Difference between revisions of "Calcium Carbide"

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==Description==
 
==Description==
Greyish-black irregular hard lumps or powder. Shipped in water-tight and air-tight metal containers.
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Calcium carbide is a chemical compound with the chemical formula of CaC2. Its main use industrially is in the production of acetylene and calcium cyanamide.<br><br>
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Calcium carbide is produced industrially in an electric arc furnace from a mixture of lime and coke at approximately 2000°C.<br><br>
If containers burst due to rough handling, the contents will suffer damage. The remaining contents may decompose due to the absorption of water from the air, consequent upon exposure. The product resulting from the incidental chemical change may be either:
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The high temperature required for this reaction is not practically achievable by traditional combustion, so the reaction is performed in an electric arc furnace with [[graphite]] electrodes. The carbide product produced generally contains around 80% calcium carbide by weight. The carbide is crushed to produce small lumps that can range from a few mm up to 50 mm. The impurities are concentrated in the finer fractions. The CaC2 content of the product is assayed by measuring the amount of acetylene produced on hydrolysis.<br><br>
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The pure material is colorless, however pieces of technical-grade calcium carbide are grey or brown and consist of only 80-85% of CaC2 (the rest is CaO (calcium oxide), Ca3P2 (calcium phosphide), CaS (calcium sulfide), Ca3N2 (calcium nitride), SiC (silicon carbide), etc.). Because of presence of PH3 (phosphine), NH3 (ammonia), and H2S (hydrogen sulfide), technical-grade calcium carbide has a distinctive smell ([[garlic]] like odour) which some find unpleasant.<br><br>
* A ‘bone dry’ finely powdered talc-like substance (Calcium Hydroxide), which when brought into [[contact]] with water will only give a very poor and insignificant yield of acetylene, as it will be almost entirely composed of ‘slaked lime’, or<br>
 
* A sludge.<br>
 
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Since calcium carbide is known to evolve acetylene only slowly when exposed to damp air, the condition described as above would indicate that the actual wetting and/or commencement of exposure must have taken place quite some time prior to arrival at destination.  
 
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Reference is made to the relevant IMO regulations on hazardous cargo.
 
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<b>Full information on this product is in the process of completion.</b>
 
  
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[[Category:Products]]
 
[[Category:Oil and chemicals]]
 
[[Category:Oil and chemicals]]
[[Category:Products]]
 

Revision as of 12:26, 30 October 2012

Infobox on Calcium Carbide
Example of Calcium Carbide
Calcium Carbide-1.jpg
Facts
Origin
Stowage factor (in m3/t)
Humidity / moisture
Ventilation
Risk factors

Calcium Carbide

Description

Calcium carbide is a chemical compound with the chemical formula of CaC2. Its main use industrially is in the production of acetylene and calcium cyanamide.

Calcium carbide is produced industrially in an electric arc furnace from a mixture of lime and coke at approximately 2000°C.

The high temperature required for this reaction is not practically achievable by traditional combustion, so the reaction is performed in an electric arc furnace with graphite electrodes. The carbide product produced generally contains around 80% calcium carbide by weight. The carbide is crushed to produce small lumps that can range from a few mm up to 50 mm. The impurities are concentrated in the finer fractions. The CaC2 content of the product is assayed by measuring the amount of acetylene produced on hydrolysis.

The pure material is colorless, however pieces of technical-grade calcium carbide are grey or brown and consist of only 80-85% of CaC2 (the rest is CaO (calcium oxide), Ca3P2 (calcium phosphide), CaS (calcium sulfide), Ca3N2 (calcium nitride), SiC (silicon carbide), etc.). Because of presence of PH3 (phosphine), NH3 (ammonia), and H2S (hydrogen sulfide), technical-grade calcium carbide has a distinctive smell (garlic like odour) which some find unpleasant.