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Author Topic: Is bio-ethanol a valid substitute for tech-grade ethanol?  (Read 3759 times)

Offline valeg96

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Can bio-ethanol -the transparent one sold sold at hardware stores- used for simple experiments in place of technical grade 96% ethanol? I wouldn't mind buying it from my chem supplier or in a supermarket, but the Italian govt imposes a heavy tax on food grade/edible ethanol (1 liter costs 3 for the alcohol + 15 for the state monopoly, so for 18=20$ I can get much more stuff). How about the denaturated one? It's bright pink, and I profoundly doubt it can be of any use.

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The European Union agreed in February 2013 to the mutual procedures for the complete denaturing of alcohol:
    Per hectolitre (100 L) of absolute ethanol: 3 litres of isopropyl alcohol (IPA), 3 litres of methyl ethyl ketone (MEK) and 1 gram denatonium benzoate.
  http://en.wikipedia.org/wiki/Denatured_alcohol [nofollow]


 

Offline Bored chemist

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #1 on: 01/04/2014 19:06:45 »
It depends what you are trying to do, but generally, no.
The impurities in the denatured alcohol will stop a lot of experiments working properly.
 

Offline valeg96

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #2 on: 01/04/2014 20:26:27 »
So It's negative both for denaturated and bio-ethanol? That's a shame, it was relatively cheap...
 

Offline CliffordK

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #3 on: 01/04/2014 21:20:27 »
What if you built a reflux distillation column?

Hmmm, any dye, and the denatonium benzoate should be pretty easy to knock out.  The isopropanol may or may not affect your experiments.  The MEK might be a problem depending on your needs as its BP is pretty close to the ethanol.  You could probably find something to react with the MEK, then distill, but you quickly end up spending a lot of time, effort, and money in your distillation.

What about using just isopropanol instead of ethanol?  You should be able to find 98% or 99% isopropanol pretty easily (at least in the USA).

What is the "bioethanol" in Europe?  Here in the USA they sell E85 which is about 85% ethanol, and 15% gasoline.  I've used it as a general solvent, but not for chemistry experiments.  Gasoline is generally not a pure substance, so it might be a pain to distill out of the ethanol, but if you were careful, you might be able to get most of it out, especially if you were liberal with wasting the early and late distillates (which can go into your car).

Hopefully you're not making stuff that you are intending to eat.
« Last Edit: 01/04/2014 21:25:24 by CliffordK »
 

Offline valeg96

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #4 on: 02/04/2014 09:44:12 »
The isporopanol is either sold pure for about 7/L -very rare to find- or fruit/flower parfumed for 1-2/L, only sold in huge DIY retail stores, and I don't trust parfumed products at all, I don't need more variables that can make my activities fail.

I found two MSDS, one says it's pure ethanol (CONTAINS: Ethanol), the other says there's 96% ethanol, 1% MEK, 0.008% denatonium benzoate.
 

Offline CliffordK

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #5 on: 02/04/2014 15:35:40 »
You may also talk to auto racing suppliers about race fuel, either methanol or ethanol.
 

Offline Bored chemist

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #6 on: 02/04/2014 16:51:27 »
Distillation is almost certainly illegal.
 

Offline valeg96

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #7 on: 02/04/2014 20:30:42 »
Before legality, I'd think about safety. And honestly, distillating a solution of >98% alcohols doesn't seem safe at all. I'll check the composition of bio-ethanol and evaluate if it can be of some use. Thank you all!
 

Online chiralSPO

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #8 on: 03/04/2014 16:43:48 »
The guy with a bucket full of lead oxide thinks distilling alcohol is not safe?

As long as the still has a pressure release mechanism to prevent explosions, is filled with an inert gas (or evacuated) and heated with a non-open flame non-sparking heater, distillation of most solvents is pretty safe. If you're nervous, a blast shield never hurts. (And of course you usually don't want to distil more than 90% of the initial material, especially with peroxide-forming compounds)
 

Offline valeg96

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #9 on: 03/04/2014 18:06:42 »
Yep :3 I'll do it once I'll have gathered better equipment and maybe in my friend's lab in pair with the supervision of a chemist. Assuming now it's be safe, let us not forget that

Distillation is almost certainly illegal.

