Silver News
Silver Catalysts Critical to Plastics Industry
By Samuel Etris, Senior
Technical Consultant to The Silver Institute
The steadily growing demand for plastics
is driving the increasing need for silver catalysts which
are crucial to the production process.
Silver has long been relied upon to increase
the efficiency of chemical reactions without entering into
the reaction itself, and this use in the United States has
been increasing at about 300,000 ounces per year over the
past six years. According to the 1994 World Silver Survey,
some 4 million ounces were added to the U.S. silver catalyst
inventory during 1993 alone, giving a total inventory of some
12.8 million ounces in continuous use by the U.S. chemical
process industry. According to The Catalyst Group, Spring
House, PA, the world silver catalyst inventory is about 23
million ounces.
A major use of silver in the chemical industry
is for ethylene oxide with more than 14 billion pounds per
year produced worldwide. About 30 percent of this production
is used to produce polyester fibers, audio and video tape,
and molded items such as insulating handles for stoves, key
tops for computers, electrical control knobs, domestic appliance
components, and electrical connector housings.
The second major use of silver is to oxidize
methyl (wood) alcohol into formaldehyde. The world production
of formaldehyde, most of which is produced with silver catalysts,
exceeds 15 billion pounds.
Formaldehyde is a prime component in hard,
transparent and flame resistant thermoset resins whose uses
range from laminating plywood and building beams to making
plastic housings for television sets, computers, and electrical
switch boxes. These products resist high temperatures, have
excellent dimensional stability, and do not swell in water
or in organic solvents.
Mixed with other chemicals, formaldehyde
produces resins for the manufacture of particle board and
adhesives for the building industry.
Manufacturers of silver catalysts include:
Degussa/Metz Corp., South Plainfield, NJ; Du Pont Corp., Wilmington,
DE; Handy & Harman, Fairfield, CT; Heraeus, Inc., Newark,
NJ; Johnson Matthey, Salt Lake City, UT; Shell Oil Corp.,
Houston, TX; Scientific Design,
Little Ferry, NJ; and Union Carbide, Charleston, WV.
Silver News - December 1994/January
1995
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