Calcium carbide oxide

The original method for the manufacture of ethyne, the action of water on calcium carbide, is still of very great importance, but newer methods include the pyrolysis of the lower paraffins in the presence of steam, the partial oxidation of natural gas (methane) and the cracking of hydrocarbons in an electric arc. 

Thus the hydride is a very efficient carrier of hydrogen. Upon heating, calcium reacts with boron, sulfur, carbon, and phosphoms to form the corresponding binary compounds and with carbon dioxide to form calcium carbide [73-20-7J, CaC2, and calcium oxide [1305-78-8] CaO. 

Commercial calcium carbide is composed of calcium carbide, calcium oxide [1305-78-8] CaO, and other impurities present ia the raw materials. The commercial product s calcium carbide content varies and is sold based on acetjiene yield. Industrial-grade calcium carbide contains about 80% as CaC2,... 

Table 1 fists the more important physical properties of calcium carbide. Additional properties are given in the literature (1). Figure 1 gives the phase diagram calcium carbide—calcium oxide for pure and technical grades. 

Fig. 1. Calcium carbide—calcium oxide phase diagram using A, pure CaC2, and B, technical-grade...

Refractories for Electric Reduction Furnaces. Carbon hearth linings are used in submerged-arc, electric-reduction furnaces producing phosphoms, calcium carbide, all grades of ferrosilicon, high carbon ferrochromium, ferrovanadium, and ferromolybdenum. Carbon is also used in the production of beryllium oxide and beryllium copper where temperatures up to 2273 K ate requited. 

Boron carbide from boron oxide and carbon Calcium silicate from lime and silica Calcium carbide by reaction of lime and carbon Leblanc soda ash... 

Reaction of coke with calcium oxide gives calcium carbide, which on treatment with water produces acetylene. This was for many years an important starting point for the production of acrylonitrile, vinyl chloride, vinyl acetate and other vinyl monomers. Furthermore, during World War II, Reppe developed routes for many other monomers although these were not viable under normal economic conditions. 

Calcium carbide, CaC2, is die raw material for the production of acetylene (used in welding torches). Calcium carbide is produced by reacting calcium oxide with carbon, producing carbon monoxide as a byproduct. When one mole of calcium carbide is formed, 464.8 kj is absorbed. 

Sfi.F-Test D.4A Write the formulas for (a) vanadium(V) oxide (b) calcium carbide (c) germanium tetrafluoride (d) dinitrogen trioxide. 

Calcium carbide can be produced by the direct reaction of carbon with the metal or metal oxide ... 

Willson A process for making calcium carbide by heating calcium oxide with tar or carbon in an electric furnace ... 

Mercuric oxide (5 g.) is dissolved for the most part in a still warm mixture of 110 c.c. of water and 50 c.c. of concentrated sulphuric acid. The mixture is brought into a large hydrogenation flask (Fig. 58, p. 377) and shaken for some time with acetylene prepared from calcium carbide, purified with acid solutions of dichromate and copper nitrate, and collected over saturated sodium chloride solution in a glass gas-holder (capacity 10-15 litres). Before shaking is begun the air present must be displaced by the hydrocarbon. 

Catalytic forms of copper, mercury and silver acetylides, supported on alumina, carbon or silica and used for polymerisation of alkanes, are relatively stable [3], In contact with acetylene, silver and mercury salts will also give explosive acetylides, the mercury derivatives being complex [4], Many of the metal acetylides react violently with oxidants. Impact sensitivities of the dry copper derivatives of acetylene, buten-3-yne and l,3-hexadien-5-yne were determined as 2.4, 2.4 and 4.0 kg m, respectively. The copper derivative of a polyacetylene mixture generated by low-temperature polymerisation of acetylene detonated under 1.2 kg m impact. Sensitivities were much lower for the moist compounds [5], Explosive copper and silver derivatives give non-explosive complexes with trimethyl-, tributyl- or triphenyl-phosphine [6], Formation of silver acetylide on silver-containing solders needs higher acetylene and ammonia concentrations than for formation of copper acetylide. Acetylides are always formed on brass and copper or on silver-containing solders in an atmosphere of acetylene derived from calcium carbide (and which contains traces of phosphine). Silver acetylide is a more efficient explosion initiator than copper acetylide [7],... 

O Calcium oxide, CaO, reacts with carbon in the form of graphite. Calcium carbide, CaC2, and carbon monoxide, CO, are produced in an endothermic reaction. 

Violent reactions occur in dilute mineral acids with evolution of hydrogen. Ca reacts with carbon dioxide on heating, forming calcium oxide and calcium carbide ... 

Calcium carbide is produced by the reaction of calcium oxide with carbon in an electric furnace at temperatures in the range 1,800° to 2,100°C ... 

When pulverized calcium oxide is heated with carhon (crushed coke or anthracite) in an electric furnace, calcium carbide is produced ... 

Carbon dioxide reacts with heated calcium metal, forming calcium carbide and calcium oxide ... 

Calcium Arsenate Calcium Phosphate Calcium Carbide Calcium Chlorate Calcium Chloride Calcium Chloride Calcium Chloride Calcium Chromate Calcium Chromate Calcium Chromate Calcium Cyanide Calcium Peroxide Calcium Fluoride Calcium Hydroxide Calcium Hypochlorite Calcium Phosphate Calcium, Metallic Calcium Nitrate Calcium Nitrate Calcium Oxide Calcium Peroxide Calcium Phosphate Calcium Phosphate Calcium Phosphide Calcium Resinate Calcium Resinate Calcium Resinate Calcium Phosphate Mercuric Chloride Mercurous Chloride... 

A method for the commercial production of acetylene was discovered accidentally in 1892 by Thomas Willson (1860-1915). Willson was experimenting on aluminum production at his company in Spray, North Carolina. He was attempting to produce calcium in order to reduce aluminum in aluminum oxide, A1203. Willson combined coal tar and quicklime in an electric furnace and, instead of producing metallic calcium, he produced a brittle gray substance. The substance was calcium carbide, CaC2, which when reacted with water, produced acetylene. Willsons work led to the establishment of a number of acetylene plants in the United States and Europe during the next decade. 

The traditional method of producing acetylene is from reacting time, calcium oxide (CaO), with coke to produce calcium carbide (CaC2). The calcium carbide is then combined with water to produce acetylene ... 

Acetylene is usually thought of as a coke-derived product via calcium carbide. But acetylene, used for vinyl resins manufacture, has been made by partial oxidation of natural gas methane for over a year now in a major installation in Texas, which is now being expanded (6). Moreover, another Gulf Coast plant now under construction will also produce acetylene from natural gas, utilizing this product for acrylonitrile as well as vinyl chloride production (28). These moves represent a momentous advance, pointing to the future entry of natural gas to an even greater degree into aliphatic syntheses. 

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