when you redeem miles you've already earned on united, you won't get any additional elite qualifying miles (eqms). you only get eqms for the miles you fly on paid (not award) tickets and for a few other promotional things.

when you purchase additional miles, they are only redeemable miles, and you won't get any additional eqms, unfortuantely. (it would be great if they did though)

hope this helps