Cold Solvent = Cleaner Extract
Here is the basic idea: warm ethanol is not picky about what it dissolves. It will happily pull out the active compounds, terpenes, waxes, chlorophyll, and lipids all at once. Cold ethanol is more selective — it goes after the compounds you actually want and mostly ignores the stuff that makes post-processing harder.
The colder your ethanol when it contacts the biomass, the less cleanup your crude extract needs afterward. That means less time, less expense, and a cleaner end product.
How Cold Do You Actually Need?
| Temperature | What it does | Chiller needed |
|---|---|---|
| Around −20°C (−4°F) | Reduces waxes but chlorophyll still comes through | ELT Series |
| Around −40°C (−40°F) | Standard cryo target — significantly cleaner crude | SLT Series |
| −60°C to −80°C (-76 to −112°F) | Deepest cryo — cleanest possible crude, minimal post-processing | ULT Series |
Hydrocarbon Extraction Is Different
Butane and propane extraction works differently than ethanol. You are subcooling the solvent — keeping it liquid under pressure at very low temperatures. The typical target is around −54°C (−65°F). This usually requires two chillers working together: one to condense the solvent, one to subcool it.
What About Solventless?
Solventless (ice-water) extraction does not require extreme cold. It just needs very cold water — around 35–40°F (1–4°C) for the agitation bath. A standard low-temp chiller handles this easily and costs far less than the ultra-low temperature equipment needed for ethanol or hydrocarbon work.
The Chiller Also Works During Recovery
People often think about the chiller only for pre-cooling the solvent. But during solvent recovery, the chiller is still working hard — condensing the ethanol vapor coming off the evaporator so it can be collected and reused. An undersized chiller slows down recovery, which means longer run times and higher costs.
Size for the whole process, not just the pre-cool. Your chiller needs to handle both stages, often at the same time.
See the full Botanical Extraction page for specific model configurations and real customer setups.
FAQ
How cold do I need to go for ethanol extraction?
Around −20°C works at a basic level, −40°C is the common sweet spot, and -60 to −80°C gives the cleanest crude with the least post-processing.
Is ULT the same as cryogenic?
No — ultra-low temperature (to about −80°C) uses cascade refrigeration. Cryogenic means liquid-nitrogen territory, which is a different approach.
Still Not Sure What You Need?
Tell us what you are cooling and we will figure out the right chiller for you. No jargon, no catalog. Just a straight answer.