The Biodegradable Extraction Solvent Hisol Plus, 5-Gal, contains 100% natural orange and citrus terpenes. it is nontoxic, biodegradable, ozone-friendly, and rinse freely with no clumping. The Biodegradable Extraction Solvent Excel Clean cannot be used for reflux or other heated extraction methods, but is ideal for use in vacuum extractors or centrifuges for gradations only. Flash point is 145°F for Hisol Plus.