You can separate the audio track from video and save it to a DVD disc within Premiere Elements but not a CD disc.
To do save to the audio to DVD disc, you do not have to separate linked audio video, just use the export Publish+Share/Computer/Audio and set Presets to the wanted format (AAC, AIFF, MP3, or Windows Waveform (WAV).
You will not see Audio in the choices since it is at the bottom of the list of choices under Publish+Share/Computer/. You will need to use the thin scroll bar to the right of the choices to scroll to it.
If you need information on selective export of Timeline content when dealing with more than just this one file on the Timeline, please let us know. If you are trying to produce a CD for listening in car or CD player elsewhere, please let us know.
Looking forward to learning of your results.
Thank you for your assistance.
Following your directions, I was able to save the audio to my PC and use Audition CC to burn it CD.
Thanks again for your prompt and helpful assistance.
Great news. Thanks for letting us know the outcome. Great job of follow through to gain your success.