Abstract
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The production of Al from its ores at present relies on the Bayer (alumina production) and the Hall–
Heroult (Al production) process. The cost associated with alumina production and apparent
disadvantages of the Hall–Heroult process have led to intensive research to find alternative routes
for Al production. The direct carbothermal reduction process has been thoroughly investigated as
an alternative technique. Another alternative includes the indirect carbothermal reduction route
where alumina (or aluminous ores) is first reduced to intermediate Al compounds before reduced
further to Al. The present study reviews and provides systematic thermodynamic analyses of
alternative Al production routes. In this paper (Part 1), a comprehensive review of alternative Al
production techniques focusing on the indirect carbothermal reduction routes is presented. These
include carbochlorination, carbonitridation and carbosulphidation routes for the formation of
intermediate Al compounds, followed by various Al extraction processes.