowing by gravity via overflow pipes 31a, 31b, 31c, and 31d through conduit 31.
  • the solution from rinsing tank B is shown flowing by gravity through conduit 32.
  • the solutions are admixed in conduit '33 and then flow by gravity into the concentrator C.
  • the FIGURE shows rinse water passing through a cation exchanger 34 before being combined with electroplating solution from tank A.
  • the cation exchange process and the desirability of providing the same will be described in greater detail hereinafter in conjunction with the more detailed description of the process.
  • Concentrator C may be any suitable means for effecting intimate liquid-vapor contact between the fumes obtained from tanks A and B and the process solution.
  • concentrator C is preferably a conventional packed tower that is constructed of any material that is corrosion resistant to the plating solution being treated.
  • the tower can be constructed of stainless steel or titanium or polyvinylchloride or glass lined carbon steel.
  • the concentrator C comprises generally a lower chamber 40 forming a reservoir for combined plating solution and rinse water, a packed bed 41, a second packed bed 42, conduit 43 for passing fumes collected by gas hood D into packed bed 41, damper 44 for controlling the flow of supplemental air into packed bed 41, blower 45 for exhausting gases that have passed through packed bed 41 and packed bed 42, pump 46 for conveying solution from reservoir 40 to packed bed 41 and means 47 for distributing the solution uniformly over the bed.
  • the lower chamber 40 can be constructed of any suitable material, such as carbon or graphite blocks or any other material which is resistant to chemical attack by the plating solution.
  • the electrolyte solution in reservoir 40 is circulated by pump 52 to tank A to replace the solution withdrawn from tank A via conduit 31.
  • An independent-flow loop provides circulation through concentrator C of the solution from reservoir 40, by means of pump 46, thence through heat exchanger 54 to distributors 47, which distribute the solution over the surface of packed bed 41.
  • the solution trickles through packed bed 41 wherein it comes into intimate gas-liquid contact with the fumes (and supplemental air) passing upwardly through packed bed 41.
  • An amount of water, controlled as hereinbefore described, is evaporated from the solution which is thereby concentrated to the desired degree and cooled while chemical values in the gas stream condense into the downwardly flowing solution.
  • the electroplating solution is cooled by giving up heat of vaporization to the water evaporating in the concentrator in a single operation which simultaneously controls the water balance of the electroplating solution, recovers values from and purifies the fumes generated by the electroplating process and recycles, rather than discharging to waste, rinse water contaminated by the electroplating solution.
  • the total amount of gases and fumes collected from the electroplating operation is supplemented by sufficient air to evaporate the required amount of water.
  • the temperature of the electroplating bath can be controlled by adding thereto, controlled amounts of the cooled solution obtained from the gas-liquid contacting step, e.g., from reservoir 40, and if necessary, passing the cooled solution in heat exchange, e.g., in heat exchanger 54 in the FIGURE, to further cool or to warm the solution as may be required in a specific case.
  • the plating solution is constantly being depleted of plating values, e.g., chromic acid, due to the plating reaction; additional reagents along with other necessary or useful constituents can be added to the system at any convenient point.
