Sorry, I did not read your post carefully and gave you what would need to be done with a Mac.
I have never paired a Bluetooth device with my iPad, so I am fishing.
This article will tell you how to unpair the KB (click on "how to stop using...")
Thanks the link worked, for anyone else joining this is what you do.
Thanks again Barry
You can stop using a Bluetooth accessory by either turning off the accessory, or turning off Bluetooth on iPad.
Unpairing a Bluetooth accessory
If you've paired iPad with an accessory that you no longer wish to use, you can unpair the accessory.
From the Home screen choose Settings > Bluetooth2. If Bluetooth isn't on, turn it on.
Choose the accessory and tap Forget this Device.