where can i find isopropyl alcohol?

[ferret]

can someone tell me if 98% is available to general public? i talked to a few chemists, one told me i needed a permit, the other said hed only sell me 100mL at a time... they have rubbing alcohol in there but it is about 64%.. ?? thanks

[SicKo]

check out bunnings its a treasure trove :D

[mescalito]

Ring your local Hydro shop they have this new stuff-Ethanol and almond and some other aromatic??

they sell it for those new resin separting baggie thingies??!

[Auxin]

Here in the states they sell 70% everywhere, but they also have 80, 97, 98, and 99% the last three being for diabetics. Try going someplace they dont know you and say you need 98% because your diabetic and you gotta clean your shit and you need allot because your goin across the country, into the outback, or something. I cant imagine why australia would require a permit for any form of isopropanol! Dude was probably trippin'.

OH, if you can still only get 64% or whatever but REALLY need it stronger heres my trick:

Add a bunch of rock salt, stir it around each day for two weeks, most of the water will form a seperate layer of saturated salt water on the bottom, draw off the upper organic layer (caution, salt is somewhat soluble in isopropanol- really), distil the alcohol to get rid of the salt. You'll prolly get around 90% or better.

Awww, I gave away a clue to a secret trick- dont think too hard, I'm still developing the secret trick and I dont want competition.

[ 30. April 2003, 16:28: Message edited by: Auxin ]

[Rev]

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Edited April 21, 2007 by Rev

[Rev]

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Edited April 21, 2007 by Rev

[Fractalhead]

I'm pretty sure i can confirm bunnings has 90+% for sale. Its in the acetone/paint stripper section

According to Vogel's Textbook of Practical Organic Chemistry, it is standard practice to dry any moist solvent over salt before distillation, except for those solvents or liquids that are practically insoluble in water. My understanding is that drying with salt prior to distillation binds the water and minimises the amount of azeotropic water carried over. The constant boiling point fraction of moist isopropanol boils at 80 degrees C and contains ~12% water. To what degree drying with salt reduces this water content i'm not sure. If i was trying to get 90+% isopropanol from 50% stuff, I would probably fractionally distill the 50% stuff, dry over anhydrous calcium oxide, and then re-distill, and store over more anhydrous Calcium oxide. But I think you can just buy it from bunnings anyway.

Oh yeah, and while we are on the topic of drying solvents... Auxin, you might know.. is it possible to satisfactorily activate common epson salts in a household oven? I know calcium oxide requires temperatures of ~800 degrees C to be fully dried. What are the deals with magnesium sulfate and calcium chloride?

It's easy to make calcium chloride by dissolving chalk in concentrated HCl and then evaporating water and leftover HCl.

Appreciate the info

[Auxin]

"if youre going to distill it anyway, then why bother with the salt?"

To avoid fractional distilation because pure isopropanol only boils 17.7 C lower than water and few people here have a distilation setup that could do a reasonable separation in one run, plus azeotropic distilation kicks in if you just try to do fractional and the product will have more water than if you dry it first (no matter how many times you fractionally distil it the water stays there, isopropanol + some water boils LOWER than isopropanol).

"or at least would you add something to soak up water afterwards?"

At the beginning when its 30% or more water thats just not very practical, after you dry it with salt but before you distil it- sure, go for it. Sodium bicarbonate decomposed to anh. sodium carbonate in the oven (275-300 C for 16-6 hrs) would do it. Anh. magnesium sulfate or anh. calcium chloride would bee too messy due to solubility problems and it would just be funny watching someone try to use anh. calcium sulfate, so your right Na2CO3 is a darned good choice if you want to dry it that extra bit.

[Fractalhead]

Sorry, i meant Anh. calcium chloride for drying CH2Cl2 in storage and Anh. MgSO4 for drying CH2Cl2 alkaloidal extracts. I understand CaCl2 is no good for drying solutions of amines in organic solvents because it reacts with amines. Hence, I'm interested in whether it is possible to dry normal epsom salts (MgSO4) in a household oven.

[Torsten]

Originally posted by Fractalhead:

I'm pretty sure i can confirm bunnings has 90+% for sale. Its in the acetone/paint stripper section

U sure?? I have sniffed every bottle on the shelf over the years and have never come across isopropyl alcohol. Brandnames!!

BTW, the bunnings acetone is very iffy. I made soem argemone extract the other day and the stuff ended up being soggy. Not that that is much of a problem, but it indicates that the bunnings acetaone has a fair amount of water in it. Also, and this is much worse, there seems to be another organic in there that does evaporate easily. Can't tell what it is, but I turfed the extract. Will have to see if I can get usual acetone from Diggers directly or might have to order the expensive stuff from Ajax.

