How To Make Potassium Nitrate (Rocket Fuel)

This is my most requested video ever. Today, I'll be showing you how to turn wood into potassium nitrate. And after we've succeeded in making it, I'll take this a step farther by showing you how to make fuse and homemade rockets. And to make things harder on myself, but easier for you throughout the entire video, I'll only be using household appliances. Like I said for this project, you're going to need to find some wood. You can use anything. I'm outside searching for some sticks. Now, you're also going to need a metal container, but the size of this doesn't matter. I'm just using the same bucket that I did in the homemade metal foundry video. So, we just grabbed all of our wood. Now, let's go ahead and burn it. In the old pickup truck. If you're burning a smaller amount, you're probably fine. But because we're burning so much, I'm going to head on over to a campsite to burn it. So, I left my thermite at home, so I'll just be using gasoline to light this on fire. So, essentially, we just need to turn our wood into ash, and then we'll take our ash out, and that's what has our potassium nitrate inside. Now, this doesn't burn super fast, and that's because there's not enough oxygen. But if you were to poke a hole and then use something like a leaf blower to blow air inside, that would work better. But I can't do that because I said I'm not going to use tools. I tried stirring it up to make it faster, but all I had was these two metal spoons. So, I kind of just burnt my hands in the process. So, it's not entirely burnt, but it's mostly ash. So, at this point, we're going to add a bunch of water to it. As you can see, there is still a lot of coals, but we don't need a whole lot of ash for this to work. So, there's potassium nitrate inside of our wood, and we can extract it by burning it, turning it into ash, and then soaking it in water. Now that our potassium nitrate has seeped out into our water, we need to find a way to remove it. And it's really not that hard. All we have to do is sift, filter, and then evaporate it. Let me show you how I do it. Now, I was using lake water, but since we're filtering it anyways, I didn't really think that it matters. Yeah, you can't see it in there. It's pitch black. Now that all the ash has seeped into our water, it's time to filter it out. For this, I'm going to be using a sieve. Mine's inside of this little metal cup, but you can use anything, like a coffee filter. Typically, you'd burn it until it's full of the ash, but since I burnt so much, I didn't have to. Obviously, the more ash you have, the more potassium nitrate you're going to be able to put inside of your water. Now, to prove that there's actually potassium nitrate in here, we're going to use some pH strips. When I put this inside, it should turn blue or purple. There you go. As you can see, this matches with a 13, so it's heavily acidic or basic. I'm not sure, man. As you can see, this matches with number 14, so it's extremely basic. So, this told us that we have potassium nitrate. Now, we just need to find a way to extract it. So, we're going to need to filter this really well. To do this, go ahead and grab a paper towel and then a plastic cup. Shove a bunch of the paper towel at the bottom and then poke a small hole at the bottom of your plastic cup. So, our filter's made. We're going to go ahead and filter off some of this charcoal water into another cup. For that last step, go ahead and take a mason jar and put the plastic cup inside. Now, when we pour water, it should filter off clean. Now, this is going to stop running because it creates a seal. So, I usually stick something in between it so it doesn't seal. The more paper towels you add, the better the filter is, as you can see in the difference of clarity here. And, I mean, it's not perfect, but as you can see, these are the three stages of filtering. This is the third time I filter it, and it's getting considerably clearer. Now, I'm going to go ahead and pour some of this charcoal water into another cup. I got bored and built a filter tower. Yeah, that's it. So, this stuff isn't perfectly clear, but it's honestly good enough. So, let's go ahead and boil this off. But, before we do that, we need to do something first. After all the research I've done, I've found that you need to add nitric acid. So, I'm going to add a little bit of nitric acid. I'm going to add a little bit of water. I'm going to add a little bit of water. I'm going to add a little bit of nitric acid. I'm going to add a little bit of water. After all the research I've done, I've found that you need to add nitric acid to it. So, we're going to do two different tests. One of them, we're going to add nitric acid, and the other one, we're not going to add nitric acid. But, if we do end up needing nitric acid, I've already built a nitric acid generator in my previous video. So, go ahead and watch that if you need to make some. So, we got both of our mason jars, and to this one, I'm adding some diluted nitric acid. This one will not be having any nitric acid in it. Now that we've done that, all we have to do is just boil down the water. Now we just wait. Let's go ahead and boil this other one. I'm going to be doing it much faster, though. Okay, so this one smells like potassium nitrate, and I can't tell for sure. Now, I always smell my chemicals after I make them, and this smells like potassium nitrate in water. So, I think it might work, but we'll have to test it out to see. After boiling down, you can see that we do have trace amounts of potassium nitrate, but I think adding that nitric acid would have made it work better. And this didn't work. I'm not surprised, because every video that I've watched told me you needed to add nitric acid. So, go ahead and watch the video on how to make a nitric acid generator. It's the last one that I posted. Now, I could be wrong, but right now, there's potassium carbonate in here, and adding nitric acid is what turns it into potassium nitrate. I have no idea if this is true, but I watched some random video by this Indian dude, and that's what I got out of it. Let's go ahead and boil down this solution with the nitric acid in it, and see how much potassium nitrate we get. Okay, it's dark outside, and I'm about to go to bed. Ow! So, after evaporating all the liquid that I had, that's how much potassium nitrate I was able to produce. I don't know for certain, but I'll go ahead and