Characterization of spent zinc–carbon and alkaline batteries by SEM-EDS, TGA/DTA and XRPD analysis

The aim of this paper is to characterize spent zinc–carbon and alkaline batteries. Characterization is essential to any process devoted to recovering the valuable materials contained in the batteries. In particular, the status of zinc and manganese has been established to permit treating only the zinc and manganese-bearing components in a recovery process, thus using smaller equipments and reducing both the material to treat and the energy consumption. At present, in fact, industrial processes treat the spent batteries as a bulk, only performing a preliminary separation with physical methods followed by a pyro- or hydrometallurgical process to recover zinc and manganese. Characterization has been carried out by chemical analysis, TGA/DTA analysis, XRPD and SEM analysis after having dismantled the batteries into the single components. Zinc and manganese are well separated in alkaline batteries while in zinc–carbon batteries the two metals are mixed, thus rendering difficult a preliminary separation by picking up the components containing the two metals separately.

► We characterized spent zinc–carbon and alkaline batteries. ► Location of Mn and Zn in the spent batteries was determined. ► Zn and Mn are intimately mixed in the cathode of the zinc–carbon batteries. ► Zn and Mn are separately present in the anode and in the cathode of spent alkaline batteries respectively.