Final Technical Report Microwave Assisted Electrolyte Cell for Primary Aluminum Production

Xiaodi Huang ; J.Y. Hwang

关键词: CORROSION RESISTANCE;    ELECTROLYTES;    ELECTROLYTIC CELLS;    HEAT RESISTING ALLOYS;    NICKEL;    PRODUCTION;    ALUMINIUM;    CARBON DIOXIDE inert anode;    wetted cathode;    energy intensity;    CO2 emissions;    reducing alumi;   

DOI  :  10.2172/902390
RP-ID  :  DOE/ID/14402-F
PID  :  OSTI ID: 902390
Others  :  Other: #020122, E21722
Others  :  TRN: US200722%%322

学科分类：能源（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

This research addresses the high priority research need for developing inert anode and wetted cathode technology, as defined in the Aluminum Industry Technology Roadmap and Inert Anode Roadmap, with the performance targets: a) significantly reducing the energy intensity of aluminum production, b) ultimately eliminating anode-related CO2 emissions, and c) reducing aluminum production costs. This research intended to develop a new electrometallurgical extraction technology by introducing microwave irradiation into the current electrolytic cells for primary aluminum production. This technology aimed at accelerating the alumina electrolysis reduction rate and lowering the aluminum production temperature, coupled with the uses of nickel based superalloy inert anode, nickel based superalloy wetted cathode, and modified salt electrolyte. Michigan Technological University, collaborating with Cober Electronic and Century Aluminum, conducted bench-scale research for evaluation of this technology. This research included three sub-topics: a) fluoride microwave absorption; b) microwave assisted electrolytic cell design and fabrication; and c) aluminum electrowinning tests using the microwave assisted electrolytic cell. This research concludes that the typically used fluoride compound for aluminum electrowinning is not a good microwave absorbing material at room temperature. However, it becomes an excellent microwave absorbing material above 550°C. The electrowinning tests did not show benefit to introduce microwave irradiation into the electrolytic cell. The experiments revealed that the nickel-based superalloy is not suitable for use as a cathode material; although it wets with molten aluminum, it causes severe reaction with molten aluminum. In the anode experiments, the chosen superalloy did not meet corrosion resistance requirements. A nicked based alloy without iron content could be further investigated.