Greetings fellow nerds.
This week there is very little sodium work, as i'm waiting for more chemicals to arrive in the mail.
I also landed a new job.
So things have been hectic as i settle in so my videos are going to come out less often but once i have a good routine going i should be returning to normal video production.
Now in other channel news i have received another community guidelines strike on my channel.
This time against my synthesis of sodium cyanide video.
And to be honest, this is the first strike i actually accept.
Now i personally think the educational value outweighs the danger.
But i can see it from their point of view why they wouldn't like it and removing it isn't contradictory to the policies of youtube.
Nor is the reason excessively broad like when they took down my synthesis of the antimalarial drug pyrimethamine.
So i'm not going to fight this particular strike.
I suppose after indiscriminately taking down so many videos, they had to find a valid one eventually.
But since my channel is closer to being banned, i do hope i last long enough to produce my last great project, the sodium synthesis.
Now i as said before i'm still working hard on it and progress has been steady.
In particular i'm trying to get more catalysts for my sodium experiments.
Buying them through the mail is one option, but as i wait i wanted to try making some.
Now one catalyst candidate that's been suggested to me a lot is something called terpin hydrate.
It's based off of 4-terpineol and is actually the product of hydrating the double bond.
The original alcohol group undergoes a migration by passing through an alkene intermediate.
What we essentially get is two tertiary alcohols on one molecule.
Now i'm not sure if this would do us any good, and it might make the resulting alkoxide too polar to be soluble but we might as well give it a shot.
Now i looked for literature on how to make it and it seemed simple enough,
mix a source of terpinenes like tea tree oil or turpentine with dilute sulfuric acid and stir for a prolonged period.
So i did that, i mixed about 200mL of tea tree oil with 200mL of water and added 30g of sulfuric acid and then stirred.
The literature says this should yield a precipitate of terpin hydrate overnight.
Then i stirred for about three days and at the end of it, nothing happened.
I then left the mixture in the back of my fume hood for three weeks and finally a tiny clouding of stuff seems to be coming out.
It's not very much though.
I'm not even sure if we could recover that.
Now some literature sources suggest high concentrations of acid so i tried again with 50mL of tea tree oil, 20mL of water, and 50g of sulfuric acid.
Looks like we're getting some reaction.
But even after a few days I wasn't seeing anything solid.
At this point i kinda abandoned this line of inquiry.
Not because it can't work, i'm sure i'm probably doing something wrong.
But i think my efforts are best spent on more promising avenues like finding an off-the-shelf catalyst.
I may yet revisit terpin hydrate as a catalyst if everything else doesn't pan out.
I'm still leaving this flask in the back of the fume hood in the hopes the reaction continues.
Anyway, as found in a previous lab notes video.
4-terpineol from tea tree oil was found to be a workable catalyst, but decomposes with time so a large starting amount is necessary.
4-terpineol also needs to be isolated from tea tree oil by fractional distillation, which is not all that easy at the temperatures required.
Now a way to solve both problems is to hydrogenate tea tree oil.
This is already well-known chemistry.
Basically add hydrogen to the double bond and hopefully make the resulting alcohol resistant to decomposition.
This would also make all olefinic impurities aliphatic which should be as inert as the mineral oil we're using to run our reactions.
Unfortunately this does not happen by itself.
If you feed hydrogen into an alkene, nothing happens.
So we need a catalyst.
The most common catalyst in the laboratory is palladium on carbon.
If you want actually see palladium on carbon being used for hydrogenation then i recommend checking out Applied Science and NileRed,
both of those channels perform hydrogenation of vegetable oil to make margarine.
They're excellent videos and i've linked them in the video description.
Now palladium on carbon is within the abilities of the amateur to make but like making tertiary alcohols,
it's a rather involved process and you also need to buy palladium.
The effectiveness makes it cheap since you can use very little, but the initial cost might be prohibitive.
So to make my hydrogenations more amateur friendly, i decided to try and make another catalyst called urushibara nickel.
It's not as effective as palladium, but the required chemicals aren't too hard to get.
First i had to make nickel chloride.
Nickel chloride can be purchased online but nickel metal itself is often easier to get.
You can even hack it out of nickel metal hydride batteries and it will work.
So to convert nickel metal to nickel chloride i added it to hydrochloric acid.
But nickel reacts very slowly at room temperature so to speed it up it needs to be boiled.
Eventually this forms nickel chloride.
I made a lot of it since i wanted to do other experiments with nickel and I don't have nickel chloride as a stock reagent.
I then boiled it dry and eventually obtained nickel chloride.
Now making urushibara nickel precursor isn't that hard.
Zinc powder is obtained and a one tenth mass equivalent of nickel metal is weighed out in the form of a nickel salt.
Like our nickel chloride from earlier.
We then add water to both and heat them up until they boil.
From what i read in the literature the more vigorous the reaction the better the resulting catalyst, and thus why we're boiling everything.
Now looking back at this point i think i screwed up.
If you look over at the zinc it seems be rather pasty.
I don't think that's zinc, i think it's more zinc oxide.
The zinc powder i was using must have oxidized over the years over to zinc oxide.
What i should have done before i started was wash the zinc with dilute sulfuric acid.
Zinc oxide easily dissolves in sulfuric acid but zinc metal actually dissolves very slowly because it has high hydrogen overpotential.
Unfortunately i didn't think of that in time, so i went on to the next step.
Mixing the boiling nickel chloride solution directly into the boiling zinc paste.
Now this extremely vigorous reaction is actually perfectly normal.
We're getting a very exothermic metal displacement reaction with the nickel depositing very fine particles onto the zinc.
It's so exothermic that it's boiling the mixture further.
So my crappy zinc still has enough good zinc in it to make this reaction work.
