Activated charcoal has many practical uses in survival, from filtering water to making your own gas mask or treating poisoning.
Making your own takes time, but it is ultimately more cost-effective.
Making activated charcoal involves mixing powdered hardwood charcoal with a chemical such as Calcium Chloride and heating it to a high temperature. (Note: you can also use fibrous plant material such as coconut shells if hardwood is unavailable and lemon juice as a substitute for Calcium Chloride.)
A pound of activated charcoal costs $12-$15 while making your own is less than $1 per pound.
For $20, you can have enough activated charcoal on hand for bartering, trading, or helping others during a survival situation.
How To Make Activated Charcoal
Basic Steps
- Burn hardwood to make charcoal.
- Cool overnight.
- Powder the charcoal using a hammer or mortar and pestle.
- Add calcium chloride solution.
- Spread on a clean sheet or cheesecloth.
- Bake at 250 F for 30 minutes or until all moisture is gone.
These are the simplified steps; keep reading for more in-depth instructions.
Making your Own Charcoal
While you can make your own charcoal to activate, the extreme temperatures it takes to burn hardwood down to charcoal make it very time-consuming and energy-intensive.
Instead, I recommend buying a 20 lb bag of hardwood charcoal and using that.
You may have to make your own charcoal (more below) during a survival situation, but if times are still good enough to buy it, you will come out ahead on the deal.
To make charcoal from burning hardwoods or coconut shells.
- Gather a large pile of hardwood. Ensure you have a good spot to burn for a long time, and you can access it to feed it. A lot of people use a metal barrel.
- Chop hardwood into small pieces. You want to maximize how much you can fit in the barrel.
- Build up a big bonfire that will burn for 3-5 hours around your barrel. The length of time is dependent on how big your barrel is and how full you have it. A 55-gallon metal barrel full of wood needs a 5-hour burn time.
- Let the barrel cool overnight or more before opening.
You can make a lot of charcoal this way, and the bonfire on the outside can be made from old wood lying around your property or even slag from a sawmill if you can get it.
Supplies Needed
1. Calcium chloride, otherwise known as Pickle Crisp.
It is most economical to buy in larger tubs like that offered by Hoosier Hill. (Amazon Link)
You can use the Ball Pickle Crisp available at grocery stores, but it is usually a lot more money. Lemon juice will also work in a pinch.
2. Charcoal
Buy whatever hardwood charcoal briquettes you prefer.
Ensure you don’t accidentally get the type already soaked in lighter fluid or has other additives. You need pure hardwood charcoal.
3. Glass Jar or other non-aluminum mixing pot with a solid lid.
Many people use a regular canning jar.
Mixing the calcium chloride causes a reaction that releases heat, and aluminum is a reactive metal. You don’t want to get this on your hands, so use something you know doesn’t leak. Eye protection is always a good idea, just in case.
4. Water and measuring cup
5. Cheesecloth Or White Sheet
6. Cookie Sheet or Flat Pan
7. Storage Container For Finished Activated Charcoal
Activating the Charcoal
- Make Charcoal.
- Powder the charcoal. You can do this by smashing with a hammer or using a mortar and pestle. Transfer to a glass or stainless steel bowl.
- Make a 25% solution of calcium chloride using your water. One hundred grams of calcium chloride would be dissolved in 300 mL of water. This equals 3.5 ounces of calcium chloride and 1.3 cups of water in ounces.
- Make a paste – slowly add the calcium chloride solution to the powdered charcoal and mix until a spreadable paste has formed. Drain any leftover solution.
- Let dry in the bowl for 24 hours.
- Spread on a clean white sheet or multiple levels of cheesecloth. Don’t use anything with detergents or scents. Rinse with clean water and catch the water that goes through. You can filter this water through a coffee filter to recover the carbon you would otherwise lose. Put the coffee filter on a cookie sheet with the rest of your activated charcoal.
- Bake what you have rinsed at 250 F for 30 minutes or until all moisture is gone.
- Cool and break apart to store in an airtight and waterproof jar. (Read more about how to store activated charcoal properly.)
