Mn-Zn nano-crystalline ferrites synthesized from spent Zn-C batteries using novel gelatin method

A novel recycling route using acid leaching, reduction and gelatin method was applied to recycle spent Zn-C batteries into more valuable magnetic nano-crystalline ferrites; Mn1-xZnxFe2O4 (with x=0.2-0.8). The cost of this recycling technology has economical advantages, which holds promising industrial application products. Dried gel thermal decomposition process was monitored by simultaneous differential thermal analysis-thermogravimetry-differential scanning calorimetry. Phase composition, morphological and magnetic properties of the as-prepared precursors were characterized using X-ray powder diffraction, transmission electron microscopy, Fourier transform infrared and vibrating sample magnetometer. Single-phase agglomerated cubic ferrites with crystal sizes in the range 21-41 nm were detected. The obtained magnetization values are significantly lower than that of the bulk ferrite and showed a gradual increase with increasing Zn-substitution with an obvious decrease at x=0.6. On the other hand, a reverse trend was exhibited by coercivity. The effect of Zn-substitution on both structural and magnetic properties, paved the way to suggest proper cation distributions for the investigated system. (C) 2012 Elsevier B.V. All rights reserved.