"The leaching process for the extraction of silver are comparatively modern, being introduced in 1849. They belong to a period in which the metallurgist has brought to his aid knowledge derived from chemical research. Under favorable circumstances leaching procedures process many advantages over amalgamation or smelting. For successful use the ores treated for silver must not contain large per cents of lead, zinc, antimony or arsenic. The objections to these bodies will be named later on. When silver is extracted by smelting or amalgamation, a costly plant is necessary, which requires constant repair and in time wear out and be replaced, while on the other hand a plant for leaching is cheap. The roasting furnaces need not be of a very expensive type, the leaching tubs, being made of wood, are cheap and for the most part, low priced labor. The reagents used made be used again and again, as the loss is very small. These processes have one disadvantage, they must be constantly watched by an expert and continual assays must be made to see that there is no loss of silver. The reactions are soon learned by the workers.
Leaching process may be divided into two classes; (1) Converting silver to chloride and dissolving (2) Converting the silver to a salt soluable in water. Under the first class fall Augustin process and Van Patera’s process. Augustin converts the silver to chloride then leaches out the silver, chloride by a hot and strong solution of common salt. Van Patera leaches out the silver, chloride by hyposulphite of soda. Under the second class falls Ziervogel’s process. In this process the silver is converted to silver sulphate and water is used for leaching.
On account of lead, antimony, and arsenic being frequently associated with silver, ores, wet methods are not extensively used and in most cases (when used) are applied to extraction of silver from a matt."
Mining and Nuclear Engineering
Professional Degree in Mining Engineering
Missouri School of Mines and Metallurgy
© 1885 Phil VanFrank, All rights reserved.
Thesis - Open Access
Library of Congress Subject Headings
Silver -- Metallurgy
Print OCLC #
Electronic OCLC #
Link to Catalog Record
Van Frank, Phil, "Leaching processes for silver extraction" (1885). Professional Degree Theses. 336.