Activated charcoal might be something you’ve heard of, but maybe you’re not entirely sure what it does or what it can be used for. We’re probably all aware of that old home remedy where you eat some burnt toast to soothe a bad stomach, but that might be the extent of your knowledge about the usefulness of charcoal (or more specifically, carbon) when it comes to survival. Activated charcoal, which is also known as active carbon, is chemically only a few steps away from burnt toast, but it has many more uses from a survival perspective.
Activated and active are interchangeable here – activated charcoal is active charcoal. Activated charcoal is one form of active carbon (really, all carbon is the same, but you might call it something different if the “source” of the activated carbon was something other than hardwood).
Activated charcoal can be used to filter water or to make DIY gas masks. It can be used as a makeshift antidote to poisons. You can use it as a salve for insect bites even helps with venomous bites). Or you can just use it to alleviate a regular old stomach bug, food poisoning, or even a hangover. It had a multitude of survival (and everyday) uses.
In fact, you’re probably already using it. If you have a water filter at home, chances are it uses active carbon as a filter. Same goes with some air purifiers.
We’ll be completely honest with you. Making activated charcoal at home can be quite an arduous process. This is one of those survival skills where you want to learn it, try it once or twice, and have it in your back pocket just in case – but as long as society hasn’t collapsed, we generally recommend you buy activated charcoal rather than make yourself.
That being said, making it at home is definitely cheaper, and in a survival situation, you might be forced to DIY it. That’s why it’s important to learn the method now – so you know how to do it if the need arises.
We’ll teach you how to make activated charcoal, then go over what exactly it is, what it can be used for, and how it’s different from regular charcoal.
How to Make Activated Charcoal
To make activated charcoal, first you need “regular charcoal”. You can either buy it and skip about half of the process, or you can make your own charcoal.if you’re buying it, it’s important to note that the briquettes that are the most common type in shops wont work for this. Mass manufactured charcoal frequently has chemicals that are added during production, and these chemicals get in the way of what you want to achieve, which is essentially pure carbon.
Consequently, if you’re buying your charcoal, look for lump charcoal (i.e not briquettes) and make sure what you’re buying is free of added chemicals. This might be advertised on the bag as “100% natural”, “all natural” or “chemical free”.
Important note: This is definitely something you want to do outdoors,especially if you’re making your own charcoal. Burning down your own charcoal from hardwood will set off every single smoke alarm in your house, and the charcoal powder that you’re going to make will get everywhere and stain everything. Only do this outdoors or you’ll probably regret it.
If you do end up buying your charcoal you can skip straight to the second part of these instructions:
Making your own (regular) charcoal
To make (regular) charcoal, you’ll need:
- A bunch of hardwood
- Something to split or cut the hardwood
- A big pot
- Somewhere to start an outdoors fire or a decent sized grill.
Step by step instructions for making charcoal from hardwood
- Start with some kind of hardwood, like maple, oak, or walnut. You want to avoid soft woods like pine and woods that are resinous like cedar. Remove the bark (to the extent that you can), then split and cut your wood as necessary to get small chunks of wood no larger than 3 or 4 inches at the most.
- Get a big pot that can fit all your wood into it, along with a lid that’s snug but not completely air tight. Make sure your pot can handle extremely high temperatures. You can also use a metal barrel if you’re doing a large batch.
- Build a fire underneath the pot, or put your pot on a grill grate above a fire. This fire needs to stay active and burning for a good 4 or 5 hours.
- The goal here is to heat the wood in the pot without setting it on fire. A fire will produce mostly ash, but heat without the wood catching fire will produce mostly charcoal. That’s why we have the lid on – so the wood doesn’t have enough oxygen to be set aflame, but gets hot enough from the fire underneath to turn into charcoal.
- Once your pot has been on the flame for about 4 or 5 hours, remove from the flame. Once your coal has cooled enough, rinse off the excess ash, drain, and leave to dry overnight.