It's easy to make calcium chloride by dissolving chalk in concentrated HCl and then evaporating water and leftover HCl.

Or you could buy a 'Closet Camel' refill pack for a few bucks

Magnesium sulphate that has been dried in the oven for many hours at high heat will do the trick.

[Fractalhead]

Thanks for info. Will check isopropanol next time in bunnings. Also, will try to check get acetone checked on GC. sounds dodgey.

[theobromos]

I was once charged more for a bottle of IPA than the normal price by a pharmacist in England because he thought I might drink it. If only I had had a taperecorder handy I might have got him punished by the Pharmaceutical society.

[Auxin]

Fractal, when you posted I was trying my post so I didnt see yours (I knew that would happen someday).

Anyway- yes, you can dry magnesium sulfate and calcium chloride in the oven. Thats my main use for epsom salts.

Hydrated magnesium sulfate will liquify and boil if your not careful (or even if you are), I kinda creep up on drying it- cook it at 165-175 C for several hours (until its a dry solid again), that will make it the monohydrate, then increase the temp to 225 C or better for several hours, that will make it anhydrous. (textbook temps say it goes to monohydrate at 150 C and to anh. at 200 C but that is generally slow and incomplete).

Calcium chloride- I've had trouble getting a strait answer on that for some reason, reports range from 200 C to over 260 C. Basically (if your starting with the dihydrate) cook it at 200 C for several hours (this will at least get it to the monohydrate), then increase oven to max. temp and cook it for several more hours to get it anhydrous.

Oh, and yeah- if your starting with 50% isopropanol starting with fractional and working from there would be best, but when you do the fractional add some salt to make it easier (I've never messed with anything under 70% for good reason- too much damned work).

"I understand CaCl2 is no good for drying solutions of amines in organic solvents because it reacts with amines."

AND ALCOHOLS, never forget that- its soluble in lower alcohols and it also forms the equivalent of hydrates with them (ie. CaCl2.2CH3OH)

[nabraxas]

blimey. i sort ov get what you're all saying, but isn't it wonderful how much complexity- in all ways- there is to even 1 ov the most simple steps in extraction.

& that length ov oven time would kill my electricity bill.

[Remut1]

What laws you got i can get 99% isopropanol of the shelf at the store. I would like to send you some for a seed trade.

diabetics needles, i go to buy a few and they give me some. Must think i do drugs. Oh i do sorry. But never needle i perfur tea.

PM me if you want some. 99% stuff

[planthelper]

99,5% at the pharmacy its expensive thou, 30 aus for 500ml or even more.

[Plantsoma]

Sorry, no isopropynol at Bunnings in Newcastle.

No hardware store has got it or can get it either.

Isocol is the closest thing available at Woolies, but, although it lists no other ingredients, i know it is no way near pure & probably contains antiseptic or something greasy.

If anyone can get this stuff hassle free, pls share the source.

[John_Barleycorn]

Dazd:

If anyone can get this stuff hassle free, pls share the source.

Bigger swimming-pool places supply it. My lot appears to be about 90%, and evaporates to leave quite a bit of solid behind. Otherwise, befriend a panel-beater, as it is used as a thinner for auto paint. I assume that would probably be 100%, as water wouldn't be too desirable. But I must admit that I am hard-pressed to think of any application for which another alcohol wouldn't work.

As for drying salts, I seem to recall looking at the Merck a while back and concluding that Na2SO4 would be an ideal general-purpose drying salt, as it holds a lot of water of crystallisation, dehydrates in the oven readily, has very little solubility in most organic solvents, and isn't a Lewis acid/base. On the other hand, it's not something you can just pick up at the supermarket, and so I suppose there will be some desperados who want to know how to make it. Off the top of my head, a practical route might involve oxidation of a sodium metabisulphite solution (available from brewing supply shops) with something like sodium hypochlorite (from swimming pool places). But I stress that I haven't checked this out, and such redox reactions can generate a lot of heat if performed too fast.

[soma8]

The colloquial name for the soldiers of ANZAC is a little clue I will drop with regard to a perfectly pure source if ipa. It says on the bottle '100%', which I have been lead to believe may just be true. I haven't done an evaporation test on it, but it cleans my monitor well. It's a bit expensive, about $5 for 200ml or something like that. I forgot to ask them whether they sold it in bulk containers. They probably do, everything else they had (toluene, xylene, shellite, etc etc) was available in 20L and 200L quantities as well.

IPA has a reputation from what I have read, for being a good recrystallisation/purification solvent. Probably this is a factor of it's particular polarity.

[Auxin]

You poor guys, over here you can get 99% IPA for about 1 USD per 473 ml and 70% IPA for 0.39 USD per 473 ml (assuming you buy them on sale anyway).

