formaldehyde - Sciencemadness Dot Org

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FORMALDEHYDE
0. Rinser, F., :o Barnol Products, Inc.,; U.S. Patent 2,230,040 UB42).
G. Soliilt, W» British Patent 342,605 '19295.
7. Schrinape, C. F., 'to Perth Amboy Chemical Works) U, S. Patent 1,248,557 (1917).
Gas Absorbents
An absorbent carbon containing; formaldehyde is claimed to have superior
gas-absorbing properties and is recommended for use as a deodorizing
composition 2 .
In World War I?an aqueous solution containing hexamethylenetetramine,
phenol, caustic soda, and glycerin was employed for absorbing and neutralizing
phosgene. This composition was known as phenate hexamine and
was employed in the so-called P. H. helmets for protection against phosgene
1 .
References
1. Bebie, J.f "Explosives, Military Pyrotechnics and Chemical Warfare Agents," p. ISO, New York, Macmill&n
Co., 1343.
2. Block, E. J., U, S, Patent 1,922,416 (1933).
Hydrocarbon Products
Purification and Modification of Hydrocarbon Products from Coal Tar
and Petroleum. As indicated by various industrial patents in this field,
formaldehyde has been found to be of value in the purification and modification
of various hydrocarbon products from petroleum and coal tar. It also
finds application in the synthesis of addition agents for improving' commercial
products of this type.
An early process for the separation of thiophene from benzene rests on
the fact that this compound condenses more rapidly with acid formaldehyde
than does benzene. According to this procedure, 10,000 parts of
benzene containing thiophene are agitated with 1500 parts of 73 per cent
sulfuric acid and 45 parts of 30 per cent formaldehyde at ordinary temperature
for several hours. When the benzene layer ceases to give a test
for thiophene, it is removed from the acid liquor and steam-distilled to
separate it from amorphous condensates 1 .
Following his discovery of the "formolite" reaction (page 236), Nastyukovff
8 patented a procedure for removing unsaturated aromatics and hydroaromatics
from petroleum fractions by treatment with formaldehyde
in the presence of concentrated sulfuric acid and a current of hydrogen gas.
Hecent patents covering the use of formaldehyde for refining hydrocarbon
oils include: the use of formaldehyde and ammonia in a mixture for
treating mineral oil 2 , removal of sulfur from gasoline vapor by passing it
through a mass of copper turnings in the presence of hydrogen chloride and
formaldehyde 7 , and refining cracked hydrocarbon vapors by treatment with
formaldehyde in combination with an acid condensing agent such as hydro-