Optimization of powder production and properties to increase the kinetics of cobalt cementation at CEZinc

在CEZ的净化过程中，锌颗粒被添加到料液中，以在电积之前去除铜、镉和钴等杂质。杂质的去除受到锌颗粒上胶合作用的影响。胶结是一种多相反应，有利于获得大表面积的锌颗粒。因此，锌颗粒比表面积越大，胶结动力学越快。同样，在锌颗粒中添加铅也改善了胶结动力学。因此，将开展工作，以确定最佳的粉末特性方面的铅预合金化和粒度分布，以最大限度地提高胶结动力学。这项工作将主要在拉瓦尔大学的粉末冶金实验室进行，该实验室配备了水雾化系统。还计划进行技术转让活动，以复制该工厂的最佳实验室结果。

During the purification process at CEZ, zinc particles are added to the feed solution to remove impurities such as copper, cadmium and cobalt prior to electrowinning. The removal of impurities is affected by cementation onto zinc particles. Cementation is a heterogeneous reaction favoured by the availability of large surface area of the zinc particles. Hence, the larger surface area of the zinc particles the faster the kinetics of cementation. Similarly, it has been shown that additions of lead to the zinc particles also improves the kinetics of cementation. Thus, work will be carried out to identify the optimum powder characteristics in terms of lead pre-alloying and size distribution to maximize the kinetics of cementation. This work will be performed mostly at the Powder Metallurgy Laboratory of Université Laval that is equipped with a water atomization system. Technology transfer activities are also planned to replicate the best laboratory results in the plant.