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Cementation is a type of precipitation, a heterogeneous process in which ions are reduced to zero valence at a solid metallic interface. The process is often used to refine leach solutions. Cementation of copper is a common example. Copper ions in solution, often from an ore leaching process, are precipitated out of solution in the presence of ...
Precipitation is the selective removal of a compound of the targeted metal or removal of a major impurity by precipitation of one of its compounds. Copper is precipitated as its sulfide as a means to purify nickel leachates. Cementation is the conversion of the metal ion to the metal by a redox reaction. A typical application involves addition ...
The gold precipitate (mixed with zinc dust) is then filtered out of the solution, and the zinc dust and gold are mixed with sulfuric acid to dissolve the zinc. The solution is filtered, and the remaining solids are smelted to a gold dore bar. These bars are sent to a refinery to remove the copper and silver, the specific process used depending ...
Precipitation hardening, also called age hardening or particle hardening, is a heat treatment technique used to increase the yield strength of malleable materials, including most structural alloys of aluminium, magnesium, nickel, titanium, and some steels, stainless steels, and duplex stainless steel.
The purest copper is obtained by an electrolytic process, undertaken using a slab of impure copper as the anode and a thin sheet of pure copper as the cathode. The electrolyte is an acidic solution of copper (II) sulfate. By passing electricity through the cell, copper is dissolved from the anode and deposited on the cathode. However ...
16th century cupellation furnaces (per Agricola). Cupellation is a refining process in metallurgy in which ores or alloyed metals are treated under very high temperatures and subjected to controlled operations to separate noble metals, like gold and silver, from base metals, like lead, copper, zinc, arsenic, antimony, or bismuth, present in the ore.
Gravimetric analysis describes a set of methods used in analytical chemistry for the quantitative determination of an analyte (the ion being analyzed) based on its mass. The principle of this type of analysis is that once an ion's mass has been determined as a unique compound, that known measurement can then be used to determine the same analyte's mass in a mixture, as long as the relative ...
The Kirkendall effect is the motion of the interface between two metals that occurs due to the difference in diffusion rates of the metal atoms. The effect can be observed, for example, by placing insoluble markers at the interface between a pure metal and an alloy containing that metal, and heating to a temperature where atomic diffusion is reasonable for the given timescale; the boundary ...