Sciencemadness Discussion Board

Resue of isopropanol from chlorophyll extraction

HydrogenFluoride - 27-8-2024 at 04:27

I have been extracting chlorophyll from grass lately, and when I finish with the solvent extraction, just end up boiling off the IPA. I am considering setting up a condenser to collect the IPA as it boils off for reuse. Is the IPA contaminated? And if so, what can be done to clean it up?

RU_KLO - 27-8-2024 at 06:18

If you are going to reuse for the same purposes (Chlorophyll extraction) minor contamination should not be a problem.

Destilation is a good method for purifying (unless an Azeotrope exist with other solvent - but in this case theres only one solvent or maybe water).

At atmospheric condition, a binary mixture of 2-propanol (isopropyl alcohol, IPA)–water forms a homogeneous minimum-boiling azeotrope at 87.4–87.7 mass% and 80.3–80.4 °C [1].

So if you start with 99.9% IPA, you could end with 88% IPA - 12% water (water comes from atmosphere humidity / glassware humidity if open system / glassware not dryied by heat)

So if water is not a problem, then there is no problem.

If you need better purfication, just redestilate the destilate.- NOTE; this will not break the azeotrope.

Not asked, but here is some reading material.

Also, if you are boiling/destilling alcohols is better to do it in a wel ventilated area and with a waterbath. DO NOT use open flame directly.

Attachment: alcohol extrantion Chlorophyll.pdf (376kB)
This file has been downloaded 55 times

[Edited on 27-8-2024 by RU_KLO]

HydrogenFluoride - 27-8-2024 at 07:30

Thank you for the added reading material, I did not know that Chlorophyll was being broken down by heating, and that would explain my low yields.