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tsathoggua1
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Yowch. That price on the aniline stinks as bad as the product.
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A Halogenated Substance
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Location: United States
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Mood: Oxidizing due to extended exposure to oxygen
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Sodium thiosulfate for work with halogens, potassium chromate for organic synthesis, and 95% ethanol for stabilizing chloroform and organic synthesis.
Current Active works in Progress:
-Convert i-propanol to i-chloropropane using HCl and ZnCl2
-Determine properties and solubility of a glycerol and citric acid polymer
-Attempt a conversion of chloroform to dichloromethane
-Attempt a conversion of acetic acid to acetamide
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mayko
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Found a big ol' bucket of calcium hypochlorite on the side of the road... mass production of chloroform is on the horizon
al-khemie is not a terrorist organization
"Chemicals, chemicals... I need chemicals!" - George Hayduke
"Wubbalubba dub-dub!" - Rick Sanchez
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Db33
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Didnt plan on these 2 arriving on the same day but it happend that way.
1,2, Dichloroethane
Dichloromethane
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Db33
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this might be a little off topic but does everyone see the dichloromethane can? im having a hell of a time opening the lid, you have to push down and
then open but it is not working, its like on alot of paint cans, any advice or tips on how to open it?
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JJay
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Channel locks... or just remove the childproof cap with a utility knife.
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Db33
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ive removed the childproof cap before on a can of Toluene just to get to a metal lid that was even harder to open haha. So i dunno, channel locks i
think i might give a shot
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Sulaiman
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Potassium bromate 75 g. 99%
I want bromine but I'm too lazy to do the electrolysis 
0.01 £/g 
0.10 £/g including p&p from Russian Federation 
CAUTION : Hobby Chemist, not Professional or even Amateur
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JJay
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Lately I've been purchasing mainly fairly common but essential chemicals in bulk. Stuff like:
calcium hypochlorite
calcium hydroxide
sodium sulfate, anhydrous
potassium carbonate
I've been thinking I should probably get some oxalic acid.
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woelen
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Sodium peroxide, 800 grams.
I intend to use it mainly as peroxide stock. Concentrated H2O2 cannot be purchased anymore where I live, it even is hard to find more than 3%
solution. Na2O2 has the advantage that it has a fairly high peroxide content, but the best thing is that it can be stored indefinitely if kept in a
tightly sealed container, unlike H2O2 which decomposes in a few years.
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Sulaiman
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there's still oxy-clean (sodium percarbonate) as a source of H2O2
CAUTION : Hobby Chemist, not Professional or even Amateur
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woelen
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I know of sodium percarbonate, but its peroxide content is quite low. Anhydrous Na2O2 has a fairly high peroxide content in terms of weight and still
can be purchased (I have it from eBay). Converting it to moderately concentrated H2O2 (e.g. 15% or maybe even 20%), is not really trivial, but is
doable.
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j_sum1
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Quote: Originally posted by woelen  | | I know of sodium percarbonate, but its peroxide content is quite low. Anhydrous Na2O2 has a fairly high peroxide content in terms of weight and still
can be purchased (I have it from eBay). Converting it to moderately concentrated H2O2 (e.g. 15% or maybe even 20%), is not really trivial, but is
doable. |
I had a quick search and found lots of discussion but little concrete. If you don't mind, how does one go about getting H2O2
beginning with Na2O2 or Na2CO3·1.5H2O2?
[edit]
I searched on the percarbonate and found three dead-end threads with lots of fluffy contradictory talk but nothing very helpful. I did less searching
on sodium peroxide. I know that Na2O2 reacts with water to form NaOH and H2O2 but I am not sure how you would separate the two.
[Edited on 4-4-2017 by j_sum1]
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woelen
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Getting H2O2 out of Na2O2 and isolating that to high purity is not easy, but making a fairly concentrated solution, which also has some left-over ions
in it is not that difficult.
Na2O2, when added to water, reacts to give NaOH and H2O2. This reaction is quite exothermic and the heat, produced in this reaction is comparable to
the heat, produced by dissolving NaOH in water. You can make the liquid quite hot if you add a lot of Na2O2 to a little water quickly and probably a
large amount of the formed H2O2 then will decompose.
