CHjCls Dichloromethane

Chloromethane, CHjCl Dichloromethane, CH C , (i.e. Methylene Chloride) Chloroform, CHCI3 Carbon Tetrachloride, CCl l -Didilotoethane, GHjOGH Q... 

Chloromethane, if mixed with its own volume of chlorine and exposed to light, yields a dichloromethane, thus CHjCl + Cl2 = CH C1, + HC1. This compound, which, like chloromethane, is also a gas soluble in ether, on treating its solution with sodium, loses chlorine and is converted into ethylene, thus CH2Cl2 + 4Na + CI2CH2 = 4NaCl H H... 

Monochlormethyl chlorid—Methene chlorid—Dichloromethane —Methylene chlorid—Chloromefhyl—CHjCl,Cl—85—is obtained by the action of Cl upon CH3CI or by shaking an alcoholic solution of chloroform with powdered zinc and a little ammonium hy-drozid. In either case the product must be purified. 

Chlorinated hydrocarbons have been very much utilized as industrial solvents for degreasing, paint stripping and dry-cleaning. Mostly trichlorethylene CjHCl, alternatively methylene chloride (dichloromethane) CHjCl or tetrachlorethylene (per-chlorethylene) CClj CClj, have been used. 

Figure 98. Methane chlorination by the Hoechst method (production of dichloromethane and trichloromethane) a) Loop reactor b) Process gas cooler c) HCl absorption d) Neutralization system e) Compressor f) First condensation step (water) g) Gas drying system h) Second condensation system and crude product storage vessel (brine) i) Distillation columns for CHjCl, CH2CI2, and CHCI2... 

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