Although i still think i would have been better off using good zinc.
Anyway looking back i should also have used a bigger flask to contain the reaction.
Luckily I had the foresight to install a splash arrestor on the flask before i started to deal with exactly this sort of occurrence.
As you can see i definitely got my money's worth here.
Anyway, I let the reaction continue until it stops.
Next we filter our mixture to get our precursor.
Be sure it wash it with lots of water and finally with some methanol to get rid of all the leftover salts.
And here it is after drying.
Yeah i really think i have way too much zinc oxide.
Hopefully i get some activity out of this but if i don't, i know what to fix.
Anyway, this is the Urushibara nickel precursor.
Basically it's ultrafine nickel deposited on zinc particles.
In this form it's stable indefinitely but not directly useable.
To make it useable for hydrogenation it's reacted with a strong base or weak acid to destroy the remaining zinc and release the nickel particles.
Then those particles are filtered and used for hydrogenation.
But that's best done just before you actually do perform your hydrogenation.
The activated nickel loses activity as it's exposed to air, so it's best kept in this precursor state when you're not using it.
Anyway i'm still preparing for the hydrogenation so i'll get to that eventually.
But as you can see, overall, the process for making the catalyst doesn't seem to be that hard.
If this works as is i'll make a proper video with masses and variables, and if not i'll try again.
Now i've been running a concurrent sodium experiment where i ran with an excess stoichiometric ratio of sodium hydroxide to magnesium.
If you recall i already ran this test awhile back to see if we could avoid using dioxane by making sodium without magnesium contamination.
We found that it was very difficult to finish since the reaction just kept getting slower and slower and even after three days it never finished.
While i decided to revisit that experiment since i had more time now and this time I used huge amounts of sodium hydroxide, almost twice as much and i ran for several days.
Finally the reaction flipped over and all the magnesium was consumed but something interesting happened, the sodium broke up into a very fine dispersion.
You can see it here almost like sand.
Let me see if I can get closer and get a macro shot, and there we go.
It's clearly a spherical metal so it's not the original magnesium just worn down.
When i poured it out most of the slurry passed through the sieve and whatever did collect was very little.
So it seems like a little bit of magnesium is needed to keep the sodium metal together in large globules.
I actually noticed this effect very early in my experimentation but i wasn't certain it was due to excess sodium hydroxide as i was also dealing with glassware destruction at the time.
So I had to consider the possibility it was a glassware contamination problem.
But now it looks like it really is an effect of using excess sodium and letting the magnesium be consumed.
Now you might be wondering how does magnesium prevent the sodium from breaking up.
What i think is happening is the magnesium is imparting a negative charge to the sodium as the magnesium is oxidized by the reaction conditions.
This charge alters the surface tension of the sodium and either allows the sodium to easily coalesce with other droplets of sodium or makes it harder for the sodium to detach and break up.
Perhapes both effects are at work.
We've actually seen a very similar effect way back in the gallium beating heart experiments.
In those experiments the gallium metal changes its surface chemistry in a sulfuric acid solution whenever it's left on its own or when when it touches an iron wire.
In this case we have sodium metal for gallium metal, and magnesium metal for iron.
Bottom line, in order for us to get great sodium coalescence under these reaction conditions we need a small amount of magnesium to maintain the right surface charge on the sodium.
So it looks like we'll always need to run with excess magnesium.
First, because the reaction becomes terribly slow if we don't.
And second, and perhaps the more important reason, because the magnesium maintains sodium cohesion.
You might be thinking that we can use dioxane to recover the sodium droplets from this slurry.
While that might be possible it only underscores the continued need for dioxane.
If we're going to keep using dioxane then we might as well keep with our current methods of using dioxane to separate sodium from magnesium metal.
You know, looking back, i remember lots of amateurs running with excess sodium or potassium hydroxides
when they were doing their experiments since magnesium was the more expensive reagent.
Perhapes a lot of their reaction failures weren't failures at all, but simply loss of product because it was this fine dispersion.
They did report that the resulting slurry was exceptionally reactive, but couldn't collect any large pieces of sodium or potassium metal.
Now that we know product cohesion is dependent on excess magnesium this might offer an explanation.
So you amateurs that were working on this research years ago and kept failing but got highly reactive slurries.
Perhaps you did succeed and didn't know it.
So that's what i've been up to for now as i wait for more chemicals to arrive.
Hopefully they'll get here soon and i can start testing, but if not i'll get to work on hydrogenation of tea tree oil.
Thanks for watching.
At this point i'd like to thank my patreon supporters.
I would never have bothered to research anything this thoroughly or produce lab notes without your approval.
It's because of you that we have come this far, thanks
For more infomation >> Nướng Mực Siêu Cay - Duration: 13:04. 
For more infomation >> Bán acc Làng Lá Phiêu Lưu Ký với giá cực đẹp | Bảo Như TV - Duration: 7:48. 
For more infomation >> MatiK - Psy chodzące w maskach klaunów (Prod. Tower B./L.E.M. Beats) - Duration: 3:09. 
For more infomation >> КТО ТЫ ПО ЗНАКУ ЗОДИАКА НА ХЭЛЛОУИН. Грим на Хэллоуин 2018. Самый Страшный Хэллоуин Макияж в Мире 😱 - Duration: 16:45. 
For more infomation >> Kính hiển vi Olympia M640 (X1.600 lần) - ĐT: 0934189486 hoặc www.thietbimaikhoi.com - Duration: 1:30. 
For more infomation >> Видео поздравление 100 лет ВЛКСМ - Duration: 4:47. 
For more infomation >> 74 samponi protiv buha na psu brzo i ucinkovito rjesenja protiv buha na psu - Duration: 1:42. 
Không có nhận xét nào:
Đăng nhận xét