Method for increasing concentration of extracts

I am using reagent grade propylene glycol (99.9% pure) and vegetable glycerin (99.7% pure) separately as solvents to extract certain active essential oils/molecules of various plant flowers.


The question is about after saturating the solvents with the essential oils. Can you further reduce the infused solvent solution volume? I am starting with 50 fluid ounces and want to reduce the solvents to 30 fluid ounces.


The goal is to concentrate the the solvent solution and not harm the active ingredients suspended in the the two solvents. The solvent boiling temperature is known and the essential oils/molecules are destroyed 80 degrees below the solvent's boiling points.


