Question by Jack in the Box: Why don’t they use waste aluminum to generate hydrogen for fuel cells?
I find aluminum over NaOH is the easiest way to produce hydrogen (600 g Al can yield 70g=1litre liquid h2)

Best answer:

Answer by slew
What in the heck is Waste Aluminum??? Most Aluminum is recylcable, and it requires ALOT of energy to produce it.

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