Sulfur/sulfide-oxidizing copper

Furthermore, sulfur combines with copper rather than with iron. Hence, copper sulfide remains ia the converter after the iron has been oxidized and has combiaed with siUca to be skimmed off as a slag. Typical converting reactions of iron sulfide are equations 11, 14, and 15. 

Copper(I) sulfide combines with oxygen to yield copper(I) oxide [1317-39-17, CU2O, and sulfur dioxide. Copper(I) sulfide and copper(I) oxide react to form metallic copper and gaseous sulfur dioxide ia the converters. 

An alternative procedure for removing an ion from solution is to change its identity by changing its oxidation state. The metal ions in very insoluble heavy metal sulfide precipitates can be dissolved by oxidizing the sulfide ion to elemental sulfur. For example, copper(II) sulfide, CuS, takes part in the equilibrium... 

Arbiter Previously known as the Sherritt-Gordon ammonia process. A process for leaching copper from sulfide concentrates, using ammoniacal ammonium sulfate solution at 85°C and relying on air oxidation. Copper is produced from the leachate by solvent extraction and electrowinning. Sulfur is recovered as ammonium sulfate. Operated on a large scale by the Anaconda Copper Company in Montana from 1974 to 1979. See Sherritt-Gordan. 

When heated in air, copper(l) sulfide oxidizes forming copper(ll) oxide, and sulfur dioxide ... 

The lithosphere consists primarily of rocks and minerals. Some of the important classes of metal compounds found in the lithosphere are oxides, sulfides, silicates, phosphates, and carbonates. The atmosphere surrounding the earth contains oxygen, so several metals such as iron, aluminum, tin, magnesium, and chromium are found in nature as the oxides. Sulfur is found in many places in the earth s crust (particularly in regions where there is volcanic activity), so some metals are found combined with sulfur as metal sulfides. Metals found as sulfides include copper, silver, nickel, mercury, zinc, and lead. A few metals, especially sodium, potassium, and magnesium, are found as the chlorides. Several carbonates and phosphates occur in the lithosphere, and calcium carbonate and calcium phosphate are particularly important minerals. 

Iron-chromium oxide catalysts, reduced with hydrogen-containing in the conversion plants, permit reactions temperatures of 350 to 380°C (high temperature conversion), the carbon monoxide content in the reaction gas is thereby reduced to ca. 3 to 4% by volume. Since, these catalysts are sensitive to impurities, cobalt- and molybdenum-(sulfide)-containing catalysts are used for gas mixtures with high sulfur contents. With copper oxide/zinc oxide catalysts the reaction proceeds at 200 to 250°C (low temperature conversion) and carbon monoxide contents of below 0.3% by volume are attained. This catalyst, in contrast to the iron oxide/chromium oxide high temperature conversion catalyst, is, however, very sensitive to sulfur compounds, which must be present in concentrations of less than 0.1 ppm. 

Oxidation of sulfur compounds. The copper(lI) nitrate complexed with dimerizes thiols to afford disulfides and oxidizes sulfides to sulfoxides. 

Copper is easily extracted with 5% sulfuric acid from the ores containing cupric hydroxide, cupric carbonate, and cupric oxide such as azurite, malachite, and teno-rite. However, copper is seldom extracted with sulfuric acid from copper ores containing cupric sulfides the presence of ferric ion is mandatory to extract copper with sulfuric acid from the ores, e.g., chalcopyrite [FeCuS2]. 

Determined sulfur tolerance of copper (Cu)/mixed oxide catalyst catalyst loses all WGS activity after 45 hours on 4.5 ppm hydrogen sulfide (H2S)... 

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