Brainwallet using private key to get pass phrase

[pcme]

Hi guys remember brain wallets?

I was just wandering if you have the public and private key for an address is it possible to generate somehow the passphrase used to generate the address?

I have 10 old brain wallet addresses from years ago and I am just curious I'm sure it can be done

Your help on the matter will be appreciated

[pcme]

I thought I could use qr code but it doesn't work. Any ideas?