Well, the Aluminum is recyclable, so the fuel pellets, once exhausted can be turned in to be reused. Additional advantages, people would be more apt to re-cycle their cans and containers because of a higher price in face of higher demands........
True, but if this is going to be a large-scale replacement for petroleum products, there's going to have to be a HUGE initial influx of aluminum into the supply stream, which means intense mining. And our Green "friends" aren't going to like that, even if it means reducing vehicle emissions to nearly nothing, so best to consider how to neutralize them now, before this goes large-scale.
Of course, given the weight issue, I'm sure there will be some applications where weight is a critical factor that will still use some kind of petrochemical, but a combination of hydrogen power and biodiesel would reduce our dependency on petroleum to near nil.