Na₂SO₄ is a well respected, VERY commonly used drying agent in chem labs, insoluble in most organics with the exceptiom of glycerol. As for where to get it OTC I dont know- I recently made two fistfulls magnesium carbonate from baking soda and epsom salts and recovered four fistfulls of hydrated sodium sulfate as the byproduct. If you have good scales and good math (to get the stoichiometry right) you could do the same and just reverse the product/byproduct designations (a little MgCO₃ is good to have around anyway).

[gerbil]

Dazd:

Sorry, no isopropynol at Bunnings in Newcastle.

No hardware store has got it or can get it either.  

Isocol is the closest thing available at Woolies, but, although it lists no other ingredients, i know it is no way near pure & probably contains antiseptic or something greasy.

If anyone can get this stuff hassle free, pls share the source.

Isocol contains about 640ml IPA per litre, somewhere around there.

Last time i checked a chemist for some, one chemist said "no sorry it's illegal to sell", and the one down the road "we can see you 25ml viles for 3$".

[Auxin]

How did IPA get so damned restricted in australia?

If your gov gets any more restrictive about chemicals you'll have to show two forms of id just to buy water (over here you get harassed by the cops if you buy ice, so I shouldnt really be talking I guess).

Just dont tell CNN how opressed you are or the US gov't might try to "liberate" you (I hope you dont have any oil).

Maby y'all should just buy vodka and work from there whenever ethanol can be used instead of IPA. It takes a bit of work to get vodka to 95% ethanol but you gotta do what you gotta do, right?

[Fractalhead]

I can confirm that bunnings in WA, at least, have 'Diggers' 100% Isopropyl Alcohol. NOTE: Always take claims of 100% purity with a pinch of salt. Its not cheap though. 125ml for ~$8.50. Still, it works wonders on those grubby computers etc i suppose

Have been thinking about the acetone impurity, T. I'm assuming that you meant to say that it did NOT evaporate easily, otherwise i don't see how you would have noticed it. My guess is that the impurity is 4-methyl-3-penten-2-one, the aldol condensation product of acetone with itself. I'm not sure how soluble this stuff is in moist acetone, but provided its solubility is low enough, its conceivable that it could be formed 'very' slowly in moist acetone, by aldol condensation of acetone with itself catalysed by H+ and OH- ions present as a result of the autoionisation of water.

Here is an MSDS:

MSDS for 4-methyl-3-penten-2-one

Doesn't sound like the sort of stuff you'd want to be ingesting. Then again, you should see the MSDS for table salt The bp of this stuff is 130 C, so that might help explain any dampness left in the extract residue. According to the MSDS, it has a characteristic smell, so you might be able to do a little test to confirm what's going on. If you get some of the good, clean acetone, and add a little conc. NaOH (aq), let it sit for a few hours, and then evaporate this reaction mixture, some of the good stuff, and some of the original bad stuff, compare the smells and if you notice the same residual smells in the reaction mixture and the original dud acetone, you might conclude that you are on the right track. Of course, one might say, 'why bother when you can just buy the good stuff'.

[Torsten]

Originally posted by Fractalhead:

I can confirm that bunnings in WA, at least, have 'Diggers' 100% Isopropyl Alcohol. NOTE: Always take claims of 100% purity with a pinch of salt. Its not cheap though. 125ml for ~$8.50.

Bunnings doesn't sell many diggers lines in NSW anymore. And I have never seen the IPA. Will have a look though. Does it have any name besides IPA on the label? (so I can look it up on their database)

Have been thinking about the acetone impurity, T. I'm assuming that you meant to say that it did NOT evaporate easily, otherwise i don't see how you would have noticed it.

Well, there was a different smell and yes, once the acetona was gone there was a residue of water and some organic. It seemed to me that organic evaporated before the water though, but that could have been due to azeotropic 'distillation'.

Doesn't sound like the sort of stuff you'd want to be ingesting.

Which is why I mentioned it. Diggers acetone is difficult to get now that Bunnings owns all the Hardwarehouses. So I presume that many people will be using the crap acetone on their precious herbs and might end up wasting them or poisoning themselves. I turfed the batch of argemone I did, but this isn't always a likely option for other people.

Of course, one might say, 'why bother when you can just buy the good stuff'.

Yes, that's what i will be focussing on. I don' like supporting Bunnings anyway. They are owned by wesfarmers and wesfamers happens to be one of australias top 3 hardwood woodchippers. Wesfarmers and Boral have been on my list of companies to avoid at all cost for many years for exactly this reason.

[ferret]

thanks alot everyone- alot of info to digest there for a first year chem student...

ill keep lookin...