Typical procedure, from Hale in SM library: Methyl alcohol (100 ml) is placed in a flask which is kept at a temperature of 40°, and connected to
a horizontal combustion tube in which a roll of copper foil (5 cm. long) is placed. The other end of the combustion tube is connected to a condenser
and a well cooled receiver.
A stream of air is driven through the alcohol causing a mixture of air and alcohol vapour to pass through the copper coil, which should be heated
until it just glows. The reaction will proceed without further heating and a solution of formaldehyde in methyl alcohol will collect in the receiver.
Small explosions on the copper do no harm; but the temperature should not exceed a dull red heat or some of the aldehyde will be decomposed.
A much improved yield (about 80 per cent.) may be obtained by substituting pumice, coated with a mixture of silver and copper, for the roll of copper
foil.
Perhaps this refers to precipitated metal.
Oh, I want to. Maybe, though it will never be PC, it may be best if someone is, someone not having to represent the staff, in the best interests of a
semi-serious science forum/information depository with 18989 threads and over a quarter million posts. This is nothing new for anyone who has
accidentally read several of my posts. I'm a smartass by nature and others for sure are not good at it, and obviously a lifelong antisocial type.
There are threads that are much too long, see them. This is obviously a narrowly defined one, yet we want to start new branches of discussion in it
like trioxane and preparation of acetaldehyde and paraformaldehyde (which belong in and already are in appropriate threads). If you support this,
that's your problem, I want no part of it. Explanation seemed unnecessary. |