Just cheked, It's illegal unless you pay some permits/taxes. I guess I'll be giving money to the ol' fellas in Rome anyway, I'll look it up at a bigger chem retailer.
« Last Edit: 03/04/2014 18:08:13 by valeg96 »
 

Offline CliffordK

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #10 on: 03/04/2014 20:34:53 »
You really need to get your lab connected to a business or educational facility. 

Here in the USA, there are chemical suppliers such as Sigma-Aldrich, that will sell just about everything, but I'm not sure if they ship to individuals.  It looks like there is also an Italian branch.  They do sell lab grade solvents, but I don't know how taxes affect the prices. 

It is likely that isopropanol or methanol will substitute for many uses of ethanol. at least as a solvent, not necessarily as a reactant.
 

Offline SorryDnoodle

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #11 on: 04/04/2014 07:05:54 »
You really need to get your lab connected to a business or educational facility. 

Here in the USA, there are chemical suppliers such as Sigma-Aldrich, that will sell just about everything, but I'm not sure if they ship to individuals.  It looks like there is also an Italian branch.  They do sell lab grade solvents, but I don't know how taxes affect the prices. 

It is likely that isopropanol or methanol will substitute for many uses of ethanol. at least as a solvent, not necessarily as a reactant.

Sigma-Aldrich is really, really expensive though, it kind of depends on where you live but for example:

Ethanol
200 proof, anhydrous, ≥99.5%  105 dollars for 1 liter in the US

Same thing costs 160 dollars to sweden, not including the shipping costs either.

Perhaps it is the hazard fee, I do not know. But 1 single liter costing this much is very expensive either way.


By the way, what are you going to do with the ethanol?
 

Offline valeg96

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #12 on: 04/04/2014 14:45:42 »
In Italy reagents are usually sold by Carlo Erba Reagents, or by smaller industries. I can ask a chemist the price/to order some as a school/educational facility, but bureaucracy (checking the supplier, asking the ministry for refund, getting permissions, confirming the purchase, ask for payment, actuate payment, shipping) drags the whole process for months (my school ordered some reagents in Sept 2013 and they'll arrive -we hope- in June 2014).

And nope, all reagent industries/manufacturers sell&ship only in bulk, both reagents and glassware. The only way is to find a secondary seller, big enough to have low prices and small enough to sell individual items.

I've asked for some purchases a company re-selling plastic/glass labware and containers that declared on their site "we are available even for small orders" only to find out that a "small" order is no less than 50-100pcs. That would be like 30 in plastic lab bottles, but where am I going to store them all? They'd probably last like 5 generations...

About reagent companies, they all ask for your profession, company name, role and so on. Even to request catalogs or free posters you must insert your company name... I obviously can't lie inserting my CF (fiscal code) saying I'm a teacher or a private who owns an analysis lab.

At the moment I'm using ethanol to prepare vegetal extracts as pH indicators, but it is always useful. How about I keep the 500mL I have (96%, food grade) in its bottle and I use bio-ethanol as solvent?

Are there other good solvents for extracts? Like acetone, cheap and (quite) safe?
 

Online chiralSPO

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #13 on: 04/04/2014 15:14:35 »
Isopropanol, methanol, acetone, butanone (methyl ethyl ketone) and ethyl acetate are all available in fairly high purity as solvents from a hardware store (at least in the US), and are fairly innocuous. They may not necessarily be reagent grade, but should suffice as extracting agents.
 

Offline valeg96

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #14 on: 04/04/2014 17:33:53 »
Uhm, I'll look for the prices of methanol and ethyl acetate. I already have acetone, but it evaporates too quickly.
« Last Edit: 04/04/2014 19:18:51 by valeg96 »
 

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Re: Is bio-ethanol a valid substitute for tech-grade ethanol?
« Reply #14 on: 04/04/2014 17:33:53 »

 

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