- Born:
- May 18, 1889, Beaver Falls, Pennsylvania, U.S.
- Died:
- November 2, 1944, Worthington, Ohio (aged 55)
- Subjects Of Study:
- dichlorodifluoromethane
- tetraethyl lead
- antiknock agent
- knocking
- refrigerant
Thomas Midgley, Jr.
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Who was Thomas Midgley, Jr.?
Thomas Midgley, Jr. (1889–1944) was an American engineer and chemist known for his work on internal combustion and developing chemical compounds for use in gasoline and refrigeration.
Midgley's research on engine knock led to the discovery of tetraethyl lead (TEL) as an antiknock additive for gasoline. Although the toxic effects of lead were known, Midgley promoted leaded gasoline, also developing a method to extract bromine from seawater to expel lead from engines. Lead poisoning forced Midgley to take a break from his research at one point. Concerns over lead poisoning and its interference with pollution-control devices led to the phasing out of leaded gasoline, beginning in the 1970s.
Midgley also discovered dichlorodifluoromethane, commercialized as Freon-12, as a safe refrigerant. Chlorofluorocarbons (CFCs) like Freon-12 were later found to threaten the environment by depleting the ozone layer.
Midgley contracted polio in 1940 and lost the use of his legs. He later died by strangulation in a hoist mechanism that he invented to help him in and out of bed.
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What was Thomas Midgley, Jr.'s profession?
Thomas Midgley, Jr. was an American engineer and chemist. After graduating from Cornell University with a degree in mechanical engineering in 1911, he worked as a draftsman and designer. Later, he joined the Dayton Engineering Laboratories Company (Delco) and then the Dayton Metals Products Company, a research arm of General Motors Corporation in 1919.
Midgley's research led to the discovery of tetraethyl lead as an antiknock additive for gasoline. He also found that dichlorodifluoromethane (Freon-12) could be used as a safe refrigerant. From 1940 to 1944, he served as a director and vice president of the Ohio State University Research Foundation.
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What is Thomas Midgley, Jr. famous for inventing?
Thomas Midgley, Jr. was an American engineer and chemist notable for two significant inventions. In the 1920s, he discovered tetraethyl lead (TEL) as an antiknock additive for gasoline to improve engine performance. Later, in the 1930s, he developed dichlorodifluoromethane (Freon-12), a non-toxic, nonflammable refrigerant gas for refrigerators and air conditioners. Though commercially successful, both inventions were later recognized as major environmental hazards, contributing to lead poisoning and ozone depletion.
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How did leaded gasoline, invented by Midgley, impact the world?
Thomas Midgley, Jr. discovered tetraethyl lead (TEL) as an antiknock additive for gasoline, which significantly improved engine performance starting in the 1920s. Known as leaded gasoline, it became standard after World War II but was later phased out due to lead causing lead poisoning and interfering with pollution-control devices in automobiles.
Despite initial approval and Midgley's promotion, studies revealed the dangers of lead accumulation and its impact on public health, leading to bans in the U.S., Canada, and the European Union.
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What are chlorofluorocarbons (CFCs), and how was Midgley involved with them?
Chlorofluorocarbons (CFCs) are organic compounds containing carbon, fluorine, and chlorine, widely used as refrigerants, aerosol propellants, solvents, and foam-blowing agents due to their nontoxic and nonflammable properties. However, CFCs pose a serious environmental threat, as they accumulate in the stratosphere and deplete the ozone layer, which protects life on Earth from harmful UV radiation.
Thomas Midgley, Jr. discovered that dichlorodifluoromethane (Freon-12, a type of CFC) could be used as a safe refrigerant. In 1930, he was tasked to find a non-toxic, nonflammable, and odorless refrigerant, leading to the commercial production of Freon-12 by Kinetic Chemicals, where Midgley served as a director.
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How have Thomas Midgley, Jr.’s inventions affected the environment and public health?
