Conversion of CBD to THC with citric acid and water-based extraction - PsychonautWiki

Conversion of CBD to THC with citric acid and water-based extraction

Alternative conversions

The below recipie may be used to convert the following phytocannabinnoids (without residual metals found in related commercial CBD converted products like vape cartridges, gummies, etc):

  • Cannabidiphorol (CBDP) to tetrahydrocannabiphorol (THCP) which is 30 times more potent than THC.
    • CBDP is produced by decarboxylating CBDP acid (CBDPA).
  • Cannabidihexol (CBDH) to tetrahydrocannabihexol (THCH) which is 25 times more potent than THC.
    • CBDH is produced by decarboxylating CBDH acid (CBDHA).

The above substances are currently not scheduled by any United Nations treaty unlike THC or THC acid (THCA). However, in the US they could be considered an analog of THC, in which case, sales or possession intended for human consumption could be prosecuted under the Federal Analog Act.



Conversion of CBD to THC with citric acid and water-based extraction Before we start - my intention with this guide is to show people that possessing basic cooking skills and equipment qualifies you to turn CBD into THC! For too long, the person who just wants to chill out and get stoned has been forced to exchange excessive money for THC, but no more! CBD is generally available for sub-$1/gram and can by converted to THC like 90% efficiently using relatively common cooking ingredients, techniques, and equipment (and some lab ware!) Thanks to inspiration from this sub to get me started and my brothers in science who have inspired me to apply my knowledge to the age old problem of “how do I get stoned with less labor?”. This technique strives to be as simple and as approachable as possible. I'm not a chemist, I'm just a tinkerer who hates overpaying in general and especially for THC. I think this technique is about as simple as can be, it was important to engineer a process I couldn't screw up and could perform with minimal equipment. To keep this safe, we only use food-grade ingredients and you should only eat the product, you should be able to eat any ingredient at any step of the reaction and get irritation at worst. If you perform this technique, you'll have incredibly pure THC that doesn't cost much more per gram than your source of CBD.

Ingredients and ratios: 

  • CBD isolate (isolate preferred, distillate acceptable also, higher purity is better).  “hemp depot” has good prices, you can get CBD for less than $1/gram if you look hard enough
    • as-of May 2022, you shouldn't pay much more than $600/kg for CBD isolate
  • Food grade citric acid (start with something on the order of 100-500 grams)
  • Baking Soda (get a container at the grocery store)
  • Pure water (use distilled water if you’re unsure of what this means or how to measure water quality, you’re looking for water with fewer than 50 PPM of total dissolved solids) 
    • You’ll want ice cubes, a few ice cubes should be enough but make sure they’re made of pure water
    • You'll need to boil some of this eventually, make sure you can heat and handle the boiling water without contaminating it. A clean GLASS cup should be enough

Equipment (this will change as your batch size changes, I normally cook ~10 grams at once this is the equipment setup that I think is most rational, adapt these to your use case): 

  • Scale with .01 gram precision (at least 100 grams of max capacity)  - $20
  • Labasics 200 mm graham condenser with 24/40 joint - $20
    • The water jacket should accept ½ inch tubing  
  • 24/40 glass stopper - $10 optional
  • A small submersible water pump (like 5 watts)
    • make sure you get enough lifting height, if you're not sure try to get at least 1 meter of lift height) for your setup
    • get a half-inch nozzle if you follow the condenser recommendation (you’ll want to match your water pump nozzle size to your condenser’s water nozzle size) - $5
  • ½ in plastic tubing  - $10
  • Container to hold water and your pump (shoot for at least 2 gallons) - note that this won’t be exposed to chemicals, you can use a mixing bowl or VERY LARGE tupperware 
  • 24/40 boiling flask (I got 250 ML, you’ll want to use less than half the capacity - 125 ml is enough space to convert ~70 grams or so) 
    • Your choice on whether to get a round bottom or flat bottom
  • A stand to hold your equipment (consider United Scientific SSB6X9) 
  • Clamps to hold the equipment (consider EISCO CH0688)
    • You need at least one, but ideally two: one for the boiling flask and one for the condenser 
  • Heating plate- 
    • You’ll want something with magnetic stir capabilities, the most basic hot plates with the stirring are $60-$80, you’ll need to figure out how to measure the temperature of the solution inside the flask if you do this though
    • Heating plates with thermal control capabilities start art $200, buy once cry once - you’re going to make THC for sub-$1/gram - you probably pay $20-$40/gram for it now, just invest in the good equipment now and recoup the savings in the future
  • Magnetic stir bars (if not included in with your hot plate or you want more sizes) 
  • Stainless steel strainer
  • Bowl (you can use a clean kitchen bowl that’s glass or non-stick, just wash it well before using it for food) 
  • Glass or silicone containers for the final product 
  • silicone spatulas for handling
  • Coffee filters (optional)
  • IR thermometer - $15, just useful to have to check temperatures

