Some smurf had a dream of a 55 gallon drum with a serious condensor with an exhaust tube into muratic acid to keep the smell to a minimum. Filled with 80 liters of methanol, 40 kilos of thick aluminum pipe or rod, 10 grams mercury chloride disolved into some of the methanol 1st, probably a few liters of water though leaving it out should let it run slower and less hot which may be important much more important on a huge scale. 40 liters of nitromethane added over time, though if the aluminum is thick enough you may be able to add it all at once. Heat gently to reflux and keep at reflux for 8 to 24 hours. Not sure on anything this big if you can get away with adding all at once, though the thicker the aluminum the more likely you can. Distill off the methylamine methanol solution. Hopefully you get 75 to 80 liters of 40 to 50 percent solution. Then basify slowly the 55 gallon drum with lye solution or you will get a huge boil over. When basifying vent it into muyratic acid. The muratic acid will end up with methylamine hcl and probably also ammonium chloride from the ammonia gas released when basifying. Evaporate off the muratic then add excess hot methanol, stir well, chill then freeze, filter, to seperate out the ammonium chloride and methylamine hcl solution. Rinse the methylamine hcl with acetone to clean it up.
This was a big dream but there are a number of posts on smaller scale methylamine production from nitromethane.