Part of the point is to reduce the ketone and imine once it's produced. Okay, so you have Al2O3, this means that a rather vigorous reaction is going to occur, as Al2O3 converted to 2Al(OH)3 and that's one of the driving forces of the reaction as I understand it. Probably too fast. Just a thought, but how would you control that reflux? I guess A WHOLE LOT LESS Hg salt. What's wrong with Al foil?
BTW, I may be completely full of shit, but Post 269032 (https://www.thevespiary.org/talk/index.php?topic=7427.msg26903200#msg26903200)
(Osmium: "Re: Hg Amalgamation rates", Chemistry Discourse) is a great explanation of the reaction creating the reduction.
Who wants to play cops and dope fiends?
When you reduce something, something else is oxidized.
Hence the term "redox."
PB
Put your left leg down - your right leg up,
Tilt your head back - let's finish the cup!