Ive thought about this before, probably not a good idea to do it but for the sake of discussion I’ll provide some inputs.
As @Roguelab mentioned hydrogen chloride in a glass/PTFE chamber might be able to spur some isomerization but your going to have a metric fuckload of side reactions which would make god knows what making it both potentially dangerous and unviable. Plus working with hydrogen chloride is a no go for anyone who has to ask about viability of isomerization to begin with imo. Trust your lungs and skin will thank me, hydrogen chloride is some nasty stuff.
I’m just spitballing here, the following is just an idea and I have not tested it, but for the sake of discussion I’ll throw this into the ring in hopes of some adventurous soul with more time than me can potentially test.
There’s a really cool phenomenon that hasn’t been tapped into yet in cannabis as far as I know; Photoisomerization, is a great technique that maybe has potential here, essentially your using various wavelengths and intensities of light to induce the structural changes within a molecule; the question is will there be enough energy to facilitate the full ring closure to fully isomerize the cbd to d8/d9. Penetration will be a major issue with this as only the outer surface areas will be acted upon by the photons.
I’ve Been going down the photochemistry rabbit hole quite a bit in non cannabis stuff lately, it’s pretty cool and there are tons of potential applications in cannabis for it!
Anyways here’s some food for thought and some rabbit holes to explore.
Also don’t convert biomass😂