Sciencemadness Discussion Board

Strange white powder while making Phthalic Acid

Housane - 30-3-2021 at 10:53

I've just tried to replicate Nile reds Phthalic acid video at 1/2 scale and when pouring in the NaOH I got 2 layers instantly and then after reflux I get an orange layer and some powdery white solid, any idea what may have happened?

Syn the Sizer - 30-3-2021 at 11:25

My guess is there was some impurities in the solution. Possibly still polymer which is probably the orange colour. The powder could also be cause by that as well.
Do you know what alcohol was estered with the phthalic acid as the plasticizer?
To be honest, it is fairly cheap to buy phthalic anhydride pure. Are you just doing this for fun or are you having a hard time sourcing it?

DraconicAcid - 30-3-2021 at 11:49

Would the orange layer be the alcohol that you're hydrolyzing off the phthalate ester?

Housane - 30-3-2021 at 13:00

Alcohol was isopropanol and I didn't have a soxhlet so it was just refluxed In a flask to extract it

Housane - 30-3-2021 at 13:02

Is it worth repeating without the 2nd reflux as I got the 2 layers as described in the video?

DraconicAcid - 30-3-2021 at 13:12

If the gloves you're starting with contain di(ethylhexyl)phthalate, then you would have ethylhexanol as a byproduct, which would be upper orange layer.

Syn the Sizer - 30-3-2021 at 15:42

That would make sense. I have never synthesized the acid from gloves, I just buy it.

Housane - 30-3-2021 at 16:56

Ok, thanks for the help I’m going to try without 2nd reflux again.

Do you think the white is waste as well or product, it has a minty kinda air freshener smell