Are there any mobs that don't drop loot?

I am trying to find a good spot to get a lot of emeralds from looting, but everywhere I try, the mobs drop a bunch of loot that clogs my inventory and prevents me from picking up emeralds. preferably this would be a mid to low level area.

 

Just put a single emerald in your inventory and any picked up ones will go into the pouch, even when your inv is full since it still gets added to the stack in your inv

 

Thanks, this worked really well