re: Problem 1 -- Fuel delivery
"So refuelling my car will take 350 lbs of SOLID material? And then removing an even greater weight (the Al will be oxidized) of solid waste product and transporting all that back to the refinery?!?!"
Well, 20 gallons of gasoline weighs about 120 lb.
But could you show how you got 350 lb number and how many gallons gasoline that equals.
350 lb doesn't seem much in comparison to the lead battery weigh needed for electrical cars.
But I agree that gasoline is pretty good in terms of having a lot energy and easy to handle.
"Al has a density of about 3.5 or so"
No, it's 2.7.
Or 2.7 times the density of water.
Though Aluminum oxide could weigh around 3.5.