Professor Arup K. SenGupta delivered the inaugural plenary lecture at the International Ion Exchange Meeting (IEX’12) held earlier this month at Cambridge University in the United Kingdom. SenGupta’s lecture was based on a paper he co-authored with Michael German, a Ph.D. candidate in environmental engineering. SenGupta explained the use of the Donnan principle, the failure of charged particles to distribute evenly across the two sides of a nearby semi-permeable membrane, in developing new hybrid materials and processes. The hybrid anion exchanger (HAIX) material developed and patented by SenGupta’s group is now being used in six countries to remove trace amounts of arsenic and other contaminants from water, as well as being tested in Fukushima, Japan, to remove radioactive particles from the water. SenGupta has been a Lehigh professor for 27 years, and holds dual appointments in the department of civil and environmental engineering and the department of chemical engineering.