Evaporators and Their Use with Acids and Essential Oils in the treatment of honey bees
Thymol crystals can be evaporated from the solid (sublimed). Various types of Thymol frame are detailed under the link… Special Frames.
Acetic acid at high strengths is used to fumigate combs that are not in use. It has been used at the strength of a condiment in a "vinegar fogger", but as yet I have no information or experience of this method of use.
Oxalic acid delivered by evaporation as well as direct dribbling, is becoming popular in Europe as an anti varroa method.