Although there are many home methods to extract CBD from the hemp plant, there are four basic commercial processes:
CO2 Processing: Considered the most advanced, cleanest and expensive form of processing, as it requires very expensive equipment such as the one pictured above. First the carbon dioxide (CO2) is converted from gas to liquid by decreasing the temperature and increasing the pressure. Then the pressure and temperature are both increased to obtain what’s known as the supercritical stage where the CO2 takes on properties of both liquid and gas. It is then pumped through a canister of plant material wherein it separates and removes all the cannabinoids from the plant material before moving into another chamber where the CO2 simply evaporates. The machine above will process up to 15 pounds at a time and produce 400-700 grams of full spectrum extract.
Solvent Processing: This has the potential of being a very dangerous method of extraction because it involves using flammable substances such as ethanol, butane or propane. The plant material is immersed in the solvent which extracts the cannabinoids. The solvent is then removed using distillation or other methods. The hydrocarbons do a great job of preserving the plants terpenes (essential oil-like aromas), but has the potential of remaining in the extract if removal is not executed properly. Ethanol can also extract chlorophyll which can give the extract a bad taste.
Steam Processing: Or processing by distillation, is not as popular as the above 2 methods as it requires more plant matter and destroys sensitive terpenes in the heating process. It is cheap and solvent free, but the final product can also easily lack consistency. The steam releases the cannabinoids into a vapor which is cooled and then separated from the water.
Oil Processing: Usually with olive oil or butter, this is not a commercial application, but an inexpensive home method that is also solvent free and thus safe to perform. The plant material is mixed with the oil and heated to extract the cannabinoids. The plant material is then filtered out. It is far less efficient than other methods of extraction and the extract becomes permanently infused in whatever oil is being used.