SQL Server 2012 compatibility with Microsoft Server 2016
Yes, OS (Windows Server) and database (SQL Server) are separate entities. So the only question is compatibility between those two products.
I'm guessing it was tested and should be ok, but at this moment SQL Server 2012 doesn't have Windows Server 2016 listed (and won't have, at least not till September):

https://msdn.microsoft.com/en-us/library/ms143506%28v=sql.110%29.aspx

Best thing You can do is download latest Technical Preview and test it with SQL Server 2012 in Your environment:

https://www.microsoft.com/en-us/evalcenter/evaluate-windows-server-technical-preview