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To smoothen 3D printed PLA parts I need ethyl acetate. This is a pretty cheap solvent to synthesize but still to expensive to buy, so I would like to make it myself.

I have seen that ethanol and acetic acid are combined in a Fischer esterification with sulfuric acid as catalyst, then the solution gets distilled afterwards to yield ethyl acetate. I don't have sulfuric acid but I have:

  • Ethanol 95% (with impurities to make it non consumable)
  • Acetic acid 8%

Also, I don't really have to distillate the solution since the other chemicals don't harm the PLA. Will simply mixing these two solutions produce a little bit of ethyl acetate? And how can I maximize the yield?

Mehdi Nellen
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    It's actually kinda funny because I answered a very similar question about an hour ago. I wouldn't use acetic acid, even $\ce{HCl}$ will be significantly better. – andselisk Jun 29 '17 at 12:31
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    In the absence of other acids you can give acetic acid a shot, though make sure to distill the water out with a $\ce{CaCl2}$ drying tube. – andselisk Jun 29 '17 at 12:34
  • And why don't you just use acetone for finishing your parts? It's dirt cheap and readily available. – andselisk Jun 29 '17 at 12:38
  • Acetone works on ABS, I have some CaO will that also work to get water out? – Mehdi Nellen Jun 29 '17 at 12:40
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    My bad, I didn't know that. You can use calcium oxide, but keep in mind that it reacts with water exothermically, and don't let the forming $\ce{Ca(OH)2}$ contact with your mixture. – andselisk Jun 29 '17 at 12:47
  • so I have to minimize the amount of water in the staring acetic acid solution before mixing it with ethanol (and maybe HCL)? And need to slowly do the CaO mixing because its an exothermal reaction? – Mehdi Nellen Jun 29 '17 at 12:53
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    Pretty much, unless somebody else suggests a different approach. – andselisk Jun 29 '17 at 12:55
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    My suggestion is to never attempt to make a commodity solvent when you can buy it. It's a waste if time and money. You'll also need to purify it... – Zhe Jun 29 '17 at 14:19
  • @Zhe understandable suggestion, but as a hobby its a nice project, also for experience/learning – Mehdi Nellen Jun 29 '17 at 14:58
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    You'd need glacial acetic acid, there's no sense in starting from diluted. Also catalyst is a must have. – Mithoron Jun 29 '17 at 15:16
  • If you are willing to do this purchasing it, then you will rapidly notice the close boiling points of ethanol ($\pu{78 ^\circ{}C}$), freely water soluble and able to solute the product ethyl acetate ($\pu{77 ^\circ{}C}$, equally English wikipedia). Of course, for the pure compounds. I wonder why solid state acids like some zeolithe and acidic ion exchange resins like Amberlyst 15 were not yet mentioned here. The methyl ester prepared at room temperature in www.arkat-usa.org/get-file/44731/ is interesting, yet isolation and purification there is much easier than here (reactive distillation?). – Buttonwood Jun 30 '17 at 00:15

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