Here is an excellent video on the process.
The Difference Between Activated and Regular Charcoal
Activated charcoal is hardwood charcoal that has been treated to increase the surface area of the carbon particles by creating tiny pores. This activated charcoal can absorb more toxins, impurities, and gases.
While regular charcoal has some absorbing capabilities, it should never be used in place of activated charcoal since the absorption level is far lower.
For more on this, see our post – Activated Charcoal vs. Charcoal
Survival Uses For Activated Charcoal
1. Emergency water filter
Some filters have sections that require activated charcoal. It can reduce and eliminate chlorine, fluoride, and other compounds and tastes you don’t desire in your water.
We wrote about DIY Charcoal Water filters here, or below is a great video showing how to use activated charcoal to make a high-volume water filter using only a 2-liter soda bottle, activated charcoal, and a coffee filter.
2. Remedy for ingested poisons, including overindulgence in alcohol
Charcoal absorbs toxins, and that means that it can save a life. If a poison is consumed, then eating some activated charcoal can reduce the effects.
Some people use it if they have too much alcohol to drink. This means that if alcohol poisoning is suspected, charcoal can help reduce blood alcohol levels.
To Treat Poisoning
It is important to remember to give activated charcoal as soon as possible. The best time is within 30 minutes of a poison being consumed. Activated charcoal should never be given to children under 1 year of age.
Recommended Reading: Disaster Prepping with Children: From Infancy to Adolescence
Adults should take 50-100 grams of activated charcoal powder mixed with water for a one-dose treatment. Children 1-12 should be given 25-50 grams of water. This translates to about 0.25-0.5 grams per lb of body weight.
If poisoning is severe enough to require a course of treatments, then the Mayo Clinic recommends using 50-100 grams mixed with water and then continuing treatment with a smaller dose of either 12.5 grams given every hour, 25 grams given every two hours, or 50 grams given every four hours for adults.
Children up to 13 years of age should be given the first dose of 10 to 25 grams; then, they should be given 0.5-1 gram per pound of body weight every two to four hours.
Although charcoal in water does not taste good, it is essential not to put it in ice cream, chocolate milk, or sherbet because this can decrease the absorptive qualities and make the treatment less quick or effective.
With any case of poisoning, you should seek formal medical treatment as soon as possible.
The Poison Control Center has a lot of information and a 24-hour number to help. They are an excellent resource for advice and support.
Source For Dosages: The Mayo Clinic
3. Make Your Own Gas Mask
Note: This mask can help you greatly but is not a replacement for a real gas mask. It is much better than nothing and can allow you to minimize exposure and damage to volatile organic compounds and environmental pollutants.
What you need to get started:
- 2-liter soda bottle
- Soda can
- Activated charcoal
- Rubber bands
- Duct or medical tape
- Cotton Rounds Or Stuffing
- Scissors
Instructions Are In The Video Below
4 . Treat insect bites and stings, including particularly venomous ones!
You will often experience conditions that expose you to stinging and biting insects and other animals during a survival situation. For bites and stings, mix a capsule of activated charcoal with 1/2 tbsp coconut oil and apply; place this inside a covering to create a charcoal poultice.
It is impressive that you can treat snake and spider bites as well.
Very venomous spider bites like the Black Widow and dreaded Brown Recluse can be treated by creating a larger amount of the capsule and coconut oil mixture.
You are going to want a large wrap like an ace bandage.
Remove after 2-3 hours, rinse the area, apply a fresh mixture, and wrap.
5. Treat Stomach Flu
It can be used for treating various forms of Gastroenteritis and is very effective.
For more, see our post about using activated charcoal for stomach bugs.
6. Treat Tooth Infection
In the ideal world, we can all go to the dentist for professional treatment at the first sign of a tooth infection. But not all of us can afford a dentist, and there are plenty of situations where you might not be able to get to a dentist for days or even weeks.
For these situations, you can use activated charcoal for tooth infection treatment.
Where to Buy Activated Charcoal
It is easy to order activated charcoal online, and it is not even that expensive.
