GB190818596A - Process of Recovering Nickel from Silicious Ores. - Google Patents

Abstract

18,596. Chalas, A. Sept. 6, 1907, [date applied for under Section 91 of Patents &c. Act, 1907]. Nickel, obtaining.-Nickel is recovered from nickel-iron silicate ores, free from copper, by smelting the ore, preferably in an electric furnace, removing the iron as far as possible from the ferro-nickel so obtained, for example, by bessemerizing, and casting the alloy into anodes, from which nickel is deposited on sheet-nickel cathodes immersed in a nickel-ammonium salt solution, preferably the double sulphate. To remove the dissolved iron the electrolyte is continuously circulated through a filter containing a precipitating- agent such as nickelic hydroxide, whereby ferric hydroxide is precipitated and nickel sulphate is dissolved so as to strengthen the electrolyte. The nickelic hydroxide used to precipitate the iron is made by electrolytically dissolving ferro-nickel anodes, such as those obtained in the first part of the process, in an aqueous solution of an alkali salt, for example, sodium chloride, preferably contained in a divided cell, and having cathodes of nickel or iron. The sodium hydroxide solution produced at the cathode is mixed outside the cell with the nickel and iron chlorides formed at the anode, the iron salt being present in small quantity ; nickelous and ferrous hydroxides are precipitated and sodium chloride dissolves and regenerates the electrolyte. The nickelous and ferrous hydroxides are collected in a filter press and converted into nickelic and ferric hydroxides by peroxidation with an alkali hypochloride made by electrolyzing a cold dilute solution of an alkali chloride, and the product is ready for reuse in the process. A set of filters for containing the precipitating- agent may be used to render the process continuous. The precipitated ferric hydroxide which gradually replaces the nickelic hydroxide in the filters may be calcined to colcothar.