Preparation And Research On Nano-NiO-Cu-NiFe₂O₄ Inert Anode

Inert anode for aluminum electrolysis can greatly reduce production cost, cut down energy consumption, increase the production capacity and is environmentally friendly, its development and application will bring about a revolution in aluminum industry. At present, one of the priority resolve problem on the basis of study is the project technique problem, such as to solve large-scale production and machining etc. This thesis mainly focuses on metal based inert anodes for aluminum electrolysis. Some novel materials as inert anodes were developed and investigated for aluminum electrolysis .Tracking the recently research development, with the spinel NiFe₂O₄ good corrosion and excellent Cu conductivity and mechanical, the first application of nano-NiO to improve the brittleness of the cermets.NiFe₂O₄-based cermets were prepared by doping the NiFe₂O₄ ceramic matrix with the mixed powders of Cu as the electrical conducting metallic elements and different quality nano-NiO had been added, these samples was divided into five groups, each with two samples. They were sintered at 1000℃-1200℃. Characterization techniques such as XRD, optical microscopy, and experimental apparatuses such as high temperature electric resistance determination equipment and simulation of corrosion were adopted to study the effects of nano-NiO content in ceramic phase of cermets and Cu on the corrosion behavior, density, and electric conductivity of cermets, moreover, the corrosion and electric conductivity mechanisms were also discussed .The main conclusions and findings can be summarized as follows:1.The cermets of NiO-Cu-NiFe₂O₄ were prepared with Fe₂O₃ . NiO , Cu and nano-NiO ,sintered at 1000℃-1200℃for 6 hours in the air . The silver gray sample was tested by XRD;most of it is NiFe₂O₄ spinel structure, which mixed with NiO and Cu.2. By optical microscopy, contrasted with the cermets which do not have nano-NiO, the cermetswhich added nano-NiO has lower porosity and metal is evenly distributed, and reticularformation.3.Discoverd that with nano-NiO content increasing, the samples density has augmented.andsintered temperature also affect the density,which has 10% nano-NiO and sintered at 1100℃has better density reach at 95.367% and 5.1672g/cm³,at lower temperature preparation highdensity inert anode, economize energy.4. By using two-port electrodes method the electric conductivities of samples were tested and as a result the best sample's conductivity has reached 103.3133S/cm S/cm at 1000℃, enhanced more than 50S/cm.5. It is discovered that under the electrolyte at 980℃the corrosion resistance, calculated that the corrosion rate is 0.8369cm/a.