  • a convenient point for additions would be to the solution contained in reservoir 40.
  • catalytic acid radicals are needed in the electroplating tank A to insure constant and soluble plating conditions.
  • sulphate ions may be employed in amount sufficient to maintain a chromate (CrO to sulphate (S0 ratio of between about 50:1 and 250:1.
  • a standard ba contains about 250 grams per liter (gpl) C10 and 2.5 gpl 80,.
  • a silicofluoride type catalyst may be added to a standard bath in excess amounts to provide a self-regulating bath since silicofluoride catalysts display only limited solubilities and the required amount dissolves only as needed.
  • hydrofluoric acid is added in amounts to provide a chromic acid to fluoride ratio between about 50:1 and 250:1.
  • the plated steel strip passes to rinsing tank B and electroplating solution clinging thereto is rinsed from the strip.
  • the rinsing operation is advantageously conducted on a countercurrent basis to provide more efficient rinsing and to provide an overflow rinse solution which is relatively concentrated in values carried over by the steel strip.
  • liquidliquid techniques are also effective in lowering the trivalent chromium content.
  • An example of a liquid ion exchanger is diononylnaphthalene sulfonic acid dissolved in heptane.
  • Plating solution at a rate of 2,000 gallons per minute is combined with the overflow rinse water to provide a solution at a temperature of about 1 13 F.
  • the combined solution is transferred to the reservoir of a packed tower, which reservoir contains 10,000 gallons of solution at a temperature of 1 10 F.
  • a packed bed is sprayed with 2,000 gallons per minute of solution from reservoir 40 at a temperature of 125 F., while 35,000 standard cubic feet per minute of fume exhaust collected by gas hoods D are drawn through the packed bed along with 30,000 standard cubic feet per minute additional air by blower 45. Gases after passing through packed bed 42 to collect any mist generated in packed bed 41 or in the operation thereof are exhausted to the atmosphere at a temperature of 125 F.
  • the process of claim 2 further including carrying out the intimate liquid-vapor contact in a packed bed of large surface area elements adapted to facilitate liquid-vapor contact and wherein the process solution is sprayed upon the upper sur face of the packed bed and passes downwardly therethrough and the fumes are passed upwardly through the packed bed to provide countercurrent contact between the process solution and the fumes whereby values contained in the fumes are dissolved into the process solution and is evaporated from the process solution whereby the process solution is cooled.
  • the plating solution is an aqueous chromic acid solution for electroplating chromium.
  • the process of claim 9 further including a rinsing step in which the plated article is rinsed with rinse water upon emerging from the electroplating tank and wherein all of the used rinse water and at least a portion of the aqueous chromic acid solution are contacted with the cation exchange resin.
  • conduit means for conducting contacted liquid from said liquid-vapor contacting means into said electroplating tank.
  • the combination of claim 23 further including a tower in which said packed bed and said demisting means are placed with the demisting means being the uppermost, a lower chamber in said tower forming a reservoir for collecting liquid passing through the packed bed and for providing solution to be sprayed onto the packed bed and means for pumping liquid in said reservoir to the packed bed.

