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Since oxygen is more electronegative than chlorine, if I introduce $\ce{O2}$ gas to $\ce{AlCl3}$ and apply some heat, will the chlorine be replaced by oxygen, resulting in $\ce{Al2O3}$ or $\ce{Al(ClO2)3}$, then evolving the remaining $\ce{Cl2}$ into the air? I suspect not, but why?

Is there a standard way of converting $\ce{AlCl3}$ to $\ce{Al2O3}$?

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    $\begingroup$ You probably can, but it would make little sense; industrially, it's the other way around as aluminium(III) oxide is easily available in large quantities. You can hydrolyze $\ce{AlCl3}$ to $\ce{Al(OH)3}$ and calcine it above 600 °C to eliminate water and what's left would be quite pure $\ce{Al2O3}.$ $\endgroup$ – andselisk Sep 11 at 17:50
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    $\begingroup$ Thanks @andselisk. Though it makes little sense in the current world we live in, my motivation behind this question was imagining a how to create a chlorite in a world without electricity (no electrolysis) $\endgroup$ – R Dev Sep 11 at 18:02
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Yes, you can make aluminium oxide from aluminium chloride pretty much in your way but then again as @andselisk said, it is a pretty inefficient reaction and wastes a lot of fuel and energy and also produces many byproducts. Hence, the reaction is the other way round if considered on an industrial scale. The main preparation method is already described by @andselisk in the comment section. Only to verify its authenticity, here is a patent claim:

A process for preparing alumina which comprises heating aluminum chloride hexahydrate at a temperature of from about 225 to 600 F. For a period of time such as to liberate only a portion of its chlorine content, commingling a basic reagent with the resultant chlorine-containing residue to form aluminum hydroxide, washing and filtering the latter and then calcining to produce the oxide.

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