Third batch

Topic created by Charlie
on Mon, 8 Nov 2021 at 22:57

Charlie said on Mon, 8 Nov 2021 at 22:57...

Apparatus:

Stirrer with temperature probe holder placed in chest freezer set to -6F. Switched the actual probe holder for a burrette clamp, which holds a 16mm OD/12mm ID, 6" long glass tube for the dropping tube. The reason for the stirrer with probe holder is that it is shorter than a laboratory stand to hold the burrette clamp - freezer height is limited.

The drop tube is stoppered with a drilled rubber stopper. Chemical-grade output tube (3/16" OD 1/16" ID) from the peristaltic pump is fitted into the drilled stopper. The stopper seals the top of the glass tube to create an air gap to get the drops below the surface of the water. This worked very well this time. (The rubber stopper may need to be replaced occasionally because of the acidic environment. Time will tell.)

The peristaltic pump is set up outside of the freezer and the pump’s input and output tubes run through the drain hole of the freezer so that the lid can remain shut. The acid/distilled water is also chilled and sits inside the freezer within a 250mL round-bottom boiling flask, which sits on an 80mm cork ring. The reason for the round-bottom boiling flask is to allow the pump tube to gather almost all of the contents from the vessel and prevent needing a large excess to satisfy the pump from a flat-bottomed vessel.

On top of the stirrer, there is a 64 oz. Pyrex container with a 600mL tall-form Pyrex beaker inside. Water fills the area around the beaker and is frozen overnight with tape holding the beaker down.

Temperature:

Everything chilled overnight to -21C (-6F), including reaction vessel and reactants. Things warmed a bit while setting up.
Dropped 111mL HCl and water over 160 minutes of drop time.

Started at -14C
After 15 min. dropping: -11C
After 30 min. dropping: -10C
After 34 min. dropping: -10C, paused dropping for 10 min. and temp. recovered to -11
After 45 min. dropping: -10C
After 60 min. dropping: -10C
After 75 min. dropping: -10C , paused dropping for 10 min. and temp. recovered to -11C
After 90 min. dropping: -11C
After 105 min. dropping: ? Missed adjusting stirring speed
After 120 min. dropping: -8C, paused dropping for 10 min. and temp recovered to -9C
After 135 min. dropping: -8C
After 150 min. dropping: -7.5C
After 160 min. dropping: - 7C

Conclusion:
Using a beaker is a necessity. It was possible to see the solution mixing much better than with the Erlenmeyer flask. Last batch there were pressure issues because the flask was stoppered - bad decision. No issue this time of brown NO2 in the drop tube from back pressure in the reaction vessel. No NO2 gas covering the walls of the freezer. The reaction seemed much calmer than ever before, very few bubbles at all. Very calm throughout - checked at least every 15 min.

After 90 minutes, had to increase the speed of the stirrer because there was a frozen layer of small bubbles on the surface of the yield, and some NO2 being released (large bubbles). Seemed there was not enough surface movement - and probably mixing happening - and the cold air in the freezer was causing the surface to freeze up (at first it seemed biphasic but that was not the case). After speeding up the stirrer, it seemed to stabilize and the frozen layer dissipated.

The color of the waste and yield phases was much different this time than before and expected. Instead of the vibrant blue and green, there was barely any perceptible color at all. In the end, the yield was a slight yellow-green and the waste layer was ever-so slight light blue, like a very light blue sky. Very unexpected from past experience seeing such vibrant colors and the waste was truly ever-so slightly tinted blue.

While sitting in the separatory funnel for 20 minutes, it released a little brown NO2. The solutions did NOT effervesce bubbles like before - no noticeable gasses erupting into the yield layer at all, which was much different than before. The yield was also a darker yellow/amber than previous batches.

Neutralization occurred with some slight fizzing/bubbles this time, which means that the old baking soda before was not viable. The yield went from a yellow-amber to a light yellow during neutralization.

Raw yield was 112 mL and final yield after neutralization was 96 mL. Currently drying on MS4.

Take-aways:
1. Will change the drop tube to a larger 24mm ID glass tube fitted with a rubber stopper with 5mm hole for the pump tube. The drops should fall nicely into the solution and not slide down the inside of the tube since the diameter of the drop tube is larger
2. Plan to also draw out the drop to 3 hours, maybe slightly more. Should help with keeping the temp. low with less stops needed to recover temp.
3. Will monitor the stir speed better to prevent any frozen layer on the surface and keep the solutions mixing adequately.

Charlie said on Mon, 8 Nov 2021 at 23:38...

The Professor said on Thu, 28 Oct 2021 at 19:05...

If my math is right, n-Butyl nitrite molar mass = 103.12 g/mol
and density = 0.882 g/mL. Molarity should be

molarity (mol/L) = [density(g/ml) X concentration(%) X 10] /
molar mass(g/mol)

[0.882 X 100 X 10] / 103.12 = 8.55 mol/L

1 mole of that should be

X mole C4H9NO2 = X mole / molarity

= 1/8.55 = 117ml

Glad to see raw yield of 112mL is not that far off perfect yield. Seems only about 4% off.

