ACETYLENE-DERIVED CHEMICALS

Acetylene [74-86-2]y C2H2, is an extremely reactive hydrocarbon, principally used as a chemical intermediate (see Hydrocarbons, acetylene). Because of its thermodynamic instability, it cannot easily or economically be transported for long distances. To avoid large free volumes or high pressures, acetylene cylinders contain a porous solid packing and an organic solvent. Acetylene pipelines are severely restricted in size and must be used at relatively low pressures. Hence, for large-scale operations, the acetylene consumer must be near the place of acetylene manufacture. 

Historically, the use of acetylene as raw material for chemical synthesis has depended strongly upon the availability of alternative raw materials. The United States, which until recently appeared to have limitless stocks of hydrocarbon feeds, has never depended upon acetylene to the same extent as Germany, which had more limited access to hydrocarbons (1). During World War I the first manufacture of a synthetic rubber was undertaken in Germany to replace imported natural rubber, which was no longer accessible. Acetylene derived from calcium carbide was used for preparation of 

Methyl rubber, obtained by polymerization of this monomer, was expensive and had inferior properties, and its manufacture was discontinued at the end of World War I. By the time World War II again shut off access to natural rubber, Germany had developed better synthetic rubbers based upon butadiene 

In the United States butadiene was prepared initially from ethanol and later by cracking four-carbon hydrocarbon streams (see Butadiene). In Germany butadiene was prepared from acetylene via the following steps acetylene — acetaldehyde — 3-liydroxybutyraldehyde — 1,3-butanediol —  

Toward the end of the war, an alternative German route to butadiene was introduced which required much less acetylene  

Acetjiene [74-86-2] is an extremely reactive hydrocarbon, principally used as a chemical iatermediate (see Hydrocarbons, acetylene). Because of its 

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PEROXIDES AND PEROXIDE COMPOUNDS - ORGANIC PEROXIDES] (Vol 18) -frombutanediol [ACETYLENE-DERIVED CHEMICALS] (Voll)... 

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