This question already has an answer here:

Is there a way to create color separated PDFs through QGIS's print composer?

I've also tried different PDF printers, but I haven't find any free option for it.

marked as duplicate by Steven Kay, whyzar, Mapperz Sep 7 '17 at 19:11

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • What do you mean by color separated pdfs? Could you edit your question to include some example images? – csk Aug 2 '17 at 15:15
  • i think this might be a duplicate of this question. I believe this is still the case, as of QGIS 2.18x / Qt 4 (the limitation is in Qt). If you want CMYK separations you might need to use Inkscape, GIMP, Scribus or similar to produce those using PDF/SVG or Image outputs from Composer. – Steven Kay Sep 7 '17 at 17:39
  • 1
    Seems you could try doing it afterwards : helpx.adobe.com/acrobat/using/… or with Foxit : smallbusiness.chron.com/change-pdf-cmyk-printers-57070.html – gisnside Sep 7 '17 at 18:04