Preparation of zinc nano structured particles from spent zinc manganese batteries by vacuum separation and inert gas condensation

摘要

Vacuum separation and inert gas condensation were adopted to recycle zinc and prepare zinc nanoparticles from spent zinc manganese batteries in this paper. As a result of the relatively high pressure, zinc can be easily separated from the other metals in zinc manganese batteries by vacuum evaporation with a high separation efficiency. Simultaneously, morphology controlled zinc nano-particles were prepared by inert gas condensation. The results showed that inert gas pressure, heating and condensing temperature, condensation distance away from the evaporation source, and condensation substrate were the significant factors on nano-particles preparation. Higher inert gas pressure was beneficial for preparing inerratic nano-particles because of the diffusing effect. At higher heating temperature and lower condensing temperature, more inerratic nano-particles could be prepared. With more collisions and cementations, the particles became irregular at the places far away from the heater. It was also observed that nano structured particles with different morphologies including hexagonal prisms, fibriform and sheet shapes were prepared on different substrates. Uniform zinc nano hexagonal prisms with the diameter of 100-300 nm and the purity of more than 99 wt.% were successfully prepared on the quartz substrate under the optimized conditions as follows: 1000 Pa inert pressure, 1073 K heating temperature, lower than 473 K condensing temperature and 10-30 cm condensation distance. The zinc separation efficiency can attain to 99.68%. This work provided an efficient and promising way for recycling zinc with high purity and high added values from spent zinc manganese batteries. (C) 2015 Elsevier B.V. All rights reserved.