Is there any calculation to determine a perfect yield after neutralization?

The Professor said on Tue, 9 Nov 2021 at 01:12...

Fantastic results!
Going colder changes the game entirely eh?
Very nice yield also.
It's more practical to go by bride yield than after neutralization, because neutralization is going to destroy a certain amount of nitrite, depending on feel time. If person X likes to neutralize for 5 minutes, they'll have less nitrite than someone who neutralizes for 2 minutes.

Measuring crude nitrite will also fluctuate, but not as much. For insurance, if you measure crude yield immediately, the yield will likely still contain some water. If you wait 15 minutes for the water to settle out, you'll get a slightly different (lower) measure of crude.

I've become accustomed to letting a 1 Mike batch settle in a separate tube for 15 minutes, letting water fall into the waste phase, before I measure

The Professor said on Tue, 9 Nov 2021 at 01:14...

Typos:
Bride... Crude
Feel..... Dwell
Insurance.....instance
Mike..... Mole

The Professor said on Tue, 9 Nov 2021 at 01:15...

Typos:
Bride... Crude
Feel..... Dwell
Insurance.....instance
Mike..... Mole

Charlie said on Tue, 9 Nov 2021 at 03:09...

All thanks to you Prof. That's exactly what I did. I let the mix settle for 15 min in the separatory funnel (not the 20 in the guide). I was getting impatient.

Does acid before neutralization make up any measurable volume in the raw yield?

Being anxious to use the nitrite, I tried it for an extended period (an hour). It had an midly acidic scent and over time, it dropped blood pressure (dizziness) and caused blue fingers/toes. Was my mistake not allowing the yield to cure on the sieves or should I neutralize it longer perhaps?

Charlie said on Tue, 9 Nov 2021 at 04:42...

Neither of the first 2 batches had this effect, but I also allowed them to cure for days before using them for any length of time.

Wondering if there was residual acid in the new yield that had not yet been adsorbed by the sieves or sunk by potassium carbonate? The drop in blood pressure was very pronounced and unpleasant - definitely not desirable...

Looking through the list of byproducts wondering if any of these could be the cause?
http://poppersguide.com/forum/11123

The Professor said on Tue, 9 Nov 2021 at 18:06...

Water settles out of the yield more quickly, but some acid will remain dissolved. It depends on the nitrites solubility, and how much excess acid you use. There shouldn't be very much though.

I'm guessing that there still remains some acid in the yield.

I'm going from memory, which is never a good thing for me, but

Side reactions usually include creation of acetates (which will make the yield smell sweeter, and help nastier things happen later on).

Formic acid (has a nasty Aromas and no effects)

Acetic acid ) the first step in forming acetates.

None of that should be able to happen if the Rx happens slowly (and cold).

A third side reaction of prep can be excess acid, which usually produces phlegm, sore throat.

Problems after prep include generation of nitRATes (much higher body load that nitrites, still has effects, but undesired effects are magnified (extremely low BP, long recovery times), and aldehydes (more lethargy no good effects.

I personally wait until my post processing is done, and the things I do to it take about three weeks. This reaction is sensitive and reversible; it might be hard to wait, but I suggest waiting at least 4 days before making an assessment.

If this result is persistent, we'll have to start looking at what may have been different between batch 2 and 3.

Quickly, it seems that batch 3 was even another than batch 2.

IIRC, this is with n-butanol?

If so, that's a medium reactivity level, and since vasodilation is a balancing act between heart rate and blood pressure, there should be just that.... A balance.

That means that in use, you'll likely notice that your heart is beating faster, but it shouldn't feel like it's desperately trying to leap out of your chest. So faster than nominal, but not alarmingly so.

If either of those two things (heart rate or blood pressure) fall out of balance, then it's either a component of the nitrite putting its thumb on the scale (nitRATes are notorious for this) or your body itself is not metabolizing the nitrite quickly enough.

nitRATes are an example here, not guaranteed (and unlikely at -12C).

So, looking ahead, if the BP thing recurs, it's either the process or the reactivity level.

We can tear into your apparatus, and we can try a less reactive alcohol, whichever ends up working

Charlie said on Tue, 9 Nov 2021 at 19:14...

TY Prof.

Yes, correct n-butanol.

The mix definitely never got warmer than -7C.

I didn't notice this with the first two batches, but I also let them rest for at least 4 days and never hit them for as long as I did yesterday. Everything was OK for the first half hour, but then I definitely noticed a lowering of BP.

There's one thing that you mentioned which rings a bell...phelgm (from excess acid). Definitely noticed this. So maybe there is excess acid. The yield definitely smells acidic.

I will reassess the batch after 4 days on molecular-sieves. I'm considering that possibly I did not neutralize long enough.

Charlie said on Tue, 9 Nov 2021 at 19:42...

Prof., did you say before that the molecular sieves will adsorb some acids in addition to water? (I need to look back through my notes when I can get back to them.)

