
Wentorf, a modern-day alchemist
The Hindu
On February 12, 1957, General Electric Company announced that Robert H. Wentorf had successfully synthesised cubic boron nitride, or borazon. He achieved it by using the same general technique that had allowed him, along with others, to turn lowly graphite into diamonds two years earlier. Join A.S.Ganesh as he walks you through Wentorf’s life…
Do you know what alchemy is? An ancient form of chemistry and speculative philosophy, the art of alchemy was handed down through the ages from Egypt and Arabia to Greece and Rome. Alchemists had three main aims: to find the Stone of Knowledge or the Philosophers’ Stone, to discover the means for eternal youth and health, and to discover the transmutation of metals.
This third and final aim has largely appealed to the popular imagination as it allows the practitioner to transmute base metals, or any common substance, into precious ones. American chemist Robert H. Wentorf can be said to be a modern-day alchemist as he succeeded in converting graphite into diamonds.
Born in 1926 in West Bend, a city in Wisconsin, U.S., Wentorf went to the University of Wisconsin, where he graduated in chemical engineering in 1948. After completing his Ph.D. in physical chemistry in the same university, Wentorf joined General Electric (GE) Research Laboratory in 1951.
Ever since it was known that diamonds were a form of carbon, scientists had tried, without success, to make artificial diamonds. Success was finally achieved after two centuries of trying when Wentorf, along with Tracy Hall, Francis Bundy, and Herbert Strong, synthesised diamonds as part of a top-secret Project Superpressure.
The four researchers were aware that graphite, a pure carbon substance, must be key to creating human-made diamonds. When they discovered that strong bonding made graphite resistant to change, they employed iron sulphide as a catalyst to weaken the carbon bonds.
When the graphite thus weakened was subjected to extremely high pressures, the scientists were able to artificially synthesise diamond for the first time in December 1954. GE Research Laboratory made the results of their project public in 1955.
By using the same general techniques of combining tremendous pressures with high temperatures, Wentorf succeeded again in creating a material not found in nature. GE announced on February 12, 1957 that Wentorf had synthesised cubic boron nitride, which was given the trade name borazon.