铝电解NiFe2O4基金属陶瓷惰性阳极电解过程表面结构特征演变规律

项目名称： 铝电解NiFe2O4基金属陶瓷惰性阳极电解过程表面结构特征演变规律

项目编号： No.51474238

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 矿业工程

项目作者： 田忠良

作者单位： 中南大学

项目金额： 83万元

中文摘要： 基于惰性电极铝电解新工艺因可彻底消除温室气体排放而备受关注。惰性阳极腐蚀速率是其成功的关键。申请者在参与20kA惰性电极试验时发现与以往对NiFe2O4基金属陶瓷腐蚀认识不一致的现象：阳极表面在电解质、或新生态氧、或两者共同作用下发生物相结构转变，而原位生成具有更强耐腐蚀性能的富铝致密层，有效减缓阳极腐蚀。 本项目拟开展铝电解NiFe2O4基金属陶瓷惰性阳极电解过程表面结构特征演变规律的研究，揭示极化状态下NiFe2O4基金属陶瓷阳极表面新生物相的生成与腐蚀机理，阐明由新生物相形成的致密耐蚀层原位生长与腐蚀过程的动力学特征，获得阳极表面新生物相形成的致密耐蚀层持续保持的调控方法，为创建基于阳极表面致密耐蚀层原位形成的腐蚀抑制技术提供理论基础。该项目的研究，也可为其他复杂多变服役环境下，材料腐蚀机理的认识以及防腐蚀技术的开发提供借鉴。

中文关键词： 铝电解；金属陶瓷；惰性阳极；表面结构；演变

英文摘要： The new aluminum reduction technology based on inert electrode was received much concern because of the green-house gas elimination. The key to realize this technique is the corrosion rate of inert anode during electrolysis. During a 20kA pilot testing of this technology, a new phenomenon, which is different from previous understanding about the corrosion mechanism of NiFe2O4 based cermet inert anode,was observed.That is to say, because of the effect of the electrolyte, or the nascent state oxygen, or the both together, the phase at the surface of inert anode would transform and form an aluminum-rich compact layer, which the anti-corrosion performance is stronger than its matrix. And at the same time, the compact layer could decrease effectively the corrosion rate of the inert anode. This project would carry out the research on the evolution of the surface structure of NiFe2O4 based cermet inert anode for aluminium reduction during electrolysis porcess. The mechanisms of the formation and the erosion of new produced phase at the surface of NiFe2O4 based cermet inert anode polarized are discovered. And the kinetic characeteristics of the growth and the corrosion in-situ of the compact anti-corrosion layer, which is made of new producted phase, are also illuminated. And then, a controlling method would be founded, which would realize the continuous maintain of this compact anti-corrosion layer. Thus, a theoretical basis of anti-corrosion techology, which bases on the formation of the compact anti-corrosion layer in-situ at the material surface, would be provided. Simultaneously, a referance would also be provided for the development of material anti-corrosion technology under various changeable service condition.

英文关键词： Aluminium Reduction;Cermet;Inert Anode;Surface Structure;Evolution