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

Abstract : 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.