Scrubbing of Methyl chloride ( CH3Cl)

[Explode]

In one of the reactions there is evolution of Methyl Chloride( CH3Cl). Is there a safe method to scrub the gas, and what should be the scrubbing solution?

 

[kenvlach]

I don't have any experience with methyl chloride, but from looking at its physical properties, suggest the following:

Scrub with water, then periodically do a fractional distillation to remove/recover the methyl chloride.

Methyl chloride: bp -24 C, solubility in water: 280 cc(gas)/100 grams water @ 16 C.

Also, absorption on granular activated carbon is probably a feasible alternative. Suggest that you check with GAC mfr., they will be eager to help.

 

[25362]

Looking through the technical literature I found that monochloromethane is more soluble in organic solvents than in water. You can absorb it by scrubbing with solvents or with water, as kenvlach suggests, and desorb it by use of heat, due to its high vapour pressure.

But one must be careful: although it is moderately flammable by itself, this chemical can form explosive mixtures with air (VP at 25 Celsius:5.75 kPa). The published flammability limits at 25 Celsius and 760 mm Hg: 10.7-17.2 vol % in air. Besides, it is considered moderately toxic: OSHA's TLV is 50 ppm for an 8-hr TWA.

It can be hydrolyzed in boiling caustic (NaOH) solutions:

ClCH₃ + H₂O --> HCl + CH₃OH​

The acid is neutralized by the caustic, while methanol must be disposed of, probably by burning.

 

[dfman]

Methylene chloride leads itself to good removal using BioTrickling Filters

Contact Clean TeQ in Melbourne, Australia for further details

Hope this helps

ctairman
info@cleanteq.com