- Upon opening the lid the next day, all your wood should be blackened into charcoal.
To make your own activated charcoal
To make regular charcoal into activated charcoal you’ll need
- A hammer or mallet
- A blender, food processor, or mortar and pestle
- A sieve or strainer
- Stainless steel or glass bowl/pot (NOT aluminum)
- Heat proof gloves or oven mitts
- Calcium Chloride (or zinc chloride, or lemon juice)
- Coffee filters or kitchen towels
Step by step instructions for turning (regular) charcoal into activated charcoal
- Pulverize your charcoal into powder. You can do this by putting your charcoal into a sealed bag of some sort and smashing it with a hammer. To further pulverize, you can use a blender or food processor (or if you’re really a glutton for punishment, a mortar and pestle). Essentially you want as much powder as possible. This isn’t 100% necessary, but basically the finer your charcoal, the better it will filter.
- To filter further, use a strainer or sieve and sift your charcoal powder to filter out the larger pieces. You can then choose to reblend or re-smash the larger pieces and sift again if you think it’s worth the effort.
- Transfer your charcoal powder into a stainless steel or glass bowl. Warning: Do not use aluminum for this process. Aluminum can react with the calcium chloride you’re using and you don’t want that.
- You’ll want heat proof gloves or equivalent for this step. Make a solution of 3 parts water to 1 part calcium chloride. e.g if you have 600 ml of water you want 200 grams of calcium chloride. Do the same with zinc chloride, or if using lemon juice, just use it straight (e.g 800 ml of lemon juice would be a replacement for the 600ml water and 200 grams calcium chloride solution). You want enough solution to be able to cover your charcoal powder completely.
- When mixing the solution, be careful. Combining the two creates a chemical reaction that can release heat – whatever vessel you’re using will get quite hot.
- Add the solution slowly to your charcoal powder so that it is covered in liquid. Mix it so it turns into a paste.
- Cover the bowl or pot that the mixture is in and leave to dry for 24 hours.
- After 24 hours, drain the mixture, then rinse with distilled water at least three times and drain again. The best way to drain is to put coffee filters into a mesh strainer/sieve.
- Once drained of most of the moisture, the last step for activated charcoal is to either put it in the oven or “cook” it on a stove. For the oven, set the temperature to 230 F and leave for 2-4 hours, or until the charcoal is not wet or moist to the touch at all. For the stove, use the lowest heat for the same amount of time. The goal here is basically to remove all moisture.
- You’re done! Store your activated charcoal in a water proof and air tight container and save it for the apocalypse (or the next time you get food poisoning).
Regular Charcoal vs Activated Charcoal – What’s the Difference?
Regular charcoal is just carbon that hasn’t been processed. It’s charcoal that hasn’t had its absorption capabilities maximized. Charcoal can still absorb stuff, but isn’t anywhere near as efficient as activated charcoal.
Activated charcoal is charcoal that has undergone a process to maximize its ability to absorb. It’s like charcoal on steroids. It absorbs more efficiently and thus is a better material than filtration than regular charcoal.
What is Activated Charcoal Exactly?
The reason why burnt toast works as a remedy for a bad stomach is that carbon is pretty good at absorbing stuff. If you have bad stuff in your body that’s making you sick, eating carbon (the fully black bits of burnt toast) means that you’re putting something in your body that can absorb the bad stuff.
Charcoal is basically just another word for carbon. In scientific terms, activated charcoal is carbon that has been processed to maximize its surface area. The chemical process described above (mixing the calcium chloride solution with charcoal) creates tiny pores in the carbon, massively increasing the surface area. The increased surface area maximizes its absorption qualities.
When manufactured commercially, different chemicals other than calcium chloride are often used, but the goal (and effect) is the same – activated charcoal is charcoal that has been processed with some kind of chemical that increases its porousness, and these pores increases the surface area which increases its ability to absorb other stuff. Essentially, you’re turning your charcoal powder into millions of teeny tiny little sponges that are great at soaking up bad toxins and unwanted chemicals, which is why it’s both great for filtering water and great as a home remedy for a stomach bug.
