Andy Dingley wrote...
I have tried various things to get rid of the odor from propane tanks
that I've reused.

I use a lot of propane tanks, frequently for stoves. Heat is the only
thing I've found to shift the ferret smell. Wirebrushing the inside
isn't a bad start though, assuming you've cut access.

Sandblasting worked ok for me. Of course, this means at least one end has
to be opened pretty wide, but for my application, I needed big holes in
both ends, anyway. Once all the rust was gone and pretty much nothing but
bare metal showed inside, the smell was nearly gone. I wasn't able to
perfectly clean the joint between the two halves, and I think that's
where a little bit of odor lingered. After sitting a few days, the smell
was gone completely, though.

Jim