173625.fig.007
Figure 7: X-ray diffraction (XRD) spectra (for the range of 10–90° 2θ) recorded for the mine water batch systems containing as-formed (LHS) and vacuum annealed (RHS) nano-Fe3O4 extracted at reaction times of 1 h, 4 h, 24 h, 7 d, and 84 d.