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A New Way to Extract Uranium

A new technique to extract uranium from brannerite, which mining companies have long-viewed as a waste product, could boost uranium extraction by up to 15%, which equates to 1000 tonnes or approximately $108 million per annum.

Murdoch University PhD candidate Rorie Gilligan says the discovery started from simple curiosity about where uranium volume was lost in extraction.

“In recent decades, the assumption has been that brannerite can’t be processed,” Gilligan says. “I dug into the archives and ended up finding a number of basically forgotten papers from the 1950s and 60s exploring brannerite extraction, which gave us a starting point for testing our own ideas in the lab.”

Gilligan has been running trials on pure brannerite specimens and on mixed mineral conditions that are likely to occur in natural deposits. While conventional wisdom was that increasing the acid or alkaline environment would increase the rate of leaching of hard-to-extract minerals, this wasn’t the case with brannerite.

“By gaining a better understanding of the chemical processes involved in leaching brannerite, we’ve found a mechanism that works under relatively mild conditions without the need for high acid concentrations or extreme heats,” Gilligan says.

Dr Aleks Nikoloski, who co-authored the paper published in Science Direct, was stunned by the initial data. “We were getting an extraction rate of 80–90% for a mineral that was supposed to be refractory,” he said. “I asked for the sample to be re-examined to make sure it was brannerite.”