Abstract: An example of a method and apparatus to remove a waste element from a brine solution is provided. The method involves receiving the brine solution comprising dissolved lithium and a waste element. The method further involves pumping the brine solution into a cavitation chamber. In addition, the method involves adding a combining ion to the brine solution. The method involves reducing a pressure of the brine solution in the cavitation chamber as the brine solution moves away from an inlet. The pressure is reduced to below a fluid vapor pressure of the brine solution to create micro-bubbles. Furthermore, the method involves collapsing the micro-bubbles to generate a localized energy release to accelerate the formation of a waste precipitate to provide a mixture of the brine solution and the waste precipitate. The method involves filtering the waste precipitate to remove the waste element from the mixture.