The chlorination of methane proceeds through a radical mechanism. Like most radical mechanisms there are three steps: initiation, propagation and termination.
The chlorination of methane does not necessarily stop after one chlorination. It may actually be very hard to get a monosubstituted chloromethane. Instead di-, tri- and even tetra-chloromethanes are formed.
Demand for methylene chloride on the export market had been steadily increasing since January, producers said, which had pushed prices to levels some had not previously expected.
Globally, about 90-95% of the chloroform is used as a precursor for HCFC-22, which is used in refrigerants and fluoropolymers such as polytetrafluoro-ethylene (PTFE).