You’re suggesting it makes sense to replace “Carbon based solvents” with terpenes?
That implies you don’t have a clear understanding of what terpenes are. I’m not certain you’ve got fermentation of ethanol under your belt either if you consider it “petroleum based”.
That said, raising your hand with published data showing how well readily available plant derived solvents (α-Pinene, D-Limonene) could substitute for solvents that some of us prefer not to use, and other’s don’t have access to due to regulatory restrictions (hexanes, pentane) is very helpful to the community.
Using terpenes as the primary extraction solvent in cannabis is arguably already a thing. that’s much of the magic behind rosin, and how many CO2 rigs are tuned.
when recovering your primary solvent, the enthalpy of vaporization & the boiling point dictate how much energy you need to apply to vaporize, then condense your solvent. given that the boiling points are higher, and the enthalpies are similar, ethanol will probably require less energy input per unit biomass processed.
If D-Limonene is truly a waste product (unlike α-Pinene?), then you’ve got a win vs distilling Ethanol. Pretty sure the energy inputs for making α-Pinene vs Ethanol lay 2:1 or better in favor of ethanol.
Guess it depends on what you call “green” and why.
I’d like to see hemp operations making their own solvent from their spent biomass. using the spare sunshine they obviously have to power their stills, and their solvent recovery at least some of the time. Cooling water to the plants.
there are of course other things one can do with hemp