Synthesis and Characterization of Mn-ZnO Recovered from Spent Batteries, its Possible Use in Poly(Ethylene Terephthalate) PET Glycolysis

Mn doped ZnO powders were obtained by mechanical milling, a simple and economic method, using recovered oxides from batteries waste as starting materials. Structural and morphological properties of the solids were investigated by powder X-ray diffraction and scanning and transmission electron microscopy. A red shift in the absorption spectra from DRS-UV-visible spectroscopy due to Mn doping in ZnO was observed. The optical results confirm our previous theoretical outcomes that Mn doping gives place to new electronic states in the band gap. These findings reveal the important role played by the interaction between doped atoms and vacancies on the interesting properties observed. The catalytic activity of the solids in the glycolysis of PET was evaluated and the results showed a yield of 80% towards the formation of BHET for powders with highest Mn concentration and longest milling time. It is possible to obtain new materials from waste that allow to close the life cycle of batteries and plastic bottle waste.