# Is isobutanol miscible with ethanol?

I can only find info on sec-butanol (aka butan-2-ol) and ethanol. I need to know whether isobutanol forms an azeotrope with ethanol. Can you direct me to a legitimate info source too, please?

• sciencedirect.com/science/article/pii/037838129180013L Jul 7 '16 at 11:44
• From PubChem, 2 butanol is soluble in water, very soluble in acetone and miscible in ethanol and ethyl ether. If acetone is not a problem you can dissolve in a little acetone then add to ethanol. Jul 7 '16 at 17:13
• Unlikely. Compounds with similar polarity/chemical structure do not form aceotropes with each other. en.wikipedia.org/wiki/Azeotrope#Mechanism
– Karl
Jul 8 '16 at 10:09
• I've come to the conclusion the EtOH and iBuOH are miscible and will therefore not form an azeotrope based on the info provided here and elsewhere. Jul 20 '16 at 21:06
• That's a non sequitur. Compounds may be miscible and still form an azeotrope, like water and ethanol do. Mar 1 '17 at 6:30

According to the Merck Index${^{[1]}}$