Recovery of rare earth elements from Dicranopteris dichotoma by an enhanced ion exchange leaching process

An original process aiming at selectively extracting REEs from the hyperaccumulator plant Dicranopteris dichotoma was developed. This process relies on an enhanced ion exchange leaching step carried out in 0.5 M nitric acid solution. Once ion exchange resin is transferred into a column, REEs purification is carried out by percolating successively three solutions through resin bed: two washing steps, with water and 0.75 M nitric acid to remove competing ions and one elution step using 3 M nitric acid. These operating conditions led to 81.4% REEs purity and 78% recovery.