To be clear, he's talking about reusing the wire, but with a 20 amp breaker.
(note to the original poster, you didn't say where you're located so this advice assumes you're in the US - if you're somewhere else it may be different.) You don't need to use a 20 amp duplex receptacle, per the NEC if you have two or more receptacles on a 20 amp circuit they can be the 15 amp type, and a duplex receptacle counts as two.
As for the wire, it can be reused as well if it has black, white and ground (bare or green) conductors. Most standard receptacles will take up to #10 wire, although it may be difficult to bend and install.