test it out tomorrow. It was a long night, but we finally got all the potassium nitrate from that bucket out. It's not an insanely large amount, but let's go ahead and weigh it all. We have a grand total of 14 ounces of potassium nitrate. So, this method works, but it took me all day, and it's only $3 a pound, so, honestly, I recommend just buying it. Potassium nitrate is useless like this, so go ahead and put it inside of a bag, and then crush it up until it's a fine powder. Now, go ahead and combine all of your potassium nitrate with an equal amount of sugar. So, if this is potassium nitrate, when I mix it with sugar, it should react really cool. This is what they use for amateur rocket fuel. As you can see, we actually got a pretty decent reaction. That's way better than all of the other videos I've seen of homemade potassium nitrate. Their potassium nitrate's way worse than mine. That's just because I'm that cool, I guess. You should subscribe. Now that we've achieved making potassium nitrate, it's time to move on to making our rocket. Now, I already have a tutorial about this, but I've improved the design a lot, and in my opinion, it is the easiest tutorial there is on YouTube. For the body of our rocket, we're going to be using three-fourths inch PVC pipe. I'd also recommend picking up three-fourths inch end fittings. Now, you don't need these little caps. If you don't want to have to buy them, you can just watch my other tutorial. But it makes it so much easier, I recommend just buying them, because you can skip all the hard parts. The general design of our rocket's solved. Now we need to figure out propellant. And we're going to be using the potassium nitrate that we just made. Except I just burnt all of mine, so I'm just going to use the stuff that I bought. You could still use the stuff that you can make from wood, except it would just be a little bit harder and more time-consuming. The actual amount you use doesn't matter until later, so I'd recommend just using as much as you're comfortable with. Our potassium nitrate already works by itself, but if you blend it down, it'll react much quicker. All right, as you can see, it's much more fine and powdery. This is exactly what we need. I'm just going to dump everything into this big green bowl and mix the right ratios of ingredients later. You need to mix your sugar and potassium nitrate at a 75% to 25% ratio. So I'm going to need 78 grams of sugar. Before you use your sugar, you're going to need to blend it up as well. So you have our rocket fuel, now you're just going to need to mix this stuff up. So we have everything done, let's go test it out. If you've done everything right, this should burn really quick. Just like that. As you can see, there's a lot of energy there, but I want to see if there's anything we can do to make it faster. I know that sulfur burns things a lot quicker, like in gunpowder, so my first idea is to add some of this. This is test one with 30% sulfur and 70% rocket fuel. Okay, so that unfortunately didn't work. Now I'm going to try it with 5% sulfur. I accidentally lit it too early, but I feel like it reacts pretty quick. That's just me though. Okay, so we have our repellent, now it's just time to finish the rocket. I went ahead and super glued one of the end caps to the PVC pipe. Go ahead and fill it up with the rocket fuel mixture. Once you've done that, take a stick and go ahead and pack it in as tight as you possibly can. Go ahead and repeat this process until your rocket is completely filled up. Once it's all the way filled up, we're going to need to work on our next end cap. Take a knife and carve out a small hole to fit a fuse. Okay, so as you can see, we've drilled a small hole, and now we can fit our fuse in. But technically, I'm not even allowed to possess this because someone called the cops on me, and now I can't use any fireworks. So I'll show you how to make a fuse. We've actually already finished most of the steps we need to make a fuse. All we need now is yarn and water. Any string should work as long as it's absorbent. I'm actually using twine here. Fill up a pan with a very small amount of water. Add your yarn to the water. Once you've done that, grab your rocket fuel mixture and add it to the water as well. Now turn on the heat and cook it until the water boils off. The rocket fuel mixture should absorb into the yarn, and once it's fully dry, you can use it as a fuse. Make sure to stir this stuff so it doesn't burn. I always have people telling me that making rockets this way is dangerous. And it can be. So here's your disclaimer. All jokes aside, this rocket thrower reacts much too slow to cause any serious damage. I almost forgot. We're going to need a stick for our rocket so it can fly straight. Usually the heavier the stick, the straighter it flies. But if it's too heavy, then it won't take off. For a stick, I'm always using an arrow. Mainly because I think it's just kind of funny. Now a lot of people are always concerned that this is too heavy, but I think it's on the contrary. Because this thing's really hollow and made entirely out of fiberglass, it is pretty light. So this should do the trick for our weight. Our last step is just to tape up the rocket at the end. And now you have a working rocket made literally from wood. That's crazy. For the stand for our rocket, I'm literally just putting it inside of a cup full of water. Okay. Let's light our rocket. Man. I hope this works. Wow. Great. I forgot to drill a hole. Gosh dang it. Well, I'm not surprised that didn't work. And in fact, I knew it wouldn't work because I'm not allowed to light rockets anymore. So I intentionally didn't do the most crucial step, which is drilling a hole through the entire rocket. If you want your rocket to work, you can do that. And if you're confused on anything, go watch the entire video that I made about making rockets. And somehow, I don't even know how, I just showed a picture of wood in my last post. And so many people guessed the correct answer that I was making potassium nitrate. So here's your shoutout. If you want a shoutout in my next vid, tell me what I'm using this acorn for. There's no way. Literally no way. And if you guys are guessing this, like I'm done. It cannot be this easy. And if you want to make potassium nitrate from wood, you're going to need nitric acid. So go watch the video I made on a nitric acid generator, and that'll teach you everything you need to know.