Calcium oxide phosgene

An early patent describes the preparation of phosgene and calcium carbide by heating a mixture of calcium oxide, calcium chloride (or NaCl or MgClj) and carbon in an electric furnace [1289a]. The phosgene is formed from the combination of CO and Clj (in the presence of coke) released by heating the mixture. The overall stoicheiometry corresponds to ... 

Magnesium oxide reacts in a similar manner to beryllium oxide at 450 C [360], the reaction being initiated at temperatures as low as 95 C [1094]. Calcium oxide, in contrast, only reacts under similar conditions between 280 and 564 C [1095]. Phosgene is reported to... 

Calcium oxide in a calcium chloride melt can be converted into calcium chloride by treatment with phosgene cf. purification of room-temperature ionic liquids. Section 9.4.3 [649c]. The melt was being used to produce plutonium metal by reducing its oxide with... 

Guanidines have been prepared by the reaction between an amine, or an amine salt, and a host of other reagents, such as a thiourea in the presence of lead or mercuric oxide [83, 157, 158], carbodi-imides [140, 174, 175],calcium cyanamide [176, 177], isonitrile dichlorides [178—180], chloroformamidines [181], dialkyl imidocarbonates [182], orthocarbonate esters [183], trichloro-methanesulphenyl chloride [184], and nitro- or nitroso-guanidines [185-188]. Substituted ureas can furnish guanidines, either by treatment with amines and phosphorus oxychloride [189], or by reaction with phenylisocyanate [190] or phosgene [191]. 

CARBONA (56-23-5) Becomes corrosive on contact with water. Explosive reaction on contact with burning wax or uranium, alkali metals, potassium sulfur diimide, triethylalu-minum, triethyldialuminum trichloride. Oxidative decomposition at elevated temperatures on contact with flame, hot surfaces, or welding arcs, forming hydrogen chloride and phosgene. Forms heat-, impact-, and friction-sensitive explosive mixtures with calcium disilicide. 

Chloroform is also prepared by chlorination of methane but also by treatment of ethanol with bleaching powder. Because of its tendency to decompose, chloroform contains phosgene, hydrogen chloride, and chlorine as well as other chlorination products of methane it is usually stabilized by addition of 0.5-1.0% of ethanol. The impurities formed by decomposition are removed by washing with water or dilute potassium hydroxide solution. Further purification, which is usually superfluous, can be effected as for methylene dichloride. The same drying agents as in that case may be used of these, calcium chloride and phosphoric oxide are most efficient in removing also the ethanol. 

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