Format a Stuck External Hard Drive

I have an external drive that is basically unusable. It’s just for backups, and I have redundant backups, so I don’t care about losing the data, I just want to completely format it and get it working again. (I highly doubt it is a physical issue with the drive)

This is basically the state the drive is in now:

• The drive has two partitions
• One partition will mount, but cannot be unmounted, even forcing through Terminal
• The other partition will never mount
• Whenever the drive is connected, Disk Utility will stop working

I managed to get the drive to respond and unmount by killing the process fsck_hfs