Kathleen C. Taylor

Kathleen C. Taylor

Kathleen C. Taylor. Courtesy Northwestern University Archives.

The Clean Air Act of 1970 demanded that automobile makers reduce tailpipe emissions by 90 percent. But how? Chemical engineer Kathleen C. Taylor (b. 1942) and other scientists developed catalytic converters, which use chemical reactions to turn noxious emissions into less harmful gases. Introduced in new cars by 1975, these devices reduced auto exhaust pollution by 95 percent.

Taylor earned a bachelor’s degree in chemistry in 1964 from Douglass College of New Jersey’s Rutgers University, and then a Ph.D. in physical chemistry from Northwestern University in 1968. She traveled to Scotland to do postdoctoral research at the University of Edinburgh before returning to the United States to work in industry.

In graduate school Taylor had done research on catalysts. When she went to work at General Motors in 1970, this research would prove to be very useful. The Clean Air Act of 1970 required, among other things, that car makers clean up the exhaust produced by their new vehicles. In those days, exhaust released from the tailpipe of a car was full of toxic compounds, like carbon monoxide and oxides of nitrogen. Some years earlier Eugene Houdry, a French scientist working in the United States, had invented early versions of a device called a catalytic converter that made auto exhaust much cleaner. Emission control occupied a large portion of Taylor’s research at General Motors.

In chemistry, a catalyst is a substance that increases the rate of a chemical reaction without being consumed in the reaction. A catalytic converter is a device located between a car’s engine and exhaust pipe. The converter is filled with tiny particles of the metals platinum and rhodium. These metals catalyze chemical reactions that turn toxic compounds in the exhaust into less toxic ones. One of the problems with the earliest catalytic converters was their tendency to convert nitric oxide into ammonia. Since ammonia is also toxic, this really did not help matters much. Taylor and her coworkers invented an improved catalytic converter that converted nitric oxide into nitrogen gas, which is not only nontoxic, but also makes up most of the air we breathe.

In the years after this invention, Taylor advanced to the position of director of the materials and processes laboratory at General Motors Research and Development. Now retired from General Motors, she maintains an active role as an adviser to the United States Department of Energy and Columbia University’s Center for Electron Transport in Molecular Nanostructures on a wide variety of new technologies designed to reduce environmental impacts.

Some of Taylor’s best early memories are of the “painting holidays” she and her mother used to take to Ireland, where they would paint that country’s scenic landscapes in watercolor. Today, in addition to her scientific work, she still enjoys watercolor painting.

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