Menachem Elimelech has made significant contributions to the field of water research, including a desalination process involving forward osmosis. Photo: Michael Marsland, Yale University

Menachem Elimelech has dedicated his life to making the world's water safer. For the past 16 years, he has conducted research on colloidal particles and microbial pathogens (viruses and Cryptosporidium) in water, furthering our understanding of physical and chemical processes to improve the quality of drinking water.

“It is now widely accepted that water scarcity and the lack of safe drinking water are serious challenges,” said Elimelech. “Research on removal of contaminants from water, and on the use of membrane processes to extract water from seawater and domestic wastewater, is crucial in this respect.”

The National Water Research Institute awarded Elimelech its 2005 Athalie Richardson Irvine Clarke Prize for excellence in water research. Among the groundbreaking achievements he has been lauded for is a desalination process called ammonia-carbon dioxide forward osmosis, anticipated to be more cost-effective and efficient than traditional desalination.

“In the common process for seawater desalination, called reverse osmosis, we apply very high hydraulic pressure across a semi-permeable membrane that pushes water molecules through the membrane and retains the salt,” said Elimelech. “In our forward osmosis process, we do not apply hydraulic pressure. Instead, we use ammonia-carbon dioxide draw solution on one side of a specialized forward osmosis membrane. This draw solution generates very high osmotic pressure that causes pure water to transport across the membrane from the seawater. We then separate the fresh water from the draw solution.

“I am proud of the research we have carried out on various aspects of water science and technology, and of the new generations of scientists and engineers that I educated during my academic career,” he said.