So, you have to add the Na2O2 to ice cold water. If the water becomes too warm, then cool inbetween and add the Na2O2 in different small batches. I
would take 100 grams of Na2O2 and add that to 100 ml of water, assuring that the liquid does not heat up too much. This may take quite some time!
Next, add 30% H2SO4 or so, also slowly, in different batches to neutralize the NaOH without excessive heating up of the liquid. Add acid, so that the
liquid becomes neatral (a little excess of acid is better than too little of it). Na2SO4.10H2O is not freely soluble. I expect quite a lot of
crystalline solid to separate, leaving a solution of H2O2 in water. The solid also takes out water. I am not sure about getting H2O2 in the crystal
lattice.
This method is not something I tried, but I expect, however, that it is a viable method of making moderately concentrated solutions of H2O2. When the
Na2O2 arrives, I'll try it with a small amount, to see how well this works. The solution will still contain some Na(+) ions and SO4(2-) ions. In most
applications, this is not an issue.
With sodium percarbonate things should work similarly, but the solutions will be more dilute and you have a lot of bubbling of CO2. The reaction of
sodium percarbonate with water is less exothermic than the reaction of sodium peroxide with water.
------------------------------------------------------------------------------
 For the more greedy ones: almost 100% H2O2
Add solid Na2O2 to 98% H2SO4 and get the following reaction: H2SO4 + Na2O2 --> Na2SO4 + H2O2. You get crystals of Na2SO4 in almost 100% pure H2O2,
just decant the pure H2O2
There is one caveat though: This is the ultimate april fool's joke 
Do not do this in real life! The extremely basic Na2O2 will react very exothermically with the strong acid and you may have lots of H2SO4 splattering
around and the H2O2 immediately decomposes to water and oxygen. I will try this experiment. I take a small spatula of solid Na2O2 and add a single
drop of concentrated H2O2. Let's see what spectacular thing happens!
--------------------------------------------------------------------------------
Now that I am writing this, it makes me angry again about all these regulations in the EU  . The above process is a lot of hassle just for getting some H2O2 in reasonable concentrations, but we have to deal with it. Buying a
liter of 35% H2O2 at a local drugstore as I did 10 years ago definitely is something from the past! The same drugstore now only has 3% H2O2 in 100 ml
bottles and they only sell it from a locked room, not freely available anymore in the shop.
[Edited on 5-4-17 by woelen]
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Gurt
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As far as chemical orders, I have had a rather good week.
5L lab grade benzene
1L Isopropylamine
1L Carbon tetrachloride
100g Malononitrile
250g Sodium
5g Juglone
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Sulaiman
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Potassium Bromate arrived
Strange world
... a packet of white powder posted to me in UK from the Russian Federation arrives in a week, no signs of physical inspection,
yet stuff from US is strictly scrutinised (for tax purposes I think)
(i.e. my government seems more interrested in taxing me than protecting me, and others)
Anyway, £7.50, one week delivery, 85g (labeled, not a mistake) instead of the advertised 75g, KBrO3 with assay.
Quick & easy Br2 production soon ..... (I need to practice diy ampouling first)
CAUTION : Hobby Chemist, not Professional or even Amateur
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tsathoggua1
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1KG of anhydrous KOH.
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JJay
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Anhydrous KOH? An entire kilogram of it? That stuff is expensive.
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clearly_not_atara
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| Quote: Originally posted by Db33 | | this might be a little off topic but does everyone see the dichloromethane can? im having a hell of a time opening the lid, you have to push down and
then open but it is not working, its like on alot of paint cans, any advice or tips on how to open it? |
If I'm having trouble with a lid like this, I usually put my palm flat on the top of the lid and press down very hard while twisting my hand so the
lid turns via friction.
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tsathoggua1
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Was cheap enough, wanted it for eutectic mixtures of NaOH/KOH, apparently the mixture melts at just 200 degrees, well below the point at which Na
dissolves into NaOH to make that interstitial type blue-grey rock hard crap.
Not a friendly melt to the nickel anodes I've been using. I'm hoping carbon electrodes will survive longer and allow taking advantage of the great
conductivity of carbon.
