It's not a private key it's a brainwallet.

1) Go to https://www.bitaddress.org/
2) click on brainwallet (upper right)
3) Disconnect from internet
4) Verify that you are offline
5) Be 100% sure you are offline
6) Verify steps 4 & 5
7) Click on show so you can see what you are typing.
Put in what is there CApitAlizatiON matters
9) Click on view it should show the address and key.

-Dave