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Chemical manufacturing, chemicals used acetylene

Aliphatic Chemicals. The primary aliphatic hydrocarbons used in chemical manufacture are ethylene (qv), propjiene (qv), butadiene (qv), acetylene, and / -paraffins (see Hydrocarbons, acetylene). In order to be useflil as an intermediate, a hydrocarbon must have some reactivity. In practice, this means that those paraffins lighter than hexane have Httle use as intermediates. Table 5 gives 1991 production and sales from petroleum and natural gas. Information on uses of the C —C saturated hydrocarbons are available in the Hterature (see Hydrocarbons, C —C ). [Pg.366]

Chemical Uses. In Europe, products such as ethylene, acetaldehyde, acetic acid, acetone, butadiene, and isoprene have been manufactured from acetylene at one time. Wartime shortages or raw material restrictions were the basis for the choice of process. Coking coal was readily available in Europe and acetylene was easily accessible via calcium carbide. [Pg.393]

Although the current source of acetylene is petroleum, it can be manufactured from calcium carbide, a product of the reachon of limestone and coke (carbon). During World War II, Germany, having a shortage of petroleum, used the latter technology to develop a chemical industry based on acetylene. [Pg.57]

Acetylene (Figure 13.1) is widely used as a chemical raw material and fuel for oxyacetylene torches. It was once the principal raw material for the manufacture of vinyl chloride (see reaction 13.2.4), but other synthetic routes are now used. Acetylene is a colorless gas with an odor resembling garlic. Though not notably toxic, it acts as an asphyxiant and narcotic and has been used for anesthesia. Exposure can cause headache, dizziness, and gastric disturbances. Some adverse effects from exposure to acetylene may be due to the presence of impurities in the commercial product. [Pg.298]

Chloroprene (boiling point 59.4°C, density 0.9583) is, chemically, a chlorovinyl ester of hydrochloric acid and can be manufactured by polymerizing acetylene to vinyl acetylene using a weak solution containing ammonium chloride (NH4C1), cuprous chloride (Cu2Cl2), and potassium chloride (KC1) as catalyst. The off-gas from the reactor has its water condensed out and is then fractionated. Aqueous hydrochloric acid at 35 to 45 °C is then reacted with the vinyl acetylene in the presence of cupric chloride to give chloroprene (2-chloro-l,3-butadiene). [Pg.168]

In other oxygen applications, metal fabrication involves cutting and welding with an oxygen-acetylene torch. Chemical manufacture use includes the formation of ethylene oxide, acrylic acid, propylene oxide, and vinyl acetate. Miscellaneous uses include sewage treatment, aeration, pulp and paper bleaching, and missile fuel. [Pg.370]

In the early days of the chemical industry, acetylene was a key starting material for many important products. Initially it was obtained for chemical purposes by reaction of calcium carbide with water but that practice has given way to acetylene recovery from hydrocarbon cracking, so that now 86 percent of acetylene used in chemical manufacturing is made in this way. Owing to difficulty in its safe collection and transport, it is almost always used where it is prepared. [Pg.353]

This invention has its roots in Reppe chemistry. In the late 1930s, Reppe in Germany had developed a number of manufacturing processes for bulk chemicals, where acetylene was used as one of the basic building blocks. Even today BASF and Rohm Hass manufacture large quantities of acrylic acid and its esters by hydrocarboxylation of acetylene. This reaction, 4.12, is catalyzed by a mixture of NiBr2 and Cul. It involves high pressure (100 bar) and temperature (220°C), and mechanistically is not fully understood. [Pg.71]

Miller, S.A., Acetylene Its Properties, Manufacture and Uses, Vol. 1, Ernest Benn, London, 1965,419. Tedeschi, R.J., Acetylene-based Chemicals from Coal and Other Natural Resources, Marcel Dekker, New York, 1982, 20. [Pg.316]

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. [Pg.101]

Beilstein Handbook Reference) Acetylene, methyl- Allylene BRN 0878138 CCRIS 6830 EINECS 200-828-4 HSDB 2508 Methyl acetylene Methylacetylene Propine Propyne. Used in chemical manufacturing. Colorless gas mp = -102-7° bp = -23.2° d = 0.607 poorly soluble in H2O, soluble in organic solvents. [Pg.528]