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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)
  • Electroplating Methods And Accessories (AREA)
US42435A 1970-06-01 1970-06-01 Method and apparatus for electroplating Expired - Lifetime US3661732A (en)

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US4243570A 1970-06-01 1970-06-01

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US (1) US3661732A (fr)
JP (1) JPS558599B1 (fr)
BE (1) BE762293A (fr)
CA (1) CA923068A (fr)
DE (1) DE2124864B2 (fr)
FR (1) FR2093929B1 (fr)
GB (1) GB1320645A (fr)

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3903237A (en) * 1973-06-04 1975-09-02 Nat Steel Corp Recovering hexavalent chromium for reuse
US3950216A (en) * 1974-01-18 1976-04-13 The United States Of America As Represented By The United States Energy Research And Development Administration Falling film evaporator
US3985628A (en) * 1975-08-04 1976-10-12 Myers Lyle R Pollution control in electroplating systems
US4157942A (en) * 1976-03-08 1979-06-12 Instytut Mechaniki Precyzyjnej Method for recovery of metals from metal plating baths and neutralizing toxic effluents therefrom
US4163705A (en) * 1975-05-06 1979-08-07 Korpi Teuvo Tapio Apparatus for chemical and electrochemical treatment
US4171255A (en) * 1977-02-18 1979-10-16 Instytut Mechaniki Precyzyjnes Apparatus for recovery of metals from metal plating baths and neutralizing toxic effluents therefrom
US4340451A (en) * 1979-12-17 1982-07-20 Bell Telephone Laboratories, Incorporated Method of replenishing gold/in plating baths
US4409064A (en) * 1978-10-16 1983-10-11 Air Products And Chemicals, Inc. Process for concentrating sulfuric acid in an evaporator
US4592819A (en) * 1981-03-03 1986-06-03 Yamaha Hatsudoki Kabushiki Kaisha Electroplating apparatus with ventilation means
GB2182058A (en) * 1985-10-11 1987-05-07 Dominic Tenace Treating effluent from electroplating plant or metal stripping plant
US4781806A (en) * 1985-10-11 1988-11-01 Dominic Tenace Electroplating system
US5269905A (en) * 1990-04-30 1993-12-14 Elf Atochem North America, Inc. Apparatus and process to regenerate a trivalent chromium bath
US5401379A (en) * 1993-03-19 1995-03-28 Mazzochi; James L. Chrome plating process
EP0781864A1 (fr) * 1995-12-15 1997-07-02 Nichiei Hard Chrome Industrial Company Solution pour le dépÔt de chrome, solution residuelle du dépÔt de chrome et système de recyclage des eaux de nettoyage de l'acide chromique dans un procédé de chromage
US20050022728A1 (en) * 2001-10-03 2005-02-03 C. G. Therkildsen Apparatus for improving corrosion resistance of chrome plated material
US20050123683A1 (en) * 2001-10-03 2005-06-09 C.G. Thirkeldsen Method and apparatus for improving corrosion resistance of chrome plated material
US20060151330A1 (en) * 2002-11-27 2006-07-13 Christophe Mathieu Device for the metallisation of printed forms which are equipped with electrically conductive tracks and associated metallisation method
WO2009012891A1 (fr) * 2007-07-25 2009-01-29 A.C.K. Aqua Concept Gmbh Karlsruhe Recyclage de bains galvaniques
US20090272644A1 (en) * 2008-04-30 2009-11-05 Alcatel Lucent Plating apparatus with direct electrolyte distribution system
CN110965114A (zh) * 2018-09-29 2020-04-07 上海梅山钢铁股份有限公司 一种甲基磺酸锡系电镀液的回收装置及方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2426098A1 (fr) * 1978-05-17 1979-12-14 Zindel Laurent Procede et installation de traitement d'articles dans un bain contenant des produits de traitement polluants, en particulier de traitement de zincage
DE2914722C2 (de) * 1979-04-11 1982-05-27 Langbein-Pfanhauser Werke Ag, 4040 Neuss Anlage für die galvanotechnische Behandlung von Gegenständen

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US857927A (en) * 1906-04-18 1907-06-25 Ontario Nickel Company Ltd Process of recovering the nickel contained in basic nickel precipitates.
US1012809A (en) * 1911-05-10 1911-12-26 Chloride Process Company Apparatus for purifying water.
US3485743A (en) * 1967-07-21 1969-12-23 Girdler Corp Apparatus for removal of acidic gases from gaseous atmospheres

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE485185A (fr) * 1942-02-27
US2430750A (en) * 1944-07-18 1947-11-11 United Chromium Inc Method of electroplating to produce fissure network chromium plating
FR1395008A (fr) * 1964-02-28 1965-04-09 Cuve de traitement, notamment pour le chromage électrolytique
US3616304A (en) * 1966-01-26 1971-10-26 M & T Chemicals Inc Method for treating chromium-containing baths
BE683946A (fr) * 1966-07-11 1966-12-16

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US857927A (en) * 1906-04-18 1907-06-25 Ontario Nickel Company Ltd Process of recovering the nickel contained in basic nickel precipitates.
US1012809A (en) * 1911-05-10 1911-12-26 Chloride Process Company Apparatus for purifying water.
US3485743A (en) * 1967-07-21 1969-12-23 Girdler Corp Apparatus for removal of acidic gases from gaseous atmospheres

Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3903237A (en) * 1973-06-04 1975-09-02 Nat Steel Corp Recovering hexavalent chromium for reuse
US3950216A (en) * 1974-01-18 1976-04-13 The United States Of America As Represented By The United States Energy Research And Development Administration Falling film evaporator
US4163705A (en) * 1975-05-06 1979-08-07 Korpi Teuvo Tapio Apparatus for chemical and electrochemical treatment
US3985628A (en) * 1975-08-04 1976-10-12 Myers Lyle R Pollution control in electroplating systems
US4157942A (en) * 1976-03-08 1979-06-12 Instytut Mechaniki Precyzyjnej Method for recovery of metals from metal plating baths and neutralizing toxic effluents therefrom
US4171255A (en) * 1977-02-18 1979-10-16 Instytut Mechaniki Precyzyjnes Apparatus for recovery of metals from metal plating baths and neutralizing toxic effluents therefrom
US4409064A (en) * 1978-10-16 1983-10-11 Air Products And Chemicals, Inc. Process for concentrating sulfuric acid in an evaporator
US4340451A (en) * 1979-12-17 1982-07-20 Bell Telephone Laboratories, Incorporated Method of replenishing gold/in plating baths
US4592819A (en) * 1981-03-03 1986-06-03 Yamaha Hatsudoki Kabushiki Kaisha Electroplating apparatus with ventilation means
GB2182058A (en) * 1985-10-11 1987-05-07 Dominic Tenace Treating effluent from electroplating plant or metal stripping plant
US4781806A (en) * 1985-10-11 1988-11-01 Dominic Tenace Electroplating system
GB2182058B (en) * 1985-10-11 1990-02-21 Dominic Tenace Electroplating system
US5269905A (en) * 1990-04-30 1993-12-14 Elf Atochem North America, Inc. Apparatus and process to regenerate a trivalent chromium bath
USRE35730E (en) * 1990-04-30 1998-02-17 Elf Atochem North America, Inc. Apparatus and process to regenerate a trivalent chromium bath
US5401379A (en) * 1993-03-19 1995-03-28 Mazzochi; James L. Chrome plating process
EP0781864A1 (fr) * 1995-12-15 1997-07-02 Nichiei Hard Chrome Industrial Company Solution pour le dépÔt de chrome, solution residuelle du dépÔt de chrome et système de recyclage des eaux de nettoyage de l'acide chromique dans un procédé de chromage
US5766428A (en) * 1995-12-15 1998-06-16 Nichiei Hard Chrome Industrial Company Chromium plating solution, solution waste from chromium plating and closed recycling system for chromic acid cleaning water in chromium plating
US20100101488A1 (en) * 2001-10-03 2010-04-29 Therkildsen Charles G Method and Apparatus for Improving Corrosion Resistance of Chrome Plated Material
US20050022728A1 (en) * 2001-10-03 2005-02-03 C. G. Therkildsen Apparatus for improving corrosion resistance of chrome plated material
US20050123683A1 (en) * 2001-10-03 2005-06-09 C.G. Thirkeldsen Method and apparatus for improving corrosion resistance of chrome plated material
US7037373B2 (en) 2001-10-03 2006-05-02 Industrial Hard Chrome, Ltd. Apparatus for improving corrosion resistance of chrome plated material
US8303783B2 (en) 2001-10-03 2012-11-06 Industrial Hard Chrome, Ltd. Method and apparatus for improving corrosion resistance of chrome plated material
US7641782B2 (en) 2001-10-03 2010-01-05 Industrial Hard Chrome, Ltd. Method and apparatus for improving corrosion resistance of chrome plated material
US20060151330A1 (en) * 2002-11-27 2006-07-13 Christophe Mathieu Device for the metallisation of printed forms which are equipped with electrically conductive tracks and associated metallisation method
CN101809208B (zh) * 2007-07-25 2012-06-20 A.C.K.阿夸概念卡尔斯鲁厄有限责任公司 电镀浴的再循环过程
WO2009012891A1 (fr) * 2007-07-25 2009-01-29 A.C.K. Aqua Concept Gmbh Karlsruhe Recyclage de bains galvaniques
US20090272644A1 (en) * 2008-04-30 2009-11-05 Alcatel Lucent Plating apparatus with direct electrolyte distribution system
US8366884B2 (en) * 2008-04-30 2013-02-05 Alcatel Lucent Plating apparatus with direct electrolyte distribution system
CN110965114A (zh) * 2018-09-29 2020-04-07 上海梅山钢铁股份有限公司 一种甲基磺酸锡系电镀液的回收装置及方法
CN110965114B (zh) * 2018-09-29 2021-12-14 上海梅山钢铁股份有限公司 一种甲基磺酸锡系电镀液的回收装置及方法

Also Published As

Publication number Publication date
BE762293A (fr) 1971-07-01
FR2093929B1 (fr) 1974-02-15
FR2093929A1 (fr) 1972-02-04
CA923068A (en) 1973-03-20
DE2124864B2 (de) 1974-08-08
DE2124864A1 (de) 1971-12-09
JPS558599B1 (fr) 1980-03-05
GB1320645A (en) 1973-06-20

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