Metal primary

Values are minimum for the primary metal and maximum for impurity concentrations. Oxygen-free electrolytic copper containing 0.0001 wt % Bi and Cd and 0.00005 wt % Mn. 

AH metals come originally from natural deposits present in the earth s cmst. These ore deposits result from a geological concentration process, and consist mainly of metallic oxides and sulfides from which metals can be extracted. Seawater and brines are another natural source of metals, eg, magnesium (see Chemicals frombrine Magnesium and magnesium alloys Ocean raw materials). Metal extracted from a natural source is called primary metal. 

Table 1 gives the average metal content of the earth s cmst, ore deposits, and concentrates. With the exceptions of the recovery of magnesium from seawater and alkaU metals from brines, and the solution mining and dump or heap leaching of some copper, gold, and uranium (see Uranium and uranium compounds), most ores are processed through mills. Concentrates are the raw materials for the extraction of primary metals. 

The first equation is an example of hydrolysis and is commonly referred to as chemical precipitation. The separation is effective because of the differences in solubiUty products of the copper(II) and iron(III) hydroxides. The second equation is known as reductive precipitation and is an example of an electrochemical reaction. The use of more electropositive metals to effect reductive precipitation is known as cementation. Precipitation is used to separate impurities from a metal in solution such as iron from copper (eq. 1), or it can be used to remove the primary metal, copper, from solution (eq. 2). Precipitation is commonly practiced for the separation of small quantities of metals from large volumes of water, such as from industrial waste processes. 

AHoy scrap containing tin is handled by secondary smelters as part of their production of primary metals and alloys lead refineries accept solder, tin drosses, babbitt, and type metal. This type of scrap is remelted, impurities such as iron, copper, antimony, and zinc are removed, and the scrap is returned to the market as binary or ternary alloy. The dross obtained by cleaning up the scrap metal is returned to the primary refining process. 

Producers of primary metal and oxide in the United States are Amspec Chemical Corp., Anzon America, ASARCO Inc., Laurel Industries Inc., Sunshine Mining Co., and U.S. Antimony Corp. 

Menstruum Carburization. Mineral concentrates, ferroalloys, primary metals, or high, purity scrap may also be carburized (14). 

If the product is essentially identical to that produced by other manufacturers, then the price is determined principally by the commodity market price. However, contract features such as guaranteed deHvery schedules can influence price. Examples of commodity pricing are petrochemicals, petroleum feedstocks, petroleum products, and primary metals. 

Table 1 is an estimate of energy usage by United States industry for 1988 (1). The chemical industry used 21% of the energy consumed by the U.S. industrial sector, and the other three related process industries, paper (qv), petroleum (qv), and primary metals, combined for an additional 50% of the industrial consumption. 

Energy source Chemicals Petroleum refining Paper Primary metals Other... 

Carhon monoxide Fuming of metallic oxides, gas-operated fork trucks Primary metals steel and aluminum Reduction in oxygen-carrying capacity of blood... 

Hydrogen cyanide From metal plating, blast furnaces, dyestuff works Metal fabricating, primary metals, textiles Capable of affecting nerve cells... 

Hydrogen fluoride Catalyst in some petroleum refining, etching glass, silicate extraction by-product in electrolytic production of aluminum Petroleum, primary metals, aluminum Strong irritant and corrosive action on all body tissue damage to citrus plants, effect on teeth and bones of cattle from eating plants... 

Sulfur dioxide Fuel combustion (coal, oil), smelting and casting, manufacture of paper by sulfite process Primary metals (ferrous and nonferrous) pulp and paper Sensory and respiratory irritation, vegetation damage, corrosion, possible adverse effect on health... 

Table 10.8 outlines the quality requirements of the basis, or primary, metal for the three generic types of anode. These are the qualities required even when sequestering is also adopted. It will be seen that two grades are listed in the case of aluminium. This is because certain patented formulations permit the lower (99- 8%) grade material providing that the iron and silicon are within the limit given. 

It functions as a monoprotic acid (pKa = 4.7) up to a pH of about 12 the acid proton is that of the thiol group in (C). Primary metal dithizonates are formed according to the reaction ... 

This paper will be concerned only with work on the thermodynamic properties of primary metallic solutions, i.e., those which... 

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