We should be clear and distinguish deodorants in general from antiperspirants specifically. Aluminum compounds are the only known effective antiperspirants, you can ask for an aluminum-free antiperspirant but you'll get a product that doesn't work very well (if at all). However, there are many options for aluminum-free deodorants that aren't antiperspirants.

I thought it was well known that antiperspirants should be avoided because of the aluminum.