废旧锌锰电池生物淋滤-水热法制备纳米锰锌铁氧体

以氧化硫硫杆菌(A.thiooxidans)和氧化亚铁钩端螺旋菌(L.ferrooxidans)为混合淋滤菌株对废旧锌锰电池进行了生物浸提,并以获取的淋滤液为前驱体,采用水热法制备出系列锰锌铁氧体软磁材料(Mn_(1-x)Zn_xFe_2O_4,x=0.2~0.8);结合X射线衍射(XRD)、扫描电镜-能谱(SEMEDX)、振动样品磁强计(VSM)、透射电镜(TEM)、红外光谱(FT-IR)、热重-差热分析(TG-DTA)等表征手段对制备材料的结构、形貌、磁学性能和稳定性进行分析.结果表明,在5%固液比(质量体积比,5 g/100 mL,以下均表述为"5%固液比")下,经过5 d的外源酸调控生物浸提,分别获得了84.5%、63.2%的Zn、Mn浸出效率;当Zn∶Mn∶Fe=0.4∶0.6∶2.0(物质的量比,即x=0.4)时,制备的纳米级Mn_(0.6)Zn_(0.4)Fe_2O_4性能最优,属纯相的立方尖晶石结构,颗粒分布均匀,饱和磁化强度(M_s)、剩余磁化强度(M_r)和矫顽力(H_c)分别为68.9 emu·g~(-1)、4.7 emu·g~(-1)和53.6 Oe,具有热稳定性和耐酸碱性,有望成为一种新型的水处理磁性材料.

Preparation of Mn-Zn ferrite from spent Zn-Mn batteries using bioleaching liquor as precursor

A.thiooxidans and L. ferriphilumand were used for bioleaching Zn/Mn from the spent Zn-Mn batteries electrode materials, and then the series of Mn-Zn ferritet soft materials (Mn_1-xZn_xFe₂O₄,x=0.2~0.8) were prepared by using hydrothermal synthesis method through bioleaching leachate as a precursor. In addition, the structure, morphology, magnetic properties and stability of the products were characterized by using XRD,SEM-EDX, VSM, TEM, FT-IR and TG-DTA. Experimental results show that the release efficiency were 84.5% for Zn and 63.2% for Mn under the condition of 5% solid content and 5-day exogenous acid to regulate bioleaching. The results indicate that Mn_0.6Zn_0.4Fe₂O₄ nanoparticle had a good magnetic separation property, thermal stability and higher acid-basic resistance. The prepared nanoparticles subordinated to pure cubic spinel structure with homogeneous particulate distribution,and its saturation magnetization, remanent magnetization and coercivity were 68.9 emu·g^-1, 4.7 emu·g^-1 and 53.6 Oe, respectively. It is expected to be a new magnetic material for water treatment.