Calcium acetate carbide

Cadmium Acetylide A71-L Cadmium Amide A169-L Cadmium Azide A526-L Cadmium Azidodithiocarbonate A636-R Cadmium Diazide A526-L Calcium Acetate A28-L Calcium Acetylide A71-L Calcium Azide A527-R Calcium Carbide. See under Acetylides and Carbides A71-R... 

Amyl acetate Amyl alcohol Arsenic compounds Butyl acetate Butyl alcohol Calcium acetate Calcium carbide Calcium chloride Carbon bisulfide... 

Bromic acid Bromine, anhydrous Butadiene Butane Butyl acetate Butyl chloride Butyl ether Butyl lactate Butyl mercaptan Butyl chloride Cadmium chloride Cadmium nitrate Cadmium sulfate Cadmium sulfide Calcium acetate Calcium arsenate Calcium bicarbonate Calcium bisulfide Calcium hydrosulfide Calcium carbide Calcium carbonate Calcium chlorate Calcium chloride Calcium chromate Calcium fluoride Calcium hydroxide Calcium h) pochlorite Calcium nitrate Calcium oxide Calcium peroxide Calcium phosphate Calcium stearate Calcium sulfate Calcium sulfide Calcium sulfite Cane sugar liquors Capric acid Carbamate Carbon bisulfide Carbon dioxide Carbon disulfide Carbon fluorides Carbon monoxide Caustic lime... 

Calcium carbide has been used in steel production to lower sulfur emissions when coke with high sulfur content is used. The principal use of carbide remains hydrolysis for acetylene (C2H2) production. Acetylene is widely used as a welding gas, and is also a versatile intermediate for the synthesis of many organic chemicals. Approximately 450,000 t of acetylene were used aimuaHy in the early 1960s for the production of such chemicals as acrylonitrile, acrylates, chlorinated solvents, chloroprene, vinyl acetate, and vinyl chloride. Since then, petroleum-derived olefins have replaced acetylene in these uses. 

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. 

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. 

Ethylene is produced in quantity using acetylene or propylene as feedstock to make a large number of products (Figure 7.2-3) such as acetaldehyde, acrylonitrile, acetic acid, and acetic anhydride. These are made generally from acetylene which is made from calcium carbide. 

Normal Fischer esterification of tertiary alcohols is unsatisfactory because the acid catalyst required causes dehydration or rearrangement of the tertiary substrate. Moreover, reactions with acid chlorides or anhydrides are also of limited value for similar reasons. However, treatment of acetic anhydride with calcium carbide (or calcium hydride) followed by addition of the dry tertiary alcohol gives the desired acetate in good yield. 

A 500-mI, three-necked, round-bottom flask is fitted with a condenser, a thermometer, and a mechanical stirrer all openings are protected by drying tubes. In the flask is placed a mixture of 61.2 g (0.61 mole) of acetic anhydride and 27 g (about 0.4 mole) of finely pulverized calcium carbide, and the mixture is refluxed for 2 hours. After cooling to 70°, 29.6 g (0.4 mole) of dry r-butyl alcohol is added and the mixture is refluxed for 4 days with continuous stirring. The mixture is cooled and the thick slurry is decomposed by careful addition to ice, followed by steam distillation. The ester layer is separated. 

Acetic anhydride (75 ml) and pulverized calcium carbide (15 g) are refluxed for 60 minutes in an apparatus as described above. Sufficient benzene is then added to reduce the boiling temperature to 110-112°. After cooling, 14.4 g of pinacol is introduced, and the mixture is refluxed with stirring for 30 hours. The cooled mixture is then stirred into ice, extracted into ether and washed with sodium carbonate solution. The solution is dried, then filtered, and theether is evaporated. The residue is clarified with Norit and recrystallized from benzene-petroleum ether or methanol, mp 67-68°. 

Boron trifluoride-acetic acid complex Harshaw Chemical Co., Allied Chemical Co. 1,5-Cyclooctadiene A, MCB Sulfur dichloride MCB Boron trifluoride etherate EK, MCB Mercuric acetate MCB Norbornene MCB Calcium carbide MCB Pinacol EK, MCB... 

Another vinyl-based fiber, polyvinyl alcohol, or vinal, was developed in Japan but has not been produced or used in the United States. As such, it illustrates the importance of both relative availability of raw materials and differences in markets, in the success of a chemical product. Acetylene made from calcium carbide is converted to vinyl acetate, which, following polymerization, is saponified to polyvinyl alcohol. 

The synthesis of acetaldehyde by oxidation of ethylene, generally known as the Wacker process, was a major landmark in the application of homogeneous catalysis to industrial organic chemistry. It was also a major step in the displacement of acetylene (made from calcium carbide) as the feedstock for the manufacture of organic chemicals. Acetylene-based acetaldehyde was a major intermediate for production of acetic acid and butyraldehyde. However the cost was high because a large energy input is required to produce acetylene. The acetylene process still survives in a few East European countries and in Switzerland, where low cost acetylene is available. 

Isopropylideneglycerol, a five-membered cyclic hydroxy ketal from acetone and glycerol, is prepared in 90% yield by removing the liberated water by an azeotropic distillation. In another procedure, calcium carbide is added directly to the reaction mixture as a desiccant. Acetaldehyde and benzaldehyde, unlike acetone, react with glycerol to form a mixture of the five- and six-membered cyclic hydroxy acetals. Alkoxy acetals are made by the acetalization of a,/3-olefinic aldehydes in weakly acidic solutions however, the addition of alcohol to the double bond may not go to completion. ... 

Bleach (chloride of lime) Bromine Butyl acetate Butyl phthalate Butyric acid Calcium carbide Calcium cyanamide Calcium hypochlorite Calcium nitrate Calcium potassium ferrocyan-ide (double salt)... 

Acylation of tertiary alcohols6 [1, 106, before references]. Tertiary alcohols can be esterified with carboxylic acids or anhydrides in good yield in the presence of calcium hydride or calcium carbide. /-Butyl acetate is obtained in 80% yield from f-butanol and acetic anhydride. 17a-Methyltcstosterone is acetylated in 89-96% yield. 

Estimated yields show the consumption of 170 kg. of calcium carbide representing 100 kg. of coke and 600 K.w.h. of electrical energy per 100 Kg. of acetic acid formed.124... 

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