2hrs for acidification of n-Butanol

Topic created by WaPopperBator
on Fri, 25 Apr 2025 at 21:04

WaPopperBator said on Fri, 25 Apr 2025 at 21:04...

Hi-
How long does it take you to add your acid to your alcohol?
To 78ml of n-Butanol, I am adding 46mL of 98% H2SO4. I am maintaining the temp around 1-2 degrees, never going above 3. I'm adding it dropwise with a burette, constantly stirring. It is taking me upwards of two hours to complete this step!
Is it taking everybody else this long? Am I being overly precautious?

When I am done my acidified alcohol is this beautiful shiny viscous liquid. As long as the temp stays below 3 degrees it has no odor.

I've done this batch size multiple times and it has always taken this long. My concern is when I try to scale up. Will this step take even longer?

Dr. Wang said on Sun, 27 Apr 2025 at 06:37...

Hello, my more sophisticated cousin from the North!
If you check my last lab notes post, you'll see my opinion on this variable. I think as long as you're not producing nitrogen oxides, you can go faster. I go about one drop per second, but scaling that up could take ages.
Of course, a larger mass in a larger vessel follows some kind of square rule WRT surface area and becomes more difficult to cool. Still, just go faster and see how it goes. Worst case scenario, you'll have an inferior batch and a new data point.
Now that you've made a few batches, what do you think of your product?
I'm dying to know.

Dr. Wang said on Sun, 27 Apr 2025 at 06:39...

And yes, you want to keep the reaction as short as practical, as decomposition is rapid. You can see videos on YouTube where it begins bubbling before it's even done reacting.

Dr. Wang said on Sun, 27 Apr 2025 at 07:02...

And it's not my intention to dominate these convos. If anyone else has anything to add, please, by all means.

WaPopperBator said on Mon, 28 Apr 2025 at 16:11...

I'm making slow but steady progress. I've determined that I am over-acidifying my mix.
I am going to try the following ratio in my next batch:
1.05 alcohol : 1.10 nitrite : 0.95 acid.
I found it interesting that my waste dump bucket smelled of better poppers than my actual batch, because my waste water also had baking soda in the mix. It corrected the acid imbalance, which lead me to the theory.
I've also added a NaCl brine wash to the process to help break the emulsion and increase yield.
I'm still not producing anything I would share with others. Fingers crossed I get there soon.

Dr. Wang said on Mon, 28 Apr 2025 at 16:58...

For H2SO4, this molar ratio is twice as much acid as you need.

Your 1.05:1.10:0.95 ratio is in moles, correct? The molar ratio for C4H10O and HCL is 1:1:1, so this would be fine, but for sulfuric, it should be 1:1:0.5
That would work out to:
100g alcohol
93g NaNO3
67.5g 98% H2SO4 (or 160g 30% HCL)

https://www.webqc.org/balanced-equation-C4H10O+NaNO2+H2SO4=C4H9NO2+H2O+Na2SO4
https://www.webqc.org/balanced-equation-C4H10O+NaNO2+HCl=C4H9NO2+H2O+NaCl

Is it taking 2 hours of acid addition to keep the temp from going above 3?

-----------
Rambling pontification;
I've done 1-butanol and 2-butanol. My preliminary notes were "not good". Aside from 3-methylbutyl, the only one which was in the 'possible' column the first time around was 1-propanol, though I've only given these other alcohols one or two tries, and as you know, there are many, many variables, so I'm not saying it's not worth pursuing, and everyone responds differently. To underscore this variability, with good precursor, I've had a lot go wrong with the reaction and still get a good product. With the last 3-methylbutyl I just got from Poland, the first vial I made was comparable to what I was making before and was intense, but the vial I made last night from that same precursor overheated initially because I opened the stopcock on the acid too quickly, and the finished product was just so-so.

Excess acid will accelerate decomposition and require washing the product with bicarbonate to prevent odd smells or burning of the nose, but I'm not sure how much of an effect it would have on strength/quality, aside from the decomp of such a long reaction.

Dr. Wang said on Mon, 28 Apr 2025 at 17:05...

Sorry, correction- NaNO2, not NaNO3

WaPopperBator said on Mon, 28 Apr 2025 at 19:34...

So I am WILDLY over acidifying...which explains a lot.
I started with the 1-butanol because that is what I could find. The 1-butanol has a characteristic 'over ripened fruit' and a yellowish color which I don't care for. I also associate the smell of 1-butanol with OTC European poppers I can pick up at sex shops in France.
I have some 2-butanol on its way in the mail. In general, I prefer the experience of 2-butanol when made by the professionals like those at Video Head Cleaner from Chicago. I hope that becomes the base for my product in the future.

My AI assistant made good arguments for using H2SO4, however I'm curious about the HCl. Specifically, having the NaCl waste product is so much easier to clean up. Any thoughts?

Dr. Wang said on Mon, 28 Apr 2025 at 21:50...

Yes, acid is a bit high, which could accelerate decomp over such a long addition period.

Both sodium chloride and sodium sulfate are effectively insoluble in butyl nitrite, so that leaves you with the difference in workup, with table salt being more soluble in water, so using a separatory funnel may be needed with NaCl as opposed to decanting as you might do from sodium sulfite, depending on how sparingly water was used in the reaction. If you wish to use a funnel, obviously just add some water to get separate phases. Both salts will tend to pull *some* water from the product, depending on their state of saturation in the reaction, but a negligible amount considering the dryness that's required.

Okay, a world traveler, right on. Everyone is going to have a preference for 'aroma', effects, etc., either from their earliest experiences/imprint/nostalgia, or what last worked best for them, or what works for their physiology, or what have you, so I am completely open to the idea that not everyone will react to my product the same way I do.
So yeah, experiment!
When was the last time beta testing got to be so much fun?

Kurz said on Tue, 29 Apr 2025 at 04:39...

98% H2SO4 is going to burn out the reaction. You have to add water. Perhaps dilute to 25% to 70% just for reference. Also, H2SO4 is diprotic.

WaPopperBator said on Tue, 29 Apr 2025 at 16:21...

Is anyone else interested in forming a small Telegram or Signal group of chemists for more targeted conversation? wapopperbator@gmail.com

Dr. Wang said on Tue, 29 Apr 2025 at 21:22...

Thanks Kurz. I've mentioned before how the acid is diluted with ice to about 30-45%, but you make a good point. For completeness, I need to start remembering to put links in to the relevant posts to give context for those just arriving.

https://poppersguide.com/forum/15785