blindreeper - 25-11-2003 at 03:25
I was reading "Chemistry -second edition" by Ramond Chang and came to this interesting piece of information:
The halogenation of alkanes, that it, the replacement of one or more hydrogen atoms by halogen atoms, is another well-studied kind of reaction. When a
mixture of methane and chlorine is heated above 100*C or irridated with a light of a suitable wavelength, methyl chloride is produced
CH4 + Cl -> CH3Cl + HCl
If chlorine gas is present is sufficeient amount, the reaction can proceed further, as follows:
CH3Cl + Cl2 -> CH2Cl2 + HCl
CH2Cl2 + Cl2 -> CHCl3 + HCl
CHCl3 + Cl2 -> CCl4 + HCl
The second reaction is what stikes my interest. CH2Cl2 is also know as methylene chloride or dichlormethane. It is found in paint strippers.
I was thinking could one bubble Cl2 through DCM to produce trichoromethane?
It may not be the msot cost effective but it is simple and another route...
Comments?
[Edited on 25-11-2003 by blindreeper]
Mumbles - 25-11-2003 at 14:52
That could work if you had the proper light. Otherwise, I have a feeling that your proposed proceedure will need the same reaction environment as the
initial one. Then follow with distillation to remove the unreacted DCM, the wanted Chloroform, and what Carbon Tetrachloride formed.
BromicAcid - 25-11-2003 at 15:08
Like Mumbles said you will need a certain wavelength of light to catalyze the reaction. Or like you mentioned the reaction between methane and
chlorine is run at about 100 C, it gets progressively harder to chlorinate methane as it gets more chlorinated so you would need to run the reaction
will your DCM in the vapor phase at about 100 C. Maybe it could be run in a leibig condenser with nearly boiling water running through it and glass
wool to increase surface area, and some boiling point elevating substance so that you could easily obtain 100 C in the tube, then just run that
condenser into another with cold water.