Iron pyrite, roasting

Cement, dry process Cement, wet process, 44% water Limestone calcination Dolomite calcination Alumina preparation Barium sulfide preparation Ignition of inorganic pigments Iron pyrite roasting... 

The third major source of sulfur production is metal sulfide minerals, such as the mineral iron(II) disulfide (also known as iron pyrite). Roasting iron pyrite in the absence of air causes the sulfur to disproportionate (react with itself) to form iron(ll) sulfide and el ental sulfur. 

Total 1991 world production of sulfur in all forms was 55.6 x 10 t. The largest proportion of this production (41.7%) was obtained by removal of sulfur compounds from petroleum and natural gas (see Sulfurremoval and recovery). Deep mining of elemental sulfur deposits by the Frasch hot water process accounted for 16.9% of world production mining of elemental deposits by other methods accounted for 5.0%. Sulfur was also produced by roasting iron pyrites (17.6%) and as a by-product of the smelting of nonferrous ores (14.0%). The remaining 4.8% was produced from unspecified sources. 

The principal direct raw materials used to make sulfuric acid are elemental sulfur, spent (contaminated and diluted) sulfuric acid, and hydrogen sulfide. Elemental sulfur is by far the most widely used. In the past, iron pyrites or related compounds were often used but as of the mid-1990s this type of raw material is not common except in southern Africa, China, Ka2akhstan, Spain, Russia, and Ukraine (96). A large amount of sulfuric acid is also produced as a by-product of nonferrous metal smelting, ie, roasting sulfide ores of copper, lead, molybdenum, nickel, 2inc, or others. 

Siilfuric acid from iron pyrites Paint pigments roasting of metallic oxides Refractory clays calcination of refractory clay to reduce shrinkage Foundry sand removal of carbon from used foundry sand Fullers earth calcination of fuller s-earth material... 

The modem process uses a potassium-sulfate-promoted vanadium(V) oxide catalyst on a silica or kie,selguhr support. The SO2 is obtained either by burning pure sulfur or by roasting sulfide minerals (p. 651) notably iron pyrite, or ores of Cu, Ni and Zn during the production of these metals. On a worldwide basis about 65% of the SO2 comes from the burning of sulfur and some 35% by the roasting of sulfide ores but in some countries (e.g, the UK) over 95% conies from the former. 

The principal objection to this method of assay is the largo amount of lead which is produced for cupellation, since pure iron pyrites affords, when thus treated, eight and a half partB of lead, whilst sulphate-of antimony and grey copper ore yield from six to seven parts. This inconvenience, as well as the trouble of roasting, may be avoided by the cautious and gradual addition of nitrate of potassa, which effects the partial oxidation of the mineral, and enables tho skilful assayer to pro-... 

Figure 1730. Kilns and hearth furnaces Walas, 1959). (a) Temperature profiles in a rotary cement kiln, (b) Space velocities in rotary kilns, (c) Continuous lime kiln for production of approximately 55tons/24hr. (d) Stirred salt cake furnace operating at 1000°F, 11-18 ft dia, 6-10 tons salt/24 hr. (e) Multiple-hearth reactor one with 9 trays, 16 ft dia and 35 ft high roasts 1250 lb/hr iron pyrite. (f) Siements-Martin furnace and heat regenerators a hearth 13 ft wide and 40 ft long makes 10 tons/hr of steel with a residence time of 10 hr.

You can produce your own vitriol though it takes some time. Collect together ten to twenty pounds (at least) of iron pyrite (FeS) and grind it to powder. Spread the powder out onto a large flat iron tray then alternately roast it gently and spray with rainwater to moisten, then dry. 

In the laboratory ferric oxide may be obtained in a variety of ways. Thus when ferric hydroxide or sulphate is strongly heated ferric oxide remains behind, and the same applies if ferric chloride or sulphide, ferrous oxide or carbonate, or indeed the majority of ferrous salts,3 are heated in contact with air. Several of these methods are adopted on a manufacturing scale. For example, in the manufacture of sulphuric acid 4 iron pyrites is roasted in air, leaving a residue of ferric oxide. Thus —... 

Ferric oxide is manufactured in large quantities for use as a pigment by roasting ferrous sulphate obtained by weathering iron pyrites, as described on page 147. 

Sulfuric acid is the chemical produced in the United States with the highest volume of production. In one of the earliest processes used to make it, an ore containing iron pyrites (FeS2) is roasted... 

A total of 52.66 10 t of sulfur-containing raw materials (on the basis of sulfur content) was produced for further processing in 1993. 65% of this was elemental sulfur, 14% iron pyrites and the rest consists of flue gases from the roasting of non-ferrous metal sulfides, hydrogen sulfide and gypsum. 

Essentially, sulphuric acid is a thick, oily, water solution of sulphur trioxide. Concentrated acid is made commercially by the contact" process in which sulphur dioxide, produced by burning sulphur or roasting iron pyrites, is passed over a heated catalyst, which causes it to combine with oxygen of the air to form sulphur trioxide. Since the finely divided sulphur trioxide cannot be dissolved directly in water, it is added to concentrated sulphuric acid, forming a superconcentrated or "fuming" acid which is easily diluted to the required strength. 

An iron pyrite ore containing 85.0% FeSi and 15.0% gangue (inert dirt, rock, etc.) is roasted with an amount of air equal to 200% excess air according to the reaction... 

Derivation By roasting arsenopyrite and iron pyrites and sublimation. 

Derivation From sulfur, pyrite (FeS2), hydrogen sulfide, or sulfur-containing smelter gases by the con-tactprocess (vanadiumpentoxide catalyst). The first step is combustion of elemental sulfur or roasting of iron pyrites to yield sulfur dioxide. Then follows the critical reaction, catalytic oxidation of sulfur dioxide to sulfur trioxide. 

Hypothesizing Roasting iron pyrite, FeS2, can 2. Acquiring Information Find out how sulfuric replace burning sulfur in Step 1 to produce acid is used to manufacture hydrochloric acid... 

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