Partially Full C02 Canisters (Abbeyhill EH7)

I have 2 partially full C02 canisters for a fizzy water maker, can't recycle them at a centre because they're not fully empty but didn't know if anyone could get any use out of them/use them in some way! Brand is C02You and 1 is mostly empty, the other partially full but as my machine is broken there is no way to tell how full exactly.