Cannabis Extracts & Solvents
Since the legalization of cannabis in California in 1996, many states have followed suit. Today 18 states and Washington D.C. have legalized recreational marijuana. Cannabis is legal for medical purposes in 37 states (business insider). The shifting legal status of Cannabis has led to various new ways to consume cannabis other than the traditional smoking of flower.
Manufactured products such as edibles and vaporizers incorporate extracts derived from Cannabis or Hemp. These extracts can be derived with various extraction methods and solvents. We will be breaking down the different solvents typically used in Cannabis and Hemp extraction and what products are generally made through each different process. Extraction technology is ever-advancing. While some processors have proprietary products, processes, and techniques, these are the solvents that are generally used and the products that are produced from them.
- Water/Ice Extraction – Water-based extraction is becoming more popular as new Cannabis users enter the medical and recreational market. The process utilizes the mildest extraction solvent (h2o), which is widely accepted by end users as a safe and effective consumable extract.
This process utilizes a combination of water, ice, or dry ice (which is actually a form of C02) and is typically referred to as Ice Water Hash or Bubble Hash. This type of Cannabis extract is leading the way as hash connoisseurs and producers progress the manufacturing methods utilizing water as a solvent. Live Rosin, Cold Cure, and Ice Wax are high-grade hashes you might see produced with water. Some of these higher-grade solvents utilize a heating step in the form of a heat press after they are processed with water, ice, or dry ice.
- Ethanol or C₂H₆O – Ethanol (the same as the grain alcohol or drinking alcohol that is typically found in spirits) is widely used in Cannabis and Hemp extraction labs. Cannabinoids and other compounds found in the plant are widely soluble in ethanol. ethanol is a GRAS (generally recognized as safe) Solvent for manufacturing and extracting Cannabis or Hemp. It is generally derived from corn or sugar beets and refined at manufacturing plants within the United States. Ethanol is separated from the Cannabis extract via distillation or other fractionation methods of separation such as membrane filtration. This process is often followed by a final step of high vacuum distillation, removing 100% of the ethanol from the cannabis extract. Cannabis and Hemp processors must ensure they are finishing products correctly. The final steps of Ethanol extraction remove ethanol from the Cannabis extract leaving no detectable traces left behind. With zero residual solvents left in the extract, ethanol extracts are a safe and effective Cannabis extract for consumers.
Ethanol extracted products are typically referred to as Whole Plant Crude Extract or Full Spectrum Extracts. Crude Cannabis and Hemp extracts derived from ethanol are composed of more than just the Cannabinoids themselves (such as THC-a, Delta 9-THC, CBD-a, CBD, CBG, CBN, CBC, CBL). Extracting with ethanol also extracts additional materials from the plant such as chlorophyll, fatty acids, esters and a variety of other derivatives. This is what gives the concentrate its name: Crude or Whole Plant Extract.
Crude Cannabis or Hemp ethanol extracts are often refined further through Winterization to remove the unwanted materials, producing Winterized Crude Oil. Winterized Crude Oil is then further refined through high vacuum molecular Distillation, producing THC or CBD-rich Distillate. Cannabis Distillate is a product that is light golden in color and highly viscous in nature and looks and acts like honey. If processed correctly, it should have little to no odor and contain 80%+ Cannabinoids. By the time the ethanol extract goes through the distillation process, no ethanol is left in the cannabis extract thanks to fractional distillation, making it highly safe for human consumption.
Different cannabinoid distillates may vary in color ranging from golden to what is referred to as “water clear” most often when you see the water clear, it will be a form of Delta 8 or Delta 9 THC distillate.
- N-Butane, Propane, or ISObutane – These hydrocarbon extraction solvents have been widely popular and utilized for many years in Cannabis and other botanical extractions. You will often hear these products referred to as LPG’s or Liquified Petroleum Gas. These alkane solvents are gaseous at atmospheric pressure, but become liquid while being stored in a pressurized holding tank. These gases have inherent processing dangers as they are extremely flammable due to their gaseous nature at atmospheric pressure. These solvents are generally recognized as safe (GRAS) in terms of making products for human consumption. The low boiling points make it easy for Cannabis and Hemp extractors to remove the majority of the solvent from the Cannabis extract through distillation that occurs inside the hydrocarbon extraction equipment. The remaining solvent is typically removed inside a vacuum oven, where the extract becomes a finished product. This extraction method is typically used more in Cannabis than it is in the Hemp industry due to its efficiency and quality for producing smokable Cannabis extracts.
Butane or propane hash (BHO) has many different names based on the processing and finishing techniques utilized by the extraction lab. Shatter, Crumble, Honeycomb, Diamonds, Sauce, Live Resin to name a few. Extractors have been getting creative and making different consistencies utilizing LPG’s. LPG hash is also often referred to as Whole Plant Extract or Full Spectrum Extract due to their nature to extract terpenes, cannabinoids and other plant compounds that make for a highly potent, flavorful, and widely desired Cannabis extract.
- Other Hydrocarbons (alkanes) Heptane, Hexane, Pentane – These solvents are used less frequently in the Cannabis industry for extraction of raw plant material. Labs more often use these solvents for other techniques such as crystallization. However, these Alkanes can be used for extraction and are used in many other large scale edible oil productions such as soybean oil. As long as the manufacturing plants and laboratories use the correct processing methods and have proper QC/QA procedures to follow, these solvents can be removed in their entirety or to acceptably safe levels to be safe for human consumption.
- Co2 – Carbon Dioxide has been widely used for extraction throughout Cannabis and various other botanical industries. It is generally seen as a healthier option by the general public but in reality, it is no different than any of the other solvents listed above (so long as the appropriate manufacturing methods are followed). Most often Co2 is manipulated under very high pressures to extract different compounds from the Cannabis plant. The process essentially fractionates these different compounds whether it be the Cannabinoids and Terpenes or creating a Full Spectrum Extract that is comparable to other Crude Full Spectrum extracts.
If you would like to learn more about the different types of extraction, click this link to visit our blogs on the different processes, procedures and types of equipment that are used to produce extracts.