by John D. Rockefeller, Sohio was a petroleum company known for efficient
refining and skilled marketing. Before 1953, it had done no research
on chemicals or petrochemicalsresearch was limited to the development
of petroleum products and processes. No one among the 80 researchers
working at Sohio's laboratory, then located on Cornell Road in Cleveland,
was thinking about a shortcut to world-class acrylonitrile production.
picture changed when Franklin Veatch, a research supervisor reporting
to E.C. Hughes, director of research, proposed that converting light
refinery gases such as the aliphatic hydrocarbon propane to oxygenatescompounds
containing oxygencould be profitable. At the time, oxidation of
aliphatic hydrocarbons was primitive and expensive. Veatch's idea
was to use metal oxides to convert hydrocarbons to oxygenates. Funding
was approved for this effort beginning in 1953.
addition to starting new research, Sohio ventured into the petrochemical
business by building ammonia and nitrogen plants in Lima, Ohio,
and near Joplin, Missouri, to use by-products from its petroleum
refinery. It was a conservative move, but it encouraged Sohio to
view chemicals as a commercial enterprisea venture that would lead
to remarkable success.
experiments in Veatch's research yielded no major developments,
and he was given a six-week deadline. The resulting crash program
succeeded when a test run was made on propylene over a modified
vanadium pentoxide oxidant, and the resultant odor was instantly
recognizable as acrolein. Veatch knew that one more oxidation step
would take acrolein to acrylic acid--an important, expensive, fast-growing
monomer. For the next two years, several researchers, including
Ernest C. Milberger, James L. Callahan, Robert W. Foreman, James
D. Idol, Jr., Evelyn Jonak, and Emily A. Ross, were involved in
this development effort.
1955 the team began testing oxidants as direct oxidation catalysts.
In an experiment designed by Jim Callahan and performed by Emily
Ross, bismuth phosphomolybdate produced acrolein in yields of 40
percent or more. This was a first-magnitude discovery: propylene
to acrolein in a single catalytic reaction step. Acrylic acid could
be made in a subsequent step. Callahan, Foreman, and Veatch secured
key patents on the bismuth phosphomolybdate catalyst, and from then
on, things were destined to happen fast.
Idol suggested acrylonitrile as a derivative of acrylic acid and
successfully carried out catalytic conversion of the ammonium salt
of acrylic acid. Next, acrylonitrile was made by feeding acrolein,
ammonia, and air over the catalyst that produced acrylic acid from
acrolein. This success suggested that acrylonitrile might be made
directly from propylene by carrying out the entire reaction in a
single step with bismuth phosphomolybdate. The experiment, designed
by Idol and performed by Evelyn Jonak in March 1957, resulted in
ammoxidation, a process that produced acrylonitrile in about 50
percent yield with acetonitrile and hydrogen cyanide as co-products.
the capacity to make acrolein, acrylic acid, and acrylonitrile by
efficient, revolutionary new processes, Veatch pressed for a strong
development and commercialization effort. The Patents and Licensing
Department went to work on securing an iron-clad patent position.
Because manufacturing both acrylic acid and acrylonitrile proved
to be too ambitious, acrylonitrile production became the priority.
process economics for acrylonitrile were so positive that the decision
was made to proceed with commercialization even though early market
development efforts were discouraging. Major users were unsure that
Sohio acrylonitrile would satisfy their needs. One major chemical
company declined an opportunity for a joint venture. Another company
announced plans for a new 100-million-pound-per-year acrylonitrile
plant based on the old acetylene technology, at a cost of $100 million.
Sohio commissioned the design of a detailed acrylonitrile plant.
A pilot plant was constructed under the direction of Gordon G. Cross
at Sohio's new laboratory in Warrensville Heights, a Cleveland suburb,
where Ernie Milberger was instrumental in designing large laboratory-scale
reactors and obtaining process design and development data from
a bold move, it was decided to design the commercial plant on the
basis of bench-scale laboratory development data rather than wait
for pilot plant results. The time gained by eliminating this stage
of development offset the added risk. Milberger's bench-scale unit,
which required about four pounds of catalyst, generated the key
data for the design of commercial reactors holding 40 tons.
early 1958, the commercial design was going forward under the direction
of Edward F. Morrill; a pilot plant was in operation; the catalyst
was in final development by Callahan and his team with provisions
for large-scale manufacture; and advancement work on reactor operation,
product purification, and waste disposal was being coordinated.
A key innovation was the successful development of a fluidized bed
catalyst to allow for removal of the heat produced by the ammoxidation
mid-winter 1959-60, the Lima, Ohio, plant, which cost $10 million
to build, was complete. In less than four years since the discovery
of bismuth phosphomolybdate as the direct propylene oxidation catalyst
and the discovery of propylene ammoxidation, a full-scale commercial
plant designed to produce 47.5 million pounds of acrylonitrile per
year was ready to go.
was but one challenge left -- an economic one. Soon after Sohio's entry,
a major manufacturer cut its price in half. Sohio met the lower
price and still managed to make a profit. The competitor scrapped
its own expansion plans and took a license from Sohio. Other acrylonitrile
producers soon became licensees of the Sohio process, and within
a few years, acetylene-based acrylonitrile production had been replaced
by the Sohio process.
gain a larger share of the overall market, Sohio decided to promote
the licensing of the process rather than keep the manufacturing
to itself. Sohio's license to The People's Republic of China in
1973 was the first transaction by an American company after China
opened its doors to U.S. investment. Today, following Sohio's lead,
BP has licensed 42 companies to produce acrylonitrile in 77 plants
in 21 countries. Annual worldwide production of acrylonitrile has
grown from 260 million pounds in 1960 to more than 9 billion pounds
1960 BP Chemicals has developed and commercialized seven improved
catalyst formulations, most of them based on the original bismuth
phosphomolybdate catalyst. BP's current research focuses on further
improvements to the Sohio Acrylonitrile Process and on new technology
using the less expensive propane as feedstock.