Early career

While studying in Berlin, he also worked on Geiger counter instrumentation and cosmic ray measurements at the Institute of Cosmic Radiation Research. After graduating in the US, he carried out further work in these fields at the Bartol Research Foundation of the Franklin Institute and was seconded to MIT helping to develop a long-range radio navigation system, LORAN. He also taught part-time at Swarthmore College.^[3]

Mobil

In 1946 he joined Mobil as a Research Assistant, turning his attention to diffusion and catalysis, eventually rising to become Manager of the Central Research Laboratory, and staying there until his retirement in 1984.^[1][3] It was there that he carried out the work which made him most famous, the development of shape-selective catalysts which revolutionized many petroleum refining and chemical processes.^[2] A 1960 paper, "Intracrystalline and Molecular-Shape-Selective Catalysis by Zeolite Salts",^[4] coauthored with Vince Frilette, a Mobil colleague, became the foundation of shape-selective catalysis (which accelerated certain chemical reactions, but only for molecules of particular shape) and one of his most widely cited papers. Processes based on this and subsequent work were first commercialized in the early 1960s.^[1]

The company permitted him a sabbatical period from 1964 to 1966 at ETH Zurich, where he earned a doctorate setting the foundation for some of the fundamental laws of diffusion in dyeing.^[1]

Academic career

From 1974 to 1976 he was a visiting professor at Princeton University. From 1983 he was a distinguished professor of chemical and bio-engineering at the University of Pennsylvania. From 1993 he was an adjunct professor in chemical engineering at Pennsylvania State University.^[3] In this period he applied chemical and physical principles to biomedical research, including work with Madeleine M. Joullié on the synthesis of a molecule equivalent to heparin which avoided the dangerous side-effects of the natural molecule.^[1]