Making Nitric Acid Without Distillation?

For those that dont know the ions,electrons can pass through the clay pot but no liquid can pass through the clay pot wallls some use a sponge but a clay barrier is much better filter.

Why the copper electrode turned black: Red clay has a ton of iron(III) oxide in it which reacts with nitric acid. As quickly as you produced nitric acid it was turning the iron(III) oxide into iron(III) nitrate. You were then performing electrolysis on the iron(III) nitrate, resulting in nitric acid in the pot and iron(II) oxide (black) moving across the "membrane" and depositing on the copper. The reason the bath turned yellow is because the iron(II) oxide will somewhat readily turn back into solvated (or eventually suspended) iron(III) oxide. Almost all of the energy of this process went into dissolving the clay pot. Also nitric acid is really quite volatile, like hydrochloric acid, and will just disappear into the atmosphere. A decent cover over the pot would have prevented this. I've had better luck with using graphite fiber arrow shafts as electrodes than compacted graphite. They don't degrade at all really but their electrical resistance is quite a bit higher.

I've been looking for an alternative way to make ammonia... nice to see this....

New favorite Youtuber!Love your vids man keep it up!

This is going to be great for my diy lab thank you so much

I appreciate and admire folks that have the balls to admit (like you) when they’re wrong. Unlike the myriads of PhD’s in chemistry from the University of YouTube commenting and talking shit. Great video and it forms a great basis for us the other half who are not PhD’s with a degree. 😅

As a general note for others, anode wear can be mitigated by controlling the current density the anodes see. A starting point for graphite I like is around 15 mA/sq. cm. On little cylindrical anodes like these though, this reaction would be taking weeks. I'm using blocks that are a few hundred square centimeters. I think that Scrap Science is just willing to let the wear happen to get reasonable reaction speeds.

Wonderful! I've been purifying saltpeter which had been crystallizing on a wall of a former pigsty for a while now and I've been looking for something to do with it! I also wondered what would happen if I were to electrolyze it so yeah, good thinking I guess.

I finally found an improved but more lengthy process use a copper anode to produce copper nitrate and continiously remove KOH from the cathode compartment. make the porous pot area the cathode compartment. after you obtain copper nitrate crystals from the anode chamber you then run a seperate diapragm cell electrolysis run where you use graphite as the anode and steel or graphite as the cathode and you will produce copper metal in the cathode compartment which you can remove to totally remove and ions in solution to get a very high concentration of Nitric acid. the cathode compartment ph may drop after some time so a tiny bit of sodium hydroxide may help keep it from becomming acidic if you are using steel as a cathode otherwise if its graphite then there is no problem there. This method works for sulfuric acid too but sadly not hydrochloric acid the copper/iron 2 chloride just gets electrolyzed into chlorine sadly

I must say this guy rly makes science with scrap. Nice work

I love just being part of your journey into amateur chemistry by watching your videos. I do a lot of chemistry which I should create more videos of like you. I'm most obsessed with extracting elements from rocks and minerals, which is actually quite dangerous because of the many regularly encountered unknowns. It's a bit scary having to treat the hazmat as I've identified arsenic and thallium from ores I've dissolved in acids. God only knows what else I have in my bucket of various sealed unknown product containers.

Couple of points which may help out. The ionic exchange is being drastically limited by the lack of variable voltage and the distribution of current across the anode and cathode. By this I mean when current is low because of the lack of electrolytes in the distilled water it helps to increase the voltage a little to get electron excitement working quicker. When current starts flowing you can then reduce the voltage well below 12vdc. This is slower but it stops cathode and anode annihilation. Professional electrolysis is usually done at about 1.5vdc to avoid cathode/anode annihilation but it also involves better separation materials rather than clay. The shape of the anode and cathode are critical for even current distribution through the solutions otherwise you'll annihilate your equipment. Instead of dropping the anode and cathodes into the solution vertically and creating a concentration in one particular area, consider horizontally mounted rods. Take the graphite rods and drill 4 holes in them evenly spaced half way through and insert graphite pegs into the holes. Then split the source wire for the cathode into a 1 into 4 configuration and the same for the anode, connect each wire to each peg. This distributes the current and voltage across a larger surface area and increases ionic exchange significantly. Because you have a greater surface area to play with, current can be increased without causing too much damage to the graphite. Voltage can also be increased accordingly because current and voltage are distributed evenly and voltage nodes will not appear on the graphite. Pulse width modulation is also a great option for this type of work, look into that.

I gave this experiment a try, using two small clay pots and a couple of platinum electrodes. Both were the platinum-plated expanded titanium type measuring roughly 4 square inches. I started with a dilute solution of 100G of KNO3 in about 2.5 liters of distilled water, and distilled water in the red clay pots. I used an adjustable digital-display power supply capable of limiting both current and voltage. I set initial voltage to 8V without a current limit. The anode side became strongly acidic in a very short time once the current ramped up; and the cathode side very strongly basic. My yield of very dilute nitric acid appeared to be fairly pure but with a pink tint probably caused by the material of the pot, and similar in ultimate quantity to yours, after about 40~45 hours of electrolysis. I used the opportunity to experiment quite a bit with voltage and current limits, so it's not possible to give better than a ballpark account of those parameters; I'd say most of the electrolysis was conducted at around 5V and 200mA. I found that if I limited current to 100mA, voltage tended to stabilize at about 3.9V with minimal gas production at the electrodes. Higher current got higher voltage (unless it were limited) and a lot more gas. I stopped the process rather early. I'm sure I did not consume all of the 100grams of KNO3 with which I started. I also boiled down a large volume of water taken from the cathode side, which yielded a gram or so of what must be fairly pure KOH, which of course refuses to dry fully over moderate heat. Incidentally the cathode side didn't appear to lose a significant amount of water. Likely because my KNO3 wasn't very pure, the KNO3 solution that was NOT inside either of the pots became slimy and cloudy, with a pH of about 9. The KNO3 had come from stump remover, so it contained unknown anti-caking agents. This, and my desire to move on to boiling down my products, prompted me to end the electrolysis early. So I can't really assign anything remotely like a percentage yield. Presumably this method would produce copper nitrate if a sacrificial copper anode were used. I'm thinking there's a chance that rather than liberating a lot of NO2 as happens when copper is directly added to nitric acid, the NO2 might have a chance to go into solution and thence produce the metal nitrate more efficiently. I'm going to give that a try next. I'll use much purer KNO3. Hopefully the process itself will provide a means to know when the electrolysis is done. I would expect the copper to stop eroding when the KNO3 has been consumed.

Thanks for your effort and resource

Found platinum anodes that test as platinum (platinum coated titanium) for 13 USD - 3x4 inch mesh anode with handle. It is more effecient and cleaner, but works great. Carbon rods are my personal second to that one.

Nice video!!

the video i wanted thank you!!!

Great upload as I'm getting back into it so I can stay home and be a chemist 👍 Now is the pot is the semi-permeable membrane? Thanx💖

You can use iron anode in KNO3 to make Fe(NO3)3 and make KOH in the cathode compartment. Then take the Fe(NO3)3 solution and distill HNO3 off leaving Fe(OH)3 in the distilling flask.

There's definitely ammonia made in the cathode side. I used a platinum coated electrode on the anode side and steel on the cathode side and calcium nitrate instead of potassium nitrate. I'm glad I kept my garage well ventilated because it smells horrible.