Procedure Vision for the process: When CBD is exposed to acidic solutions, the CBD molecules undergoe isomerization which means they are reconfigured into THC. There are multiple types of THC, the process first converts CBD to THC-delta-9 (the type most commonly found in plants, most people prefer this type) and ultimately to THC-delta-8 (a less psychoactive variety of THC). After isomerizing the CBD into THC, we will neutralize the acid which converts the citric acid into sodium citrate and use water to separate the THC from the sodium citrate.  Steps: 

  • Set up your equipment 
    • Find a spot for the heating plate, put your flask on top of the plate, and ‘test fit’ everything without loading any material in the beaker
    • Put your condenser on top of the beaker, use plastic tubing to attach the water pump to the water jacket of the condenser
      • Pro tip: attach your pump to the lower water nozzle on the condenser, this will ensure your pump fills the condenser and the condenser works as effectively as possible 
  • Prepare the reaction
    • It’s very important to get the right mixture of ingredients here
      • Even ~7% less citric acid than required will reduce your reaction efficiency dramatically
      • Using too much citric acid will make extra sodium citrate which means for filtration later
      • You need to use Water and Citric acid in a 1 gram water to .15 gram citric acid ratio regardless of how much water you use 
      • You should use at least 2 grams of water (and .3 grams of citric acid) per gram of CBD you want to isomerize 
      • You can use more water per gram of CBD but make sure you use .15 grams of citric acid for every gram of water, you should only do this if you’re reacting fewer than ~3 grams of CBD or so, after 5 grams, there should be enough water normally that this is reasonably easy to handle 
    • Select however much CBD you want to convert (this process should be around 90% efficient at converting CBD to THC)
      • For each gram of CBD, measure out two grams of water and .3 grams of citric acid (15% solution)
      • For 10 grams of CBD, use 20 grams of water and 3 grams of citric acid 
    • Put the measured amounts of CBD, water, and citric acid in the flask, the order doesn’t matter
    • Put the flask between the condenser and the hotplate, heat the solution inside the flask to boiling and run the magnetic stirrer between 200 and 1000 RPM (or, as high as possible without the magnet flying out of control or splashing your solution) 
      • My hotplate has a temperature controlled heating pad, I set the pad to ~130 degrees C and put the flask with the solution on top in a round bottom flask with a lot of foil to conduct and insulate heat
  • Run the reaction
    • After your solution is boiling and getting mixxed, run it for ~8 hours while under reflux (boiling under the condenser) where it’ll have a ~50/50% ration of delta-9 and delta-8 THC. Running the reaction longer will convert the delta-9 THC to delta-8, after 12 hours or so, it should be entirely converted to delta-8.
  • Neutralize the Acid
    • Tip: At this point, I normally stop the heat and pull off the condenser apparatus and drain it/set it aside, and keep the stirring going while pouring in the baking soda
    • Pour in 1.31 grams of baking soda for each gram of citric acid
      • if you’re following along for 10 grams of CBD, that’s 3.93 grams of baking soda
    • I normally don’t pour in all the baking soda at once, I start by dumping in ~90% of the baking soda and adding the rest slowly, if you pour in baking soda and there’s no fizzing, it may mean the acid is fully naturalized
    • Check the PH if you can, add baking soda to fully neutralize solution
  • Get ready to separate the THC and water / sodium citrate
    • Put your ice cubes in a stainless steel mesh strainer
    • put strainer over a bowl to catch water
    • pour the contents of your beaker out over the ice slowly - the goal here is to pass as much water as possible over the ice so that the THC will crystalize
    • 70-80% of your THC will congeal together (this will be bound up with sodium citrate) in the stainless steel mesh
    • Your choice on how much you want to filter and try to conserve the THC in the water/sodium citrate, it’s best to discard the fluid down the sink or run it over a coffee filter and try to operate out the THC
  • Solventless extract
    • Right now, your THC is bound together with sodium citrate, you need to separate the two. Luckily, sodium citrate is water soluble and THC is not, we’ll use this property to separate out the two
    • Begin Loop until you have something clear (3x to 5x rinses)
      • Pour your hot THC (read: liquid) THC into a stainless steel mesh with ice cubes, pouring directly on top of the ice cubes
      • With your THC in the stainless steel container, remove the Ice cubes
      • you can rinse the solution over the sink with cold water if you want, briefly, this helps a little, discard the rinse
      • prepare to catch hot THC and water under the stainless steel mesh
      • pour boiling, pure water over the THC and stainless steel mesh - the boiling water liquifies the THC allowing sodium citrate to dissolve in the water
      • If your THC / water solution gets cold, you can put it in the microwave, just be careful not to let the THC get above 220 degrees or so
      • this was your first rinse, congrats!
      • To repeat, Pour your hot THC (read: liquid) THC into a stainless steel mesh with ice cubes, pouring directly on top of the ice cubes
  • When you’re finished, just take your THC crystals/solution and put it in a container and let the rest of the water evaporate
  • Finished! Now dab it or eat it
    • Technically, you can eat this before this is neutralized, but best to neutralize the acid before eating

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