I need to find a proper method to prepare sample solution by digestion for Pt-Pd-Rh elements from spent automotive catalysts. Any suggestion except application of microwave-assisted digestion would help me.
Don't know about your sample but I'd suggest alkaline fusion followed by dissolution in nitric acid. You'll however have to find the right flux and very probably check if you need to pre-oxidize your metals first. You'll also probably want to avoid Pt-Au crucibles in your case.
I suggest you contact your local representative of Claisse-Panalytical or Katanax to discuss this with them (fluxers suppliers).
Check this :https://www.azom.com/article.aspx?ArticleID=11593