But it can become a lot harder to get even basic things during a survival situation. Here are some links if you don’t want to or can’t make activated charcoal.
Also see here for more on the best activated charcoal brands.
A few things to remember when using activated charcoal
Activated charcoal can interact with some medications
Double-check your prescriptions to see if they interact with activated charcoal. This is very important.
While charcoal is excellent for detoxifying, you want to ensure you care for other aspects of your health.
The Mayo Clinic has a list of drugs known to interact with activated charcoal, but you should ask your doctor or pharmacist about using activated charcoal if you are taking prescription medications or have any ongoing health issues.
Charcoal stains like crazy
Many people choose to use charcoal capsules because it avoids the risk of staining anything unless you break one open. It also makes knowing your dosage level for a given remedy or compound very easy.
A little goes a long way
Activated charcoal is concentrated stuff, so remember to use it sparingly.
This also means that a small stash can take you through a lot. Having 10 lbs of activated charcoal could also put you in a valuable bartering position because it has many uses.
Do you have any experience using activated charcoal in a survival or off grid situation? Please share with us in the comments below!
Hi, late to the party, but better late than never yeah?
Question: as the AC can be ingested, does the Calcium chloride need to be food grade? Or can I use (the less expensive) pool calcium?
Thank you
M.
Hi, how much ground charcoal do i add to the pickle crisp and water?
Just gradually add the charcoal until a spreadable paste has formed. It will be a bit like a thick toothpaste.
You can get AC in the aquarium section of pet stores, you will have to crush it yourself (coffee grinder might work… or get destroyed. Hammer sounds fun.)
On a side note: Activated carbon/charcoal doesn’t absorb, it adsorbs. Things attach to it, it doesn’t take things inside.
how exactly do you test if the AC from a shop is actually activated? any advise/
Hmmm… That’s a tough question. I’ve never come across anything that looked like “fake” AC. It would probably have a weird taste or residue. So long as you aren’t buying from generic Chinese brands, you should be fine. But you can contact the brand and ask if they do any third-party testing. Good brands will send you the test results.
Vinegar , will react , bubble 🙂
thanks man. great illustration . however I didnt get the exact quantity of powdered charcoal that was mixed with Cacl solution. or is it 100grams too
“slowly add the calcium chloride solution to the powdered charcoal and mix until a spreadable paste has formed. Drain any leftover solution.” In other words, you might end up with some left over.
If you watch the video, you can see that he just used enough solution to create a paste out of the charcoal powder. You may have leftover solution depending on how much charcoal you have.
Apparently, we don’t have an oven. Can we dry it under the sun as an alternative?
nah prob not enough heat just dig a good sized hole and make a fire use a grate (can use one from an oven or firepit grate) and cover while still allowing fire to get oxygen
I have had two dogs get into rat poison, (the little green pieces in a box). First I gave them hydrogen peroxide to make them vomit, and when they quit vomiting green goo I gave them charcoal water to drink. After the first incident, I went to the vet and she said I gave exactly the right treatment. Both dogs survived just fine.
As for chocolate eaten by dogs, I am not so sure charcoal would help. There are websites that give dog weight charts and how much chocolate they can tolerate without harm. My dog ate 12 brownies and was just fine, she is 60 lbs. pounds.
My small dog ate good quality human chocolate last Easter at well above the acceptable level. We fed her an activated charcoal capsule straight off and tried extra in the next two days. (Not sure THEY went down!) She seemed to have no reaction except being a bit restless the first night.
That was good first aid on your part. 🙂 Most people or animals don’t have any reaction to activated charcoal. It’s really something that IMO everyone should keep at home just in case.
Is there anything in pool calcium increaser that would preclude it from use in making AC? I noticed many of the brands available are 97% or more NaCl….anyone know whats in the other 3%?
I may have missed it but I don’t see the amount of CaCl/water mix to add per pound of charcoal here. What is this proportion? Is it that you should add however much makes it a paste consistency?