The Professor said on Tue, 9 Nov 2021 at 20:09...

yes, that's right, ms adsorbs more than just water

Charlie said on Thu, 11 Nov 2021 at 04:56...

Hi Prof.,

I have been meaning to ask about your post-prep curing process, though I understand if your method is proprietary of course. I know and understand that this may be something you want to keep close to the vest. I thought I'd just ask :-) I've just been doing the molecular sieves for 4 days then 10% activated alumina and 2% potassium carbonate after day 4 on the last batches. (I know you mentioned back in the "First Batch" thread that the acid sink can also be baking or washing soda.) Should I be doing more or something else?

The Professor said on Thu, 11 Nov 2021 at 17:40...

What you're doing should keep a dry, fresh and potent nitrite stabilized in a bottle. If you are opening and closing that bottle often, you might want to add 10-15% w/v baking or washing soda.

Charlie said on Fri, 12 Nov 2021 at 21:24...

Ty Prof. I'll follow this advice.

Charlie said on Sat, 13 Nov 2021 at 05:58...

Hi Prof.,

I decided to bottle the yield into 30mL bottles after 96 hours on MS4. I added 3g baking soda and 1 tsp. activated alumina to each 30mL bottle.

I observed many tiny bubbles rise to the surface. Does this indicate that the MSs may not be viable or just still too much dissolved acid even if they are viable? I was using 20% MS4. Maybe neutralize longer?

Lastly, does it matter: a layer or AA with baking soda on top, vice versa or mixed together? Ty

Charlie said on Sat, 13 Nov 2021 at 06:53...

Please excuse the typo: "Lastly, does it matter: a layer OF AA with baking soda on top, vice versa or mixed together? Ty"

Nitritespecialist said on Sat, 13 Nov 2021 at 16:43...

@Charlie....caving of the blood pressure is EXACTLY what I forewarned about and I've noticed it almost exclusively with all the nitrites except the amyls. Isopropyl nitrite caves mine in less than ten minutes. Then I have no choice but to stop. The butyls can cave it in ten to 15 minutes. With IPN, I think it's the nature of the beast. With the butyls, I'm not so sure. It could be worsened by impurities.

With the amyls, I rarely have had my blood pressure plunge to where I felt terrible even when hitting it hard. I developed a love/hate relationship with poppers because of this particular side effect.

Nitritespecialist said on Sat, 13 Nov 2021 at 16:46...

@Charlie....I will be surprised if you don't keep experiencing variation in the look of the reaction and its products no matter what you do. BUT please keep us informed. I would love to know what conclusions you've arrived at 6 months from now.

Nitritespecialist said on Sat, 13 Nov 2021 at 16:49...

@Charlie....I once prevented IPN from caving my blood pressure by taking a dose of methylene blue..drank about 1 ml of a 1% solution.

It not only prevents the anemia, but also the low blood pressure. BUT, I decided I would rather whiff amyl and NOT have to take some antidote.

The Professor said on Sat, 13 Nov 2021 at 18:16...

Charlie,
The pore size of activated alumina is not as uniform as those of molecular sieves; I bet it was the sieves that produced tiny bubbles.

It probably matters for how long the bubbles erupted, but I wouldn't worry about it, unless the sieves didn't do that also (they should have)

I don't see a problem with letting the solids mix in the bottle

Charlie said on Sat, 13 Nov 2021 at 18:46...

Thank you Nitrite. I appreciate your experience. I was telling my other half about the methylene blue after that experience. It occurred about 40 minutes into the session with the brand new yield. I'm curious what happens now it has cured a while and now that I have some baking soda in the bottle.

Prof., thank you. I didn't notice any bubbles with the sieves - only after adding the AA and baking soda. After 96 hours on the sieves, I threw the sieves away and replaced them with the AA and baking soda. The sieves seemed heavy as if they were full and water-logged. They appeared different than when they were new. At this point, the tiny, tiny, tiny bubbles erupted. I put the bottles in the fridge right away so I am not sure how long they continued.

The Professor said on Sat, 13 Nov 2021 at 19:33...

Not having any bubbles from the sieves is a bit alarming; have you tested them? A few beads in the palm, sad a couple of drops of water and they should very quickly become too hot to hold.

A weekend season might last 3 hrs with us, and weekday sessions usually about 90 minutes. I've never felt drugged, nauseous, or lethargic...... Any of the Butyl(s) based alkyl nitrites shouldn't do that (the balance I mentioned earlier)

Charlie said on Sat, 13 Nov 2021 at 20:40...

TY Prof. No, I haven't tested the sieves. I now realized I should have and will as soon as possible. I am about to place another order attempt for some quality lab grade sieves that are from a very reputable supplier of lab materials. I had been using the Loudwolf brand out of desperation to get my hands on something.

The Professor said on Sat, 13 Nov 2021 at 21:17...

I mentioned loudwolf earlier as a source for small amounts of pre-activated sieves; i asked them specifically about that, and they responded that their sieves are pre-activated. If they are dead when you test them, then their word doesn't go very far