Fundamental study of an ambient temperature ferrite process in the treatment of acid mine drainage

The feasibility of making ferrite at ambient temperature from solutions of simulated acid mine drainage is explored. The X-ray diffraction and saturation magnetization of the precipitates obtained clearly show that the spinel ferrite can be made at ambient conditions and pH 9-11. The optimum molar ratio Fe3+ to Fe2+, a critical parameter for ferrite formation, is found to be 1.75. The effect of [Zn2+] and [Ca2+] in solution on ferrite formation was investigated. The former has no effect on the magnetic properties of ferrite, but the saturation magnetization of the ferrite decreases with an increase of [Ca2+]. The results suggest that an ambient temperature ferrite process for acid mine drainage is worthy of further investigation.