Currently-5l GAA, 10l CH2Cl2, 5g HgCl2 and a couple of other chemicals, as well as a 150ml glass syringe, a nickel crucible, 2 nickel plated ones, 2
Fe ones, and a set of carbon crucibles ranging from about an inch and a half tall and 3/4-1'' ID to 6-7 inch tall and about 4.5-4.75'' ID. The larger
one is graphitic, whilst the others are amorphous carbon. I'd like some glassy carbon crucibles but those don't come cheap. Finding something that
will resist molten KOH/NaOH mixture is fairly demanding of course on the materials used.
Need a new power supply too, although I've just spent a large proportion of my budget for that kind of thing.
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JJay
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I just did some searching for anhydrous KOH and ran across this: https://www.amazon.com/PURE-Potassium-Hydroxide-Flakes-Anhyd...
The label is misleading, though; it's not actually anhydrous. Real anhydrous KOH is made by reacting sodium hydroxide and potassium in a molten state.
I'm not really sure how they separate the KOH and sodium afterwards... perhaps zone fractionation would work, or for all I know they simply distill
off the excess alkali metal (don't try that in borosilicate glass). Sigma-Aldrich does carry anhydrous potassium hydroxide, and I believe that theirs
is genuine, but it's very expensive.
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tsathoggua1
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Whai about grinding fresh-fiused KOH? obviously, in a dry atmosphere. Stuff is damnably hygeoscopic.
Or better, vacuum dessication, should that not pull any water present out? although this product isn't commercially brand-packaged, but rather was
sent in a hermetically sealed bag.
Although mostly atm traces of water don't matter considering the primary use is in molten hydroxide eutectics and at a minimum temperature of 200 'C.
probably not the most optimum conditions for retaining water.
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JJay
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KOH can't be dehydrated that easily; in "anhydrous" commercial form, it generally contains between 10-15% water.
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JJay
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I try to recycle my DCM whenever possible, but I was running low. Also, I saw acetone on sale.
![IMG_20170419_222716[1].jpg - 654kB](https://www.sciencemadness.org/whisper/files.php?pid=481079&aid=58716)
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tsathoggua1
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if only such were OTC here. Just bought 20 liters of dichlor, 5l ethylene glycol for chlorination to 1,2-dichloroethane (even here they do trust
people to mix their own antifreeze with water), some ACS grade benzaldehyde (god I love that smell. Made use of the benz twice, involving some
microwave chem....and damned if that smell doesn't get out given the tiniest chance. Had a house that smelled like cherry bakewell tarts/marzipan for
days.) Always found the smell of benzaldehyde, of nitrobenzene, nitromethane/ethane good enough almost to eat. Might even get used as a flavouring for
cooking, since its harmless enough in the amounts used to make commercial artificial almond flavouring.
Also, some HgCl2, 5g which will most certainly not. Some very, very fine nickel powder, around 250g, 250 or 500 each of nickel acetate and
dichromate. The nickel salts are planned for playing around with Ni-Cu couples as reductors. The dichromate intended for the etard, via the rather
useful CrO2Cl2, which most surprisingly, will oxidize an alcohol to an aldehyde and stay there, odd really, considering that its incompatible with
most solvents bar chlorocarbons, perfluorinated alkanes (I think) and CS2. I've worked with it before and had an accident once many many years ago
whilst still learning (well we are always still learning. I meant rather, starting out as a hobby chemist) and I've seen what it likes to do to
organics and it isn't pretty. That its so gentle on alcohols still never fails to surprise.
As far as drying KOH goes, surely flame fusion and maintaining it in the molten state, preferably in a bag or chamber with dessicant present should
expel the last of the H2O? Another option is a molten metal bath I have, that will reach up to 500 degrees. I can't see it taking on much water whilst
maintained at a melt temperature (this is more likely 200 'C, or close to it, a little above, since primary motivation atm is production of NaK alloy.
Have succeeded in its transient production but not as of yet captured any. Using a NaOH-KOH eutectic, and going to move to carbon electrodes, was
using nickel alloy fret wire for the anodes and carbon crucibles, will stay with the crucibles as they resist attack when serving as cathodes whilst
the anode, when nickel wire was used ended up quite badly attacked at the tips, forming an extremely sharp point. Would be an ideal way for making
beehive type flechette rounds for shotguns come to think of it, mass dip say half inch long fret wire pieces wired as anodes in KOH-NaOH melt, reverse
when sharp and instant finned sharpened projectiles if somebody wanted such.
[Edited on 23-4-2017 by tsathoggua1]
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