THC remediation is the process of removing THC from a cannabis extract in order for it to be compliant with the law, which deems any cannabis product with more than 0.3 percent THC federally illegal. It’s an indispensable step toward producing the multitude of CBD concentrates we see on the market.
THC remediation can be done in numerous ways: reverse-phase chromatography, high-performance liquid chromatography, centrifugal partition chromatography, counter-current chromatography, supercritical fluid chromatography, crystallization, dilution, and THC degradation.
In short, chromatography and THC degradation are the two most common methods of THC remediation.
Chromatography does a great job at separating nonpolar compounds like THC and CBD, as the two react differently to the silica. Nonpolar compounds like certain cannabinoids can be separated to levels above 90 percent and there is the possibility of using the same technology for terpene purification. So chromatography is great for full-spectrum extracts as well as CBD isolates. Although achieving a 100 percent pure CBD isolate may not be possible, something in the high 90s would be attainable.
THC degradation, meanwhile, relies on the natural aging processes that cannabis undergoes. This usually involves exposing the flower to light and heat and creating a favorable environment to speed up the degradation process. This causes THC to convert into CBN, which has only around 10 percent of THC’s potency. 
This method’s simplicity is its charm and its downfall at the same time. For starters, CBN’s 10 percent psychoactivity in relation to THC’s isn’t the same as zero percent, which is some CBD consumers’ goal.
Moreover, when concentrated, that psychoactivity can basically get concentrated as well and increase due to CBN’s potential concentration in the extract. Finally, THC isn’t the only cannabinoid that’s vulnerable to light, heat, and time, so this method can come at the cost of all-around cannabinoid degradation.
As you can see, making a CBD extract compliant with the federal law is anything but straightforward and comes with several challenges. Hopefully the advancement of the industry makes those challenges more and more easy to overcome. We’re already seeing such advancements in the form of proprietary equipment like T-SEP by Precision Extraction.
Image Credits: pxhere / mohamed hassan
References: Jaidee W, Siridechakorn I, Nessopa S, Wisuitiprot V, Chaiwangrach N, Ingkaninan K, Waranuch N. Kinetics of CBD, Δ9-THC Degradation and Cannabinol Formation in Cannabis Resin at Various Temperature and pH Conditions. Cannabis Cannabinoid Res. 2021 Jun 4. doi: 10.1089/can.2021.0004. Epub ahead of print. PMID: 34096805.