Will post some CO tests this monday

[IndictEvolution]

Disclaimer: Do not attempt this method if you cannot do it far away from others AND plaster large warning signs on the vehicle. You will end up harming others.

Haven't looked much, but I'm sure there's already been a good amount of discussion on this specific method, but regardless I'll be doing some tests to see what PPM of CO is reached in my car by mixing formic and sulfuric acid. This will be compared to what the stoichiometric calculations say should be produced. I'll probably preheat the sulfuric acid to 80 C beforehand to speed up the reaction. I am using 95% formic acid, so there's not much water present in it to heat the reaction much initially. I did see one post relating to this talking about scrubbing the output of this reaction to reduce formic acid fumes, and I think this would be a good idea, however it is probably a lot easier for most people to just use a half piece respirator and a 3M acid gas cartridge, which is my eventual plan. Your eyes may still burn from the formic acid fumes, but you can close them. Anyways, if you're interested, look out for my post on moday. Will probably be around this time.

 

[Intoxicated]

I'll probably preheat the sulfuric acid to 80 C beforehand to speed up the reaction. I am using 95% formic acid, so there's not much water present in it to heat the reaction much initially.

Don't you think that the reaction could go too vigorously, leading to overflow? Considering that the reagents will likely be mixed in large amounts, the produced heat could be dissipated not fast enough as needed to prevent a disaster. Stopping that reactor forcefully in order to save the car's interior would be rather difficult then.

I did see one post relating to this talking about scrubbing the output of this reaction to reduce formic acid fumes, and I think this would be a good idea, however it is probably a lot easier for most people to just use a half piece respirator and a 3M acid gas cartridge, which is my eventual plan. Your eyes may still burn from the formic acid fumes, but you can close them.

I wonder how much acidic fumes could be produced in a similar reaction between concentrated sulfuric acid and sodium formate. The salt must be much safer to handle than a highly corrosive fuming liquid acid.

 

[locked*n*loaded]

Looking forward to seeing your results. Someday, hopefully not too far out, I hope to do the same thing with CO generation by means of charcoal in a tent.

 

[IndictEvolution]

Don't you think that the reaction could go too vigorously, leading to overflow? Considering that the reagents will likely be mixed in large amounts, the produced heat could be dissipated not fast enough as needed to prevent a disaster. Stopping that reactor forcefully in order to save the car's interior would be rather difficult then.

I wonder how much acidic fumes could be produced in a similar reaction between concentrated sulfuric acid and sodium formate. The salt must be much safer to handle than a highly corrosive fuming liquid acid.

I guess the main concern would be CO being produced too quickly, causing foaming instead of controlled bubbling. To be clear, this will be a relatively small test in the car (5ml and then 10ml). I'll test beforehand to see what temperature the sulfuric acid should be preheated to produce CO at a sane rate. I will be pushing it though, so I'll probably recommend people use a container that only fills at most half way when all reactants are added.

I did think about using sodium formate, but I just didn't like the idea of there being some intermediate reaction, even though it would probably work just fine. I'm personally not worried about my own safety, and don't worry about dangerous chemicals. Don't take that to mean I'm careless or stupid, I'm just not terrified of risks like most people have been programmed to be.

 

[pthnrdnojvsc]

nobody has documented any test results for the formic acid method to generate carbon monoxide.

So this will help anyone wanting to use that method

i uploaded the GULPS carbon monoxide generator video . I put the link to the video in PM

50 ML of formic acid reaction with 150 ML sulfuric.

i can't tell if he is heating the reaction or not he's got it on top of something , can't tell if it is a heater?. but it's creating co really rapidly 1 liter a minute around 16? liters in 10 minutes or so.

 

[Intoxicated]

To be clear, this will be a relatively small test in the car (5ml and then 10ml). I'll test beforehand to see what temperature the sulfuric acid should be preheated to produce CO at a sane rate.

The results produced with 5ml + 10ml may not scale well on greater amounts of reactants, unless a vessel of a proper shape is chosen or other measures to prevent overheating are taken. I haven't ever dealt with formic acid, but I noticed that in general, exothermic reactions in liquids with emission of gases may become too vigorous very easily when big amounts of reagents are mixed. This phenomenon can be explained by a significantly worse rate of heat dissipation.

The origins of the problem with heat dissipation for increased volumes can be viewed in two ways. On one hand, increasing the volume of a vessel without changing its geometrical shape decreases its S/V ratio (surface area divided by volume) proportionally. For instance, if you double the diameter of a spherical flask, its volume increases 8 times, but the surface area increases only 4 times. Adding 8x amount of the reactants will likely initially produce heat at 8x rate, but this heat will have to be dissipated through a surface that is only 4 times greater. On the other hand, it's easy to notice that the heat produced by a portion of the liquid mixture somewhere at the center has to be transferred to the surfaces on bigger distances when the linear sizes increase.

Worse heat dissipation implies worse cooling of the mixture. This leads to elevation of its temperature in an exothermic process, that speeds up the reaction, which then produces heat at an even higher rate, and then dissipating this heat properly becomes harder. This vicious circle may eventually boost the reaction rate to an enormous degree.

Therefore, some decent attention should be paid to proper cooling of the mixture. It can be achieved either by choosing a special vessel whose shape would allow sufficiently good heat dissipation or by using some effective cooling agent outside.

I did think about using sodium formate, but I just didn't like the idea of there being some intermediate reaction, even though it would probably work just fine. I'm personally not worried about my own safety, and don't worry about dangerous chemicals.

It's not just a matter of safety in the sense of the risks of getting injury. Even experienced chemists allow acid spills sometimes. Spills of a volatile acid with corrosive and very irritating fumes are often nasty, regardless of whether they pose any somewhat serious threat to your health. I suspect that the salt could be way more handy to work with.