The reverse osmosis technology has proven to be the most advanced way for eliminating salt from saltwater and improving access to clean water. Other uses include wastewater treatment and energy generation.
In a new study, a group of academics show that the mainstream explanation for how reverse osmosis works, which has been accepted for more than five decades, is fundamentally incorrect.
During this procedure, the researchers propose an alternative theory. Aside from rectifying the record, these findings may lead to more successful applications of reverse osmosis. The findings of the study, led by Prof. Menachem Elimelech’s group, have been published in Science Advances.
Reverse osmosis, which was originally used in the 1960s, removes salt and pollutants from water by passing it through a semipermeable membrane that allows water to pass through while blocking contaminants.
Researchers used solution-diffusion theory to explain how it works in detail. This idea proposes that water molecules dissolve and diffuse through the membrane along a concentration gradient, moving from locations with high concentration to areas with less molecules.
Despite the fact that this idea has been generally accepted for over 50 years and is even taught in textbooks, Elimelech has long had reservations about it.
Now a team of researchers reveal in a new study that the standard explanation for how reverse osmosis works — one that has been accepted for more than five decades – is fundamentally wrong
“Some of the assumptions do not make any sense,” said Elimelech, the Sterling Professor of Chemical and Environmental Engineering.
For example, he claims that the theory is founded in part on the assumption that pressure across the membrane is constant. “Whenever you have water flowing through any porous material, there is always a pressure drop.”
Source: Yale Seas
