Chemistry Forum

Hello,
Some time ago, I spoke to an electrical engineer about how using alcohol on PCBs to clean of flux residue worked well, but left some small, white, particulate matter behind. Less particles with 90% IPA. He suggested that I purchase an azeotrope (I think is the word that he used), of IPA. As in, an ion free container of IPA.
At the time, the world was in turmoil and IPA prices were through the roof, so I waited for them to come back down.

Now that I search online for this stuff, I cannot find it. I tried the CAS number, the name, everything I could think up. I managed to find anhydrous IPA, but I'm not sure that's what I'm looking for.

So, is 99% pure IPA what I'm looking for? Or maybe you know better how to search?

Thanks!

PS: I cannot ask the EE as both of us are not part of the social circle where we were speaking of the matter. Why is another, long, story.

An azeotrop is a mixture of 2 or 3 compounds, which cannot separate at a certain temperature by destillation.

https://en.m.wikipedia.org/wiki/Azeotrope_tables

For IPA (2-Propanole) it is 87,7% w.w and boiling point is 80,4° C

For your purpose for cleaning something buy 80% to 90% IPA, that is what the electrical engineer meant. 99% pure is to expensive. No need.