In the meantime Willson returned to Canada. He there established carbide operations in Merriton, Ontario, and at Shawinigan Falls, Quebec He formed the International Marine Signal Co. to manufacture carbide-energized buoys, and applied himself to the use of the electric furnace for smelting phosphate ores in his remaining years (W). Willson died in 1915, by which time he had seen his invention produce 90,000 tons of calcium carbide annually by 1904 and 250,000 by 1910, from zero in 1892 ( ). He perhaps would have been amazed to have witnessed the growth in the chemical uses of acetylene equivalent to one million tons per year of calcium carbide by 1960, produced in continuous furnaces which were 30 feet in diameter by 15 feet tall, each rated at 30,000 kw ( ). Nor could he have foreseen his furnace eventually supplanted as a source of acetylene by yet another electrothermic process, the direct formation of acetylene in an electric arc used to crack hydrocarbons such as natural gas. [Pg.491]

Yearly production of acetic acid in the United States is approximately 10 kg, a volume that ranks it at the top of the list of organic chemicals manufactured by the US chemical industry. The first industrial synthesis of acetic acid was commercialized in 1916 in Canada and Germany, using acetylene as a feedstock. The process involved two stages (1) hydration of acetylene to acetaldehyde followed by (2) oxidation of acetaldehyde to acetic acid by molecular oxygen, catalyzed by cobalt (III) acetate. [Pg.712]

Ethyne is the starting point for the manufacture of a wide range of chemicals, amongst which the most important are acrylonitrile, vinyl chloride, vinyl acetate, ethanal, ethanoic acid, tri- and perchloro-ethylene, neoprene and polyvinyl alcohol. Processes such as vinylation, ethinylation, carbonylation, oligomerization and Reppe processes offer the possibility of producing various organic chemicals cheaply. Used in oxy-acetylene welding. [Pg.169]

Historically, the use of acetylene as raw material for chemical synthesis has depended strongly upon the avadabihty of alternative raw materials. The United States, which until recendy 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 Wodd War 1 the first manufacture of a synthetic mbber was undertaken ia Germany to replace imported natural mbber, which was no longer accessible. Acetylene derived from calcium carbide was used for preparation of... [Pg.101]

In the 1980s cost and availabiUty of acetylene have made it an unattractive raw material for acrylate manufacture as compared to propylene, which has been readily available at attractive cost (see Acetylene-DERIVED chemicals). As a consequence, essentially all commercial units based on acetylene, with the exception of BASF s plant at Ludwigshafen, have been shut down. AH new capacity recendy brought on stream or announced for constmction uses the propylene route. Rohm and Haas Co. has developed an alternative method based on aLkoxycarbonylation of ethylene, but has not commercialized it because of the more favorable economics of the propylene route. [Pg.152]

The pattern of commercial production of 1,3-butadiene parallels the overall development of the petrochemical industry. Since its discovery via pyrolysis of various organic materials, butadiene has been manufactured from acetylene as weU as ethanol, both via butanediols (1,3- and 1,4-) as intermediates (see Acetylene-DERIVED chemicals). On a global basis, the importance of these processes has decreased substantially because of the increasing production of butadiene from petroleum sources. China and India stiU convert ethanol to butadiene using the two-step process while Poland and the former USSR use a one-step process (229,230). In the past butadiene also was produced by the dehydrogenation of / -butane and oxydehydrogenation of / -butenes. However, butadiene is now primarily produced as a by-product in the steam cracking of hydrocarbon streams to produce ethylene. Except under market dislocation situations, butadiene is almost exclusively manufactured by this process in the United States, Western Europe, and Japan. [Pg.347]


See other pages where Chemical manufacturing, chemicals used acetylene is mentioned: [Pg.373]    [Pg.394]    [Pg.141]    [Pg.46]    [Pg.102]    [Pg.312]    [Pg.62]    [Pg.1232]    [Pg.716]    [Pg.323]    [Pg.245]    [Pg.634]    [Pg.129]    [Pg.764]    [Pg.112]    [Pg.215]    [Pg.141]    [Pg.107]    [Pg.92]    [Pg.114]    [Pg.180]    [Pg.385]    [Pg.390]    [Pg.75]    [Pg.120]    [Pg.232]   
See also in sourсe #XX -- [ Pg.2 , Pg.28 ]




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