A friend (seriously, I do A/B's) recently did a STB under my supervision.
For some reason the naphtha turned red and recrystalization and sodium carb washes are not getting rid of it.
We used naphtha and only naphtha as the solvent.
After I left he tried a heptane recrystalization (hot) and the bestine turned red as well. He has tried both freeze precipitation and slow evap recrystalizations with red crystals forming each time.
It does not appear to be silt (we used powdered RB), but rather something that has dissolved in the naphtha. It's very strange and I've never seen anything like it with MHRB.
Last night he added room temperature heptane and dissolved all the spice. I told him to let it sit overnight to see if any of the red would fall out. If it does, it probably was just silt, but if not (and I don't think it's gonna) then I have no idea what's going on. I mean the crystals are brownish-red. It's not like there is a pile of red onthe bottom and xtals growing on top.
Any idea's on how to get the red out?
For some reason the naphtha turned red and recrystalization and sodium carb washes are not getting rid of