Hi,
Yes, you can use the 10G port just like any port.
I believe there was a 10GBase-T VIM for the x450e, but if you don't have one then that's going to be problematic.
We are starting to find Copper SFP+ on the market, but they do not follow MSA Type II recommendations, especially in regards to power (2.5W or even more instead of 1.5W). I have no idea if it would work on this platform.
The best way would be to find a 10GBase-T VIM for x450e. Of course, you can also consider moving to a X460G2 with a copper 10G VIM.