The Chemistry of Powder and Explosives - Sciencemadness Dot Org

UTILIZATION OF FORMALDEHYDE 277
catalyst for the purpose. Carbon monoxide and hydrogen (equimolecular
amounts of each) arc produced as water gas when
steam is passed over hot coke.
C + H2O > CO + Ha
Additional hydrogen, from the action of iron on steam or from
the electrolysis of water, is added to the water gas to provide the
mixture which is needed for the synthesis of methyl alcohol.
CO + 2H2
> CH,—OH
It is evident that carbon dioxide may be used instead of the
monoxide if a correspondingly larger amount of hydrogen is also
USed- CO2 + 3H2 > CHa—OH + H2O
Methyl alcohol in fact is made in this manner from the carbon
dioxide which results from certain industrial fermentations. When
methyl alcohol vapor is mixed with air and passed over an
initially heated catalyst of metallic copper or silver gauze, oxidation
occurs, sufficient heat is evolved to maintain the catalyst at
a bright red, and formaldehyde is formed.
2CH.-0H + O2
> 2H2O + 2
Of the several explosives which are preparable from formaldehyde,
two are the most powerful and brisant of the solid high
explosives which are suitable for military use. One of these,
cyclotrimethylenetrinitramine or cyclonite, is a nitroamine and
is discussed in the chapter which is devoted to those substances.
The other, pentaerythrite tetranitrate or PETN, is a nitric ester.
Both may be prepared from coke and air.
Formaldehyde enters readily into combination with substances
which add to its unsaturated carbonyl group. If a substance containing
an active hydrogen adds to formaldehyde or condenses
with it, the active hydrogen attaching itself to the oxygen of the
formaldehyde and the rest of the molecule attaching itself to the
carbon, the result is that the position originally occupied by the
active hydrogen is now occupied by a —CH^—OH or methylol
group. Hydrogens which are active in condensation reactions are
those which are a- to a carbonyl, a nitro, or a cyano group, etc.,
that is, they are attached to a carbon atom to which a carbonyl,
H