Gregory R. Choppin

Gregory R. Choppin was an American chemist renowned for his pioneering research in actinide and lanthanide chemistry. His extensive career, primarily at Florida State University, fundamentally advanced the understanding of f-element behavior in aqueous solutions and separation science. Choppin's work had significant applications in nuclear fuel cycle management, environmental remediation, and medical radioisotope production. He was a prolific author, co-writing seminal textbooks and mentoring generations of scientists in radiochemistry.

Early life and education

Born in Los Angeles, he developed an early interest in science. He completed his undergraduate studies in chemistry at Loyola Marymount University in 1949. Choppin then pursued graduate work at the University of Texas at Austin, earning his Ph.D. in 1953 under the supervision of nuclear chemist John O. Rasmussen. His doctoral research involved investigating nuclear isomerism and laid the foundation for his lifelong focus on the chemistry of radioactive elements.

Career and research

Following his Ph.D., Choppin joined the prestigious Lawrence Berkeley National Laboratory, working alongside notable figures like Glenn T. Seaborg. In 1956, he moved to Florida State University, where he spent the remainder of his academic career, helping to build a world-renowned program in nuclear chemistry. His research elucidated the complex coordination chemistry and thermodynamic properties of lanthanide and actinide ions, particularly their behavior in solvent extraction processes. This work was critical for developing efficient methods to separate plutonium from spent nuclear reactor fuel and to isolate americium and curium for various applications. He also made significant contributions to understanding the environmental migration of radionuclides like neptunium and plutonium, informing waste disposal strategies. His authoritative textbooks, *Radiochemistry and Nuclear Methods of Analysis* and *Nuclear and Radiochemistry* (co-authored with Jan-Olov Liljenzin and Jan Rydberg), became standard references worldwide.

Honors and awards

Choppin received numerous accolades for his scientific contributions. He was awarded the prestigious American Chemical Society Award in Nuclear Chemistry in 1969 and the Glenn T. Seaborg Award for Nuclear Chemistry in 1985. His international recognition included the Alexander von Humboldt Senior U.S. Scientist Award and the AAAS Fellowship. He was also elected a fellow of the American Nuclear Society and served as a divisional chair for the American Chemical Society. In 1990, he was honored with the Florida State University Robert O. Lawton Distinguished Professor Award, the university's highest faculty honor.

Personal life and legacy

He was married to his wife, Mary, for over six decades. An avid outdoorsman, he enjoyed fly fishing and hiking. Choppin passed away in Tallahassee in 2023. His legacy endures through his foundational research, which continues to influence fields from nuclear forensics to the design of advanced fuel cycles. The generations of students and postdoctoral researchers he trained at Florida State University now hold prominent positions in national laboratories, academia, and industry, perpetuating his impact on the discipline of radiochemistry.

Category:American chemists Category:Nuclear chemists Category:Florida State University faculty Category:1927 births Category:2023 deaths