Electrowinning, còn gọi là electroextraction, là điện cực của kim loại từ quặng của chúng đã được đưa vào dung dịch thông qua một quá trình thường được gọi là lọc quặng. Electrorefining sử dụng một quá trình tương tự để loại bỏ các tạp chất từ một kim loại. Cả hai quy trình đều sử dụng mạ điện trên quy mô lớn và là những kỹ thuật quan trọng để lọc tinh khiết và đơn giản các kim loại màu. Các kim loại kết quả được gọi là electrowon
CONTENTS PART L—ELECTRO-PLATING CHAPTER L PRELIMINARY CONSIDERATIONS.—PRIMARY AND SECONDARY BATTERIES PA The Electric Current.—Electricity Moving Force.—The Electric Circuit.—Sources* ot Elcctiieity Moving Force.—Chemical Kiectric Batteries—Magnitudes of E.M.F ot Batteries.—l'olan^ation.— Polurit\ ot Batteries—Primary Batteries—The Lalaude (ell.—The Daniell Cell —Amalgamation of Zincs.—Management of Primary Batteries.—Relative Activity of Primary Cells.—Constancy of Piiinarx CelU—General ltemaikson Primary Batteries.—Secondary Batteues.—Care and Rep in ot becondaiy Batteries.—Annual Cost of Upkeep ot ^ei'ondan Batteries—Electrolytes.—Short Ciicuits.— Connection ot Batteries in Seues and Paiallel.—Ammeters and Voltmeters < CHAPTER II THERMOPILES.—DYNAMOS.—THE COST OF ELECTRICAL INSTALLATIONS OF SMALL OUTPUT FOR ELECTRO-PLATING, ETC The Thermopile.—The Gulcher Thermopile.—The Cox Thermopile.— The Clamond Thermopile.—The Dsnamo —Points to be consideied in Buying a D\namo.—Caie ot Dynamo.—Driving Belts.—Staiting and Stopping a D\namo.—Cost of Small Dynamo**.—Cost of MotorDynamos.—Specih'cations tor and Choice ot Motor-Dvnamos Safety Precautions with Motors of Motor-Dynamos.—Choice of Xll PKEFACE TO FIRST EDITION important details ; and having himself worked most of the operations of the art upon a very extensive scale, he is enabled in many instances to give the results of his own practical experience ELECTHO-METALLURGY, which is now recognised as a distinct branch of electro-chemistry, has been treated separately, and those processes which have been practically adopted, such as the electrolytic refining of crude copper; are exhaustively given, while other processes, now only upon their trial, are described In this section also will be found a description of the new process of electric smelting, as applied, more especially, to the production of aluminium and silicon bronzes In conclusion, the author tenders his best thanks to those who kindly furnished him with information, for the readiness and pi omptitude with which they complied with his requests ALEXANDER WATT LOISDON, December', 1885 CONTENTS XV11 CHAPTER XIV ELECTRO-DEPOSITION OF SILVER PAGE Preparation of Nitrate of Silver.—Observations on Commercial Cyanide.—Preparation of Silver Solutions.—Bright Plating.—Deposition by Simple Immersion.—Whitening Articles by Simple Immersion.—Whitening Brass Clock Dials, &c , 227 CHAPTER XV ELECTRO-DEPOSITION OF SILVER (continued) Preparation of New Work for the Bath.—Quicking Solutions, or Mercury Dips.—Potash Bath.—Acid Dips.—Dipping.—Spoon and Fork Work.—Wiring the Work.—Arrangement of the Plating Bath.— Plating Battery.—Motion given to Articles while in the Bath.— Cruet Stands, &c.—Tea and Coffee Services.—Scratch-Brushing 241 CHAPTER XVL ELECTRO-DEPOSITION OF SILVER (continued) Plating Britannia Metal, ition of Palladium.—Deposition of Bismuth.—Deposition of Antimony.—Deposition of Lead.—Metallo-Chromes.—Deposition of Aluminium.—Deposition of Cadmium.—Deposition of Chromium.— Deposition of Manganium.—Deposition of Magnesium.—Deposition of Silicon 356 # CHAPTER XXIV ELECTRO-DEPOSITION OF ALLOYS Electro-deposition of Brass and Bronze.—Brassing Solutions.—Brunei, Bisson, and Co 's Processes.—DeSalzede's Processes.—Newton's Processes.—Kussell and Woolrich's Process.—Wood's Process.—Morris and Johnson's Process.—Dr Ueeren's Process.—Roseleur's Processes.—Walenn's Processes.—Bacco's Solution.—Winckler's Solution.—American Formulae lor Brassing Solutions.—Thick Brabs Deposits.—Brass Solution prepaied by Battery Process 374 CHAPTER XXV ELECTRO-DEPOSITION OF ALLOYS (continued) Electro-bi assing Cast-iron Work —Scouring.—Electro-bra^singWroughtiron Work.—Electro-bra c sing Zinc Work —Electio-brassing Lee.c\ XV111 CONTENTS CHAPTER XVIII ELECTRO-DEPOSITION OF NICKEL PAGI Application of Nickel-plating.—The Depositing Tank.—Conducting Rods.—Preparation of the Nickel Solution.—Nickel dnodes.— Nickel-plating by Battery.—The Twin-Carbon Battery.—Observations on Preparing Work for Nickel-plating.—The Potish Bath.— Dips, or Steeps.—Dipping Acid.—Pickling Bath 2S8 CHAPTER XIX ELECTRO-DEPOSITION OF NICKEL {continued) Preparation of Nickeling Solutions.—Adams* Process —Unwin's Process — Weston's Process — Powell's Process — Potts' Process.— Double Cyanide of Nickel and Potassium Solution.—Solution for Nickeling Tin, Britannia Metal, &c.—Simple Method of Preparing Nickel baits.—Desmur's Solution for Nickeling Small Articles 299 CHAPTER XX ELECTRO-DEPOSITION OF NICKEL (continued) Prepaiation of the Work for Nickel-plating.—The Scouring Tray.—Brass and Copper Work.—Nickeling small Steel Articles.—Nickeling small Brass and Copper Articles.—Nickeling by Dynamoelectricity.—Nickeling Mullers, Sausage Warmers, &c.—Nickeling Bar Fittings, Sanitary Work,