What is CO2 oil, and how is it different from other cannabis concentrates?
What has become known in the cannabis industry as “CO2 oil” is a type of marijuana extract that’s made by using carbon dioxide as a solvent. The process is called “supercritical fluid extraction” (SFE), and it’s widely used in a variety of industries, including dry cleaning, agriculture, food, and herbal supplements. Supercritical CO2 is a common method of decaffeinating coffee, for example, as well as extracting metals and pesticides from crops. Although the technology has been used for decades, the relatively recent legalization of cannabis products in the U.S. has sparked great interest in using it to produce pure, potent, and clean marijuana concentrates.
Solventless vs. Solvent Extractions
There are two basic ways of creating cannabis concentrates: with solvents and without. The simplest concentrates, kief and ice-water (or “bubble”) hash are made by physically separating the trichomes from the plant material. Other forms of concentrate are made using various solvents to extract the essential components.
How SFE Works
CO2 extraction requires more sophisticated (and expensive) equipment to produce than other forms of extracts. Cannabis plants are placed in a chamber that is then filled with pressurized carbon dioxide. The pressure and temperature inside the chamber are increased until the CO2 reaches the “supercritical” state, a form in which it behaves like both a liquid and a gas. In this form, the CO2 diffuses through the plant material, penetrating the cuticles of the trichomes and dissolving essential oils.
CO2 vs. Other Solvents
Common solvents used to make cannabis extractions include butane, hexane, propane, ethanol, isopropyl alcohol, and, of course, CO2. Supercritical CO2 has become the preferred method for many extractors, patients, and adult users due to its safety and the purity of product it can produce.
Because CO2 is naturally occurring and nontoxic, many consumers feel safer consuming oil produced in this way over concentrates that have been made with solvents such as butane, hexane, or propane. Alcohol solvents dissolve undesirable plant material, such as chlorophyll, along with essential oils, creating a less appealing flavor.
The SFE process destroys natural contaminants such as mold, mildew, and bacteria. However, as with any solvent-based extraction process, any pesticides or other residual chemical additives contained in the initial plant material would remain in concentrated form. Ask your budtenders for details about the CO2 oil products they carry, including any lab test results that are available and any knowledge they have about growing practices (organic, pesticide free?), so you can make the most informed choice possible.
Nature’s Gift Shop, a retail marijuana dispensary in Pueblo West, carries a wide selection of lab-tested cannabis concentrates, including CO2 oil. Stop by and check out our selection! Before you do, download the coupon below to get 4 grams of your favorite bud for the price of an eighth!
 Dorm, "Supercritical Carbon Dioxide (CO2) Extraction: Pure Cannabis Oil." Medical Jane. n.p., 11 April 2014. Web. 13 Nov 2015.
 Soriano. "Dabs 2.0: CO2 Extraction for Cannabis Concentrates." High Times. High Times, 25 March 2014. Web. 13 Nov 2015.