Why Make Your Own Activated Charcoal?
Well, the first reason why you’d want to make your activated charcoal is because it’s cheaper than buying it. One pound of activated charcoal is roughly $12 – whereas regular charcoal in a 20 pound bag costs ~$38. Even factoring in the cost of the calcium chloride, activated charcoal is still probably four of five times more expensive than regular lump charcoal.
However, if we’re being honest, making your own activated charcoal is a pretty dull, labor intensive process. It’s a whole weekend’s worth of work – a weekend that you could be spending doing something else. Unless you’re passionate about charcoal-related projects (or maybe you want to do an easy science project with a kid), there’s no real reason to make your own activated charcoal unless you’re on a severely limited budget.
The real reason we’re writing about this topic on Secrets of Survival is because it’s a useful survival skill that you should know.
A world where you can’t easily buy activated charcoal is probably the same kind of world where doctors aren’t going to be easily available, and where you might be coming up against food poisoning and venomous insects more frequently that you do now. In a longer term survival situation or post apocalypse scenario, activated charcoal would be an extremely useful thing to have… and most people will have no idea how to make it.
For this reason, we encourage you to learn how to make it, and try to make it at least once or twice. Once you’re aware of the general steps, go ahead and buy it when you need it. But it’s smart survival planning to add the skill to your arsenal.
Another reason why you might want to know how to make activated charcoal is because it will probably become a useful barter commodity in a post-collapse scenario. Those who don’t have useful resources won’t be able to trade for things like food, medicine, and ammunition. If you know the process behind activated charcoal, you’ll always have a useful resource at your fingertips to barter or trade with.
What can Activated Charcoal be used for?
1. Water filters
Probably the most useful thing that activated charcoal can do from a survival perspective is filter water. If you boil water, then filter it with activated charcoal, you can pretty much guarantee that your water is safe to drink – in a crisis situation, this could mean the difference between life or death. Just imagine – you’re in a crisis situation and running for your life, but you’re crippled with a bad stomach because you drank some unclean water.
To make a water filter out of activated charcoal, all you need is some coffee filter-like material (kitchen towel would work as well) and an empty soda bottle. Cut the bottle in half and discard the bottom half. Plug the mouth of the bottle with your coffee filter or kitchen towel, then spoon in a generous amount of activated charcoal into the half soda bottle that you’ve kept. That’s it – you have a makeshift water filter. Essentially all you need is something that has a narrow hole on one end and a wide mouth on the other. Plug the narrow end with a material that will allow water through but that will block the charcoal from falling through. Then add the charcoal, and that’s your water filter.
Even easier than the above (although not as re-usable)… Just use a sock! Put some activated charcoal in a clean sock (don’t use anything that smells like detergent), and you’ve got your super-improvised water filter. Just pour water through the sock and have a vessel underneath.
2. Gas Masks
Did you know you can make an improvised gas mask out of nothing more than activated charcoal and some household items? This is what you need:
Beer or Soda Can
The actual construction is pretty simple, although hard to describe in words, so we won’t try. Instead, you can watch the video below to see how it’s done.
3. Remedy for Poisons/Toxic Substances
First thing – if you’ve ingested something poisonous or toxic, go to the hospital or call an ambulance immediately. Activated charcoal can help, and might even save you, but that doesn’t replace medical care.
Now, if you’re in a post-disaster world where medical care isn’t available, then you’ll have to take your chances with the activated charcoal.
First things first – never give activated charcoal to a baby under 1 year old. It can be dangerous for their health.
If you’ve ingested a toxic or poisonous substance, try to get the activated charcoal in your body ASAP, ideally within 30 minutes of when you consumed the poison.