I used some AC capsules not to long ago when my 5yo snacked on poisonous berries (she thought they were blueberries..) I made her eat a capsule and we immediately went to the ER. She had no reaction and the ER Doc said that was why. So if you have little kids, keep the capsules around. Getting them to swallow it isn’t pleasant but is better than hospitalization (of course still go to the ER to make sure it was enough)
So I’m seeing that the de-icer is really cheap, like $30 dollars for a 25lb bag or so. Is this an adequate quality of calcium chloride, or would the food grade pickle crisp be more ideal? Also, there are the kinds for brewing available, with 7lbs for around $24 dollars. Please email me with a response so that I might be enlightened as to the right type. Thank you!
The active ingredient may be CaCl but it also has other filler ingredients they do not list. It will work for making activated charcoal but due to the fillers, it may not be as effective as a pure sample. That said be careful you may accidentally buy one that uses MgCl and while that may make activated charcoal as well it is more reactive and dangerous to handle.
Great info Bair – thanks for sharing.
How would you embed charcoal in to cloth to replace air filters?
Dude, for a cheap alternative to calcium chloride, just use non-iodized table salt (NaCl —sodium chloride). 1:1 ratio of water to salt. The study shows that even 2:1 ratio of water to salt worked but if you want the same concentration of ions as CaCl2, just do a 1:1 ratio.
https://scholarcommons.scu.edu/cgi/viewcontent.cgi?article=1002&context=ceng
Is western red cedar hard enough?
NO. use oak, maple, hickory, pecan.
How about bleach or lemon juiceinstead of the calcium c?
You can also order activated charcoal from ebay,walmart.com as well as amazon.I ordered my big jar from ebay.
Yep available in many retailers.
If I use table salt instead of calcium chloride will the salt from the activated charcoal leach back into the my drinking water?
Don’t think there will be any noticeable difference in the leaching. Table salt is less effective for activation though. See here for more.
If you use table salt instead of calcium chloride,
(1) just make sure it is not iodized
(2) need to make the solution 50% NaCl instead of 25% CaCl2 because Calcium Chloride provides twice as many ions.
Ok so I had no other salts than NaCl so I made an heavy solution of that and used it to make the charcoal into a paste.
Following the 24hours, I went ahead and washed it in distilled water…
instead of drying it first…
Have I messed it up? How can I tell if its properly activated?
Thanks so much for your help
The drying is necessary and helps with the final filtering process.
In the old days, people would put grape leaves on top of the pickles to make them crispy. Do you think you could dry the leaves and crumble them, to use as the calcium chloride, in a survival situation?
Calcium Chloride is a chemical compound, as far as I can see grape leaves contain none of this so it won’t work. If anyone know different please post here.
Grape leaves and oak leaves are used in pickling for the tannins instead of the calcium compound recommended here. Both make pickles crisp, but through different chemicals. Hope that helps 🙂
Awesome, thanks for the clarification. Very useful to know in a crisis situation.
Thanks so much! I am using activated charcoal in a soap recipe but I will keep a stash for an emergency. I hope to never need it!
How did you powder your charcoal. I demolished my food processor in this process. All in the name of diy! 🙂
Smashing with a hammer works best and very satisfying!
I placed a variety of large round river stones in a cement mixer with the lump charcoal. I had to add a little mist of water to keep.the dust down. Too much water and it makes a mess.
Are these black chunks that remain after I burn oak in my rocket mass heater in essence “activated charcoal”? The temps reach upwards of 1000 degrees F. What is minimum temp required?
Sounds like what you have there is regular charcoal. This can be turned into activated charcoal by following the steps in the article.
Thanks for that information
Ho there
I did your recipe and its a great outcome.my question is,how donyou make a charcoal filter for a cloth face mask? I’m struggling here. Thank you
Activated charcoal is great for pollution (in fact, it’s one of the only ways to remove chemical pollutants from contaminated water). Unfortunately, it isn’t effective against viruses. It would be good for a pollution face mask, but not for a pandemic. If you need an N95 mask and can’t get one, we recommend this solution instead: https://www.primalsurvivor.net/homemade-n95-respirator-mask/