budchemist
Active Member
I thought I would post how I do BHO. My motivation is that I have seen a lot of internet videos/posts that are questionable from a safety perspective. I have 14 years experience as a synthetic chemist including 3 years in natural product extractions. Along with that is multiple degrees in the field. While I dont want to turn this into an academic pissing contest I think it is important that when looking at advice posted on the internet that you should question where the information is coming from.
Note: You do this at your own risk. BHO is hazardous to make.
Always work with butane outdoors. To reduce the risk of pools of butane being created I use a fan to disperse the solvent. Do not use anything that has a motor/heating element anywhere near the setup. The fan is ok because it is pushing the butane away from the motor.
I load my extraction column first with a small amount of whole buds (1 inch layer). This helps stop finer particles getting through. I then load the rest of the column with finally ground flower. I use flower that is air dried first and then silica gel tried to remove every drop of water.
I use round bottom flasks to collect the butane. The reason for this is that I can connect the flask directly to the vacuum when the time comes to dry. Flasks are better than vacuum chambers as you can get away with a lower cost pump. The chambers are far more prone to leakage.
I live in cold climate with an ambient temperature of -5C. If you are in warmer climates I would recommend wrapping the column in a cold pack.
Extraction
1. Open top and bottom tap and push the butane through until you see liquid butane come through the bottom. 2. Close the top tap and then the bottom tap (order important)
3. Let stand 5 minutes
4. Open bottom tap and allow the butane to come out the bottom. Once the butane stops coming through you can safely open the top tap.
5. Repeat step 1-4 until the flask is full (~225mL)
Evaporation
1. Connect aquarium air pump. Always place the pump behind the flow of the fan
2. Use the air pump to blow the butane off (no heat)
3. Once the butane level is at 50% of flask (125mL) you can add cold water into the plastic container that the round bottom flask sits.
4. Once the level is 20% of flask you can add progressively warmer water to drive off the rest of the butane.
5. When nearly all of the butane is remove you can connect a gas adapter and suck off the remaining butane
6. If you are going to use the product without dewaxing you should leave the flask on the pump for 3 hours
Dewaxing (if you are making vape oil)
1. Dissolve extract in 150mL ethanol and warm flask in water bath until the extract is dissolved.
2. Seal flask with rubber stopper and put in freezer overnight. At the same time put a bottle of clean ethanol in the freezer.
3. Prepare a glass funnel by adding diatomaceous earth. Place a filter paper on top
4. Remove extract from freezer. You will notice a precipitate in the flask. This is the wax you want to remove.
5. Filter under vacuum. Wash the filter cake with cold ethanol (5-10mL) (the bottle you put in freezer).
6. Blow off the ethanol at room temperature with the aquarium air pump
7. As the level drops you can warm up by adding hot water to plastic container.
8. Once most of the ethanol has evaporated you can use the vacuum pump to remove the rest.
Note the ethanol can be a little tough on the pumps. I regularly change the oil to prolong the life of the pump.
I am hoping this is pretty clear. Please let me know if there are other photos you want included or you have any questions.
Note: You do this at your own risk. BHO is hazardous to make.
Always work with butane outdoors. To reduce the risk of pools of butane being created I use a fan to disperse the solvent. Do not use anything that has a motor/heating element anywhere near the setup. The fan is ok because it is pushing the butane away from the motor.
I load my extraction column first with a small amount of whole buds (1 inch layer). This helps stop finer particles getting through. I then load the rest of the column with finally ground flower. I use flower that is air dried first and then silica gel tried to remove every drop of water.
I use round bottom flasks to collect the butane. The reason for this is that I can connect the flask directly to the vacuum when the time comes to dry. Flasks are better than vacuum chambers as you can get away with a lower cost pump. The chambers are far more prone to leakage.
I live in cold climate with an ambient temperature of -5C. If you are in warmer climates I would recommend wrapping the column in a cold pack.
Extraction
1. Open top and bottom tap and push the butane through until you see liquid butane come through the bottom. 2. Close the top tap and then the bottom tap (order important)
3. Let stand 5 minutes
4. Open bottom tap and allow the butane to come out the bottom. Once the butane stops coming through you can safely open the top tap.
5. Repeat step 1-4 until the flask is full (~225mL)
Evaporation
1. Connect aquarium air pump. Always place the pump behind the flow of the fan
2. Use the air pump to blow the butane off (no heat)
3. Once the butane level is at 50% of flask (125mL) you can add cold water into the plastic container that the round bottom flask sits.
4. Once the level is 20% of flask you can add progressively warmer water to drive off the rest of the butane.
5. When nearly all of the butane is remove you can connect a gas adapter and suck off the remaining butane
6. If you are going to use the product without dewaxing you should leave the flask on the pump for 3 hours
Dewaxing (if you are making vape oil)
1. Dissolve extract in 150mL ethanol and warm flask in water bath until the extract is dissolved.
2. Seal flask with rubber stopper and put in freezer overnight. At the same time put a bottle of clean ethanol in the freezer.
3. Prepare a glass funnel by adding diatomaceous earth. Place a filter paper on top
4. Remove extract from freezer. You will notice a precipitate in the flask. This is the wax you want to remove.
5. Filter under vacuum. Wash the filter cake with cold ethanol (5-10mL) (the bottle you put in freezer).
6. Blow off the ethanol at room temperature with the aquarium air pump
7. As the level drops you can warm up by adding hot water to plastic container.
8. Once most of the ethanol has evaporated you can use the vacuum pump to remove the rest.
Note the ethanol can be a little tough on the pumps. I regularly change the oil to prolong the life of the pump.
I am hoping this is pretty clear. Please let me know if there are other photos you want included or you have any questions.
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