One “dose” of activated charcoal for adults is 50-100 grams of activated charcoal mixed into water. For children, half the dosage to 25-50 grams. A good rule of thumb is about a quarter of a gram to half a gram of activated charcoal per pound (in terms of body weight) for a person.
If the poisoning is severe and treatment is required, (for adults) you can continue ingesting 25 grams (again, mixed with water) every two hours. For children, do 10 grams every two hours instead.
Now, it should be obvious that charcoal mixed in water tastes pretty awful. Kids in particular might be reluctant to drink it – but it’s important that you only mix the charcoal with water and nothing else. If you mix the activated charcoal with another substance, the charcoal will absorb stuff from that substance and won’t be able to absorb as much of the poison, making the remedy less effective.
Again, do not do this as a replacement for proper medical care. Use this in addition to medical care – for example, if help is on the way. Alternatively, if you’re caught in a crisis scenario and there’s no medical care available, activated charcoal might be your best beat to beat the poison.
4. Treating Bites (including Venomous Bites)
Activated charcoal can also be used to treat insect bites, and can even help alleviate venomous or poisonous bites from dangerous insects and other animals.
Simply mix activated charcoal with coconut oil or water to make a paste, then spread on the bite.
For more serious bites, including poisonous bites from spiders or snakes, use more of the activated charcoal paste, slather it on generously, then wrap the wound with bandages or first aid dressings. Change out the bandages every couple of hours by rinsing the affected area, reapplying fresh activated charcoal mixture, and re-wrapping with fresh bandage.
Obviously this could prove extremely helpful in any wilderness survival scenario.
We’ll reiterate that activated charcoal is not a replacement for medical care. If you get bitten by a poisonous spider or snake, seek treatment immediately.
5. Settle upset stomach or food poisoning
Much like the poison situation above, activated charcoal can help settle an upset stomach and can reduce the symptoms of food poisoning or stomach flu. Use similar dosages as described above in the poison section to calm an unsettled stomach.
6. Air purification
To help ward off unhealthy or toxic fumes, smog, and air pollution, you can put some activated charcoal in a lightweight cloth bag of some sort and it will help with air purification. Obviously it won’t purify “all” the air with this setup, but it will make a difference. To increase effectiveness, put the improvised air purification filter in front of a fan (make sure your charcoal doesn’t blow everywhere).
7. Hangover Cure
Some people also say that activated charcoal is an effective hangover cure. The evidence is iffy, but some people swear by it. This is a survival site so we don’t care either way, but we’ve included it here if that’s of interest to you.
Where to Buy Activated Charcoal
If you don’t want to make your own, you can buy activated charcoal online – it’s pretty widely available on Amazon and other online retailers.
Many supermarkets/grocery stores might have activated charcoal somewhere on their shelves. Pharmacies definitely carry activated charcoal in pill form, although buying it pill form can add up very quickly. Home goods stores will sell water and air filters that already have activated charcoal built in.
If you just want the powdered activated charcoal itself, buying it online is probably your best bet for a decent price.
A Few Additional Tips About Using Activated Charcoal
Activated charcoal can get extremely messy extremely quickly. It stains almost everything it touches and is pretty hard to clean, so be careful when handling it, especially indoors. Unfortunately, activated charcoal is not a remedy for ruined tablecloth or an angry spouse. That’s one of the benefits of the capsules/pills that contain activated charcoal – they’re guaranteed to be mess free.
Activated charcoal can interfere with medicines (it absorbs stuff, good and bad). If you’re on any kind of prescription, be aware of potential interactions and check with your doctor whether activated charcoal is safe for you to ingest.
A little bit goes a long way – don’t overdo it. Activated charcoal is pretty highly concentrated, so when you do need to ingest it, make sure you’re keeping to the recommended dosages.
If for some reason your activated charcoal gets wet, you can always re-dry it in an oven at 230 degrees.
If you do end up making a batch of activated charcoal for survival purposes, there’s no need to ever dispose of it. Keep it on hand as both a useful resource and a potentially very valuable barter commodity.