Thomas Midgley Jr.'s inventions significantly impacted the environment and public health. His discovery of tetraethyl lead (TEL) as an antiknock additive for gasoline led to widespread use of leaded gasoline, which caused lead poisoning and the accumulation of lead in the environment. The toxic effects of lead exposure include neurological damage, especially in children.
Midgley also discovered dichlorodifluoromethane (Freon-12) as a safe refrigerant. However, this and other chlorofluorocarbons (CFCs) were later found to deplete the ozone layer, increasing the risk of skin cancer and genetic damage. Although CFCs have been phased out, their impact on the ozone layer persists.
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Thomas Midgley, Jr. (born May 18, 1889, Beaver Falls, Pennsylvania, U.S.—died November 2, 1944, Worthington, Ohio) was an American engineer and chemist who discovered the effectiveness of tetraethyl lead as an antiknock additive for gasoline. He also found that dichlorodifluoromethane (a type of fluorocarbon commercialized under the trade name Freon-12) could be used as a safe refrigerant.
The son of an immigrant inventor from London, Midgley grew up in Pennsylvania, New Jersey, and Columbus, Ohio. After graduating from Cornell University with a degree in mechanical engineering (1911), he worked in Dayton, Ohio, as a draftsman and designer at the National Cash Register Company (where only a few years earlier Charles F. Kettering had developed the first electric cash register) and then at his father’s automobile tire factory. In 1916 he went to work for Kettering, first in the research staff of the Dayton Engineering Laboratories Company (Delco) and then for the Dayton Metals Products Company, and he stayed with the latter company after it became a research arm of the General Motors Corporation in 1919.
Midgley’s research on the problem of engine knock made him a pioneer in the study of internal combustion. Starting his research in 1916, he quickly found that engine knock in the new high-compression gasoline engines for automobiles was caused not by the ignition system but by the fuel mixture, which did not burn evenly. Discovering by chance that a liquid compound called ethyl iodide reduced knock, he dedicated himself to finding an effective additive that would improve the combustion of gasoline and could be produced economically using the technology of the time. His efforts were interrupted by research for the U.S. war effort during World War I, when he worked on developing control systems for a propeller-driven “aerial torpedo” and on producing high-performance airplane fuel. At war’s end he resumed his search for a gasoline additive, systematically working his way through promising element groups in the periodic table, and in 1921 he and his team found that minute amounts of tetraethyl lead completely eliminated engine knock. Finding that the lead formed deposits in the engine, Midgley settled on using ethylene bromide as a compound that would cause the lead to be completely expelled in the engine’s exhaust. This led to the problem of finding an economical source of bromine, and here Midgley is credited with developing a method for extracting the element from seawater.
The toxic effects of lead were well known at the time, and at one point Midgley had to withdraw from his research for a short time to recover from lead poisoning. Still, he never wavered in his conviction that tetraethyl lead could be produced safely and that the small amounts of lead particulates expelled in engine exhaust would not pose a threat to public health. As vice president of the Ethyl Gasoline Corporation from 1923, he promoted the new leaded gasoline to a skeptical public and regulators. From 1933 he was also vice president of the Ethyl-Dow Chemical Company, which produced bromine from seawater.
In 1930 Midgley was directed to find an odour-free, nontoxic, and nonflammable refrigerant gas that could be used in residential refrigerators and air conditioners. Within three days he settled on dichlorodifluoromethane, which was soon commercially produced as Freon-12 by Kinetic Chemicals, Inc., for which Midgley served as director. From 1940 to 1944 he was a director and vice president of the Ohio State University Research Foundation. For his chemical discoveries he received many honours, including four medals from the American Chemical Society and election to the National Academy of Sciences.
During World War II Midgley served as head of one branch of the National Defense Research Committee; he also conducted extensive research on the composition of natural and synthetic rubbers. In 1940 he was struck by polio. Though he lost the use of his legs, he continued to work. He died by strangulation in a hoist mechanism that he had invented to help him in and out of his bed.