Many plants produce resin and oil that can be isolated for food flavoring, healthcare, and more. The vast chemical differences in these compounds require distinct extraction methods to isolate them.
There are two main extraction methods: solventless and solvent botanical extractions. Solventless extraction uses nothing but water, heat, or pressure to separate the desired plant compounds. Solvent extraction is more widely used than solventless because it can be done on a larger scale. One of the most popular botanical extraction methods is hydrocarbon. This process uses two main extraction solvents, or substances that dissolve the viscous plant oils into an easily moveable homogeneous mixture. They are butane and propane. Although they’re both room-temperature gases, they can be used in liquid form because of the pressures during extraction.
What are Butane and Propane?
Butane (C4H10) is an alkane natural gas. If you’re wondering what the difference is between butane vs. isobutane, it’s that isobutane is a branched form or isomer of butane. However, the most commonly known derivative of butane tends to be n-butane. This is a highly-refined, flammable hydrocarbon used in torches, cigarette lighters, and stoves. Butane is a non-polar compound.
Propane is a common non-toxic solvent. It’s primarily used in the flavoring and fragrance industries, even though it’s odorless and colorless. The U.S. propane supply is growing in abundance because of the burgeoning market for natural gas. Propane is also a non-polar compound.
Blending the two gasses is a popular practice. That’s because a blend of both solvents yields a greater number of extracted compounds than the solvents could manage individually.
Butane Extraction vs. Propane Extraction
Butane extraction occurs in a closed-loop extraction system. This pushes and pulls the pressurized solvent through a butane extraction tube to recover the gas to its original vessel. Since butane has a boiling point of 30.2℉, it easily re-condenses without the use of extreme temperatures. This makes butane the solvent of choice for passive recovery. Butane tends to yield a more stable extract, as the polar terpenes are left behind.
Propane extraction is like butane extraction but with a higher pressure load since propane has a boiling point of -43.6℉. The subzero temperature helps stop the extraction of lipids and waxes for a more pure extract. These pressures, however, make passive recovery almost impossible without the use of dry ice or liquefied gasses. A recovery pump is used to assist the propane in recovery. Is propane polar? It’s non-popular, and therefore, superior in extracting many aromatic terpenes.
Many extractor operators prefer to use a blended gas of butane and propane. Since they make an azeotropic mixture, the boiling point of the mixed gas ends up being a middle ground between the two parts of the mixture. This allows the operator to have slightly higher pressure than pure butane, without having to operate above 100 PSI. Common mixtures are 70% Butane to 30% Propane (70-30) as well as a 50-50 blend.
Blended gas has different pressure levels at different temperatures. Pressure also increases with higher levels of propane.
The Benefits of Butane/Propane Extraction
In general, whether you go with butane vs. propane extraction, hydrocarbon extraction is extremely useful for large-scale production. Not only can huge amounts of plant material be extracted at once, but the low boiling points of these solvents mean that they can be distilled quickly and without high temperatures. This keeps your product from degrading. Use it for full-plant extracts and to create a variety of consistencies.
With U.S. natural gas quantities dramatically increasing, domestic butane and propane have become preferred choices. But a superior end product must begin with superior materials. BVV butane/propane tanks are made in America and 100% tested before point-of-sale. The high quality and labor standards that go into each product ensure long-term usability and profitability for our customers.
Our butane/propane solutions provide extraction excellence: you get little to no unknown oils and at a cost that makes sense for your operations. Contact us to help you choose the best system for your needs.