Song Wenchen, Chen Xu, Jia Yanhong, Yang Mingshuai, Ye Guoan, Zhu Fuxing
Department of Radiochemistry, China Institute of Atomic Energy, Beijing 102413, China.
Panxi Institute of Vanadium and Titanium Inspection and Testing, Panzhihua 617000, China.
Materials (Basel). 2025 Jun 4;18(11):2634. doi: 10.3390/ma18112634.
Zirconium, a critical rare metal with exceptional corrosion resistance and nuclear applications, is conventionally produced via the energy-intensive Kroll process. The electrolysis of ZrCO soluble anodes has been extensively investigated due to its advantages in having a short process flow and resulting in high-quality products. In particular, during the electrolysis of zirconium oxycarbide with a C:O molar ratio of 1:1, gaseous CO can be released, and no residual anodes are generated, which is extremely appealing. In this regard, this paper explores the feasibility of preparing zirconium metal through high-temperature vacuum reduction to produce zirconium oxycarbide using ZrO as the raw material, followed by direct molten-salt electrolysis. Firstly, the reduction products were characterized using an X-ray diffractometer (XRD) and a scanning electron microscope (SEM). The results showed that under a vacuum of <10 Pa at 1750 °C, the reduction products mainly consisted of ZrCO and a small amount of ZrO, and they exhibited good electrical conductivity (0.0169 Ω·cm). Subsequently, the cyclic voltammetry test results of the reduction products revealed the reversible redox behavior of ZrCO. There were characteristic oxidation peaks at -0.53 V and -0.01 V (vs. Pt), corresponding to the formation of Zr and Zr, respectively, and a reduction peak at -1.51 V, indicating the conversion from Zr to Zr. Finally, -zirconium metal with a purity of 99.2 ± 0.3 wt.% was obtained through potentiostatic electrolysis, and its quality met the R60704 grade specified in ASTM B551-12 (2021). This study offers a novel approach for the short-flow preparation of zirconium metal, which is conducive to expanding its applications.
锆是一种具有优异耐腐蚀性和核应用价值的关键稀有金属，传统上通过能源密集型的克罗尔法生产。ZrCO可溶性阳极的电解因其工艺流程短且能生产高质量产品的优点而受到广泛研究。特别是，在碳化氧锆的电解过程中，当碳与氧的摩尔比为1:1时，可以释放出气态CO，并且不会产生残留阳极，这极具吸引力。在这方面，本文探索了以ZrO为原料，通过高温真空还原制备碳化氧锆，然后进行直接熔盐电解来制备锆金属的可行性。首先，使用X射线衍射仪（XRD）和扫描电子显微镜（SEM）对还原产物进行了表征。结果表明，在1750℃、真空度<10 Pa的条件下，还原产物主要由ZrCO和少量ZrO组成，并且具有良好的导电性（0.0169Ω·cm）。随后，还原产物的循环伏安测试结果揭示了ZrCO的可逆氧化还原行为。在-0.53 V和-0.01 V（相对于Pt）处有特征氧化峰，分别对应于Zr和Zr的形成，在-1.51 V处有一个还原峰，表明从Zr到Zr的转化。最后，通过恒电位电解获得了纯度为99.2±0.3 wt.%的锆金属，其质量符合ASTM B551-12（2021）规定的R60704等级。本研究为锆金属的短流程制备提供了一种新方法，有利于拓展其应用。
