Methyl chloride manufacturing methods

Methylene dichloride and chloroform may be produced by modified methods using a mixture of chlorine, methane, and methyl chloride as feed. Chlorination is run at 350-400°C reactor temperature at slightly above atmospheric pressure. A 2.6 1 chlorine methane ratio results in an optimal yield of chloroform. Alternatively, excess methane is reacted with chlorine at 485-510°C to produce methylene dichloride as the main product.181 The predominant method, however, still is the chlorination of methyl chloride manufactured by the reaction of methyl alcohol and hydrogen chloride.181... 

Chloroform can be manufactured from a number of starting materials. Methane, methyl chloride, or methylene chloride can be further chlorinated to chloroform, or carbon tetrachloride can be reduced, ie, hydrodechlorinated, to chloroform. Methane can be oxychlorinated with HCl and oxygen to form a mixture of chlorinated methanes. Many compounds containing either the acetyl (CH CO) or CH2CH(OH) group yield chloroform on reaction with chlorine and alkali or hypochlorite. Methyl chloride chlorination is now the most common commercial method of producing chloroform. Many years ago chloroform was almost exclusively produced from acetone or ethyl alcohol by reaction with chlorine and alkali. 

Method of synthesis the manufacture of the bromobutyl rubber is a two step process the polymerization of isobutylene and isoprene to produce butyl rubber, followed by bromination to form bromobutyl rubber a slurry of fine particles of butyl rubber dispersed in methyl chloride is formed in the reactor after Lewis acid initiation bromine is added to the butyl solution in highly agitated reaction vessels ... 

Bulk chlorosilanes can be manufactured via several methods, but the primary one, referred to as the direct process [31], involves the catalytic reduction of methyl chloride. The reaction, which requires the presence of a catalyst and heat, is as follows ... 

The initiator can be a radical, an acid, or a base. Historically, as we saw in Section 7.10, radical polymerization was the most common method because it can be carried out with practically any vinyl monomer. Acid-catalyzed (cationic) polymerization, by contrast, is effective only with vinyl monomers that contain an electron-donating group (EDG) capable of stabilizing the chain-carrying carbocation intermediate. Thus, isobutylene (2-methyl-propene) polymerizes rapidly under cationic conditions, but ethylene, vinyl chloride, and acrylonitrile do not. Isobutylene polymerization is carried out commercially at -80 °C, using BF3 and a small amount of water to generate BF3OH- H+ catalyst. The product is used in the manufacture of truck and bicycle inner tubes. 

A recent achievement worthy of note is the manufacture of microspheres containing an inert gas, e.g. nitrogen, or a volatile liquid, such as the freons The patent literature contains methods for producing microspheres based on poly(vinyl chloride) and poly(divinyl chloride), containing isobutane or carbon tetrachloride 52>, and based on poly(methyl methacrylate), containing neopentane . Microspheres containing liquid dyes and oils are also used to make syntactic foams 58>. 

Crystal Violet.—The preparation of this dye, which is the chloride of hexamethyl-pararosaniline, illustrates a method of preparing dyes of this class. The compound is manufactured by treating dimethylaniline with carbonyl chloride or tetra-methyl-diamino-benzophenone chloride —... 

An important plant protection agent based on catechol is carbofuran, manufactured by Bayer diViA FMC, It is obtained by the reaction of catechol with methallyl chloride, followed by Claisen rearrangement at around 200 °C and ring closure to the respective benzofuran, with subsequent reaction of the hydroxyl group with methyl isocyanate in the presence of triethanolamine. (An alternative method of synthesis is based on o-nitrophenol). 

The other big problem was the hafnium content of natural zirconium. In the actual tubes the hafnium content must be lower than 100 ppm, because hafnium absorbs neutrons 550 times more strongly than zirconium. Zircon sand, the most important ore, has a hafnium content of 1.5-2.596 (relative to zirconium). Thus it was necessary to find a separation method with which hafnium-free zirconium could be manufactured. The solution of this problem was liquid-liquid extraction. From an impure zirconium solution in hydrochloric acid, iron is first removed by solvent extraction. Then ammonium thiocyanate is added to the chloride solution containing Zr -i- Hf. Hafnium is extracted into an organic phase of methyl isobutyl ketone. The pure zirconium solution in the water phase is worked up for zirconium. Hafnium is recovered from the ketone solution by scrubbing with dilute sulfuric acid. 

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