Fig. 3: Mechanism of the improved REE extractability by the electrothermal activation.
From: Sustainable rare earth extraction from phytomining by rapid electrothermal calcination
a XRD patterns of Raw BO, Activated BO, and Calcinated BO. The CaCO3 with reference PDF (CaCO3, #99-0022) and C with reference PDF (C, #26-1080) were shown. b SEM image of Activated BO. Scale bar, 10 μm. c EDS of Raw BO, Activated BO, and Calcinated BO. d XPS full spectra of Raw BO, Activated BO, and Calcinated BO. e XPS fine spectra of La 3d5/2 in Raw BO and Activated BO. La was not detected in Raw BO. Note that the La at 838.55 eV is the shake-up satellite. f XPS fine spectrum of Nd 3d5/2 in Raw BO and Activated BO. The O Auger KLL peak is labeled. g Content of six REE forms in Raw BO, Activated BO, and Calcinated BO. h Percentage of six REE forms of La in Raw BO, Activated BO, and Calcinated BO. i Changes in the percentage of different forms of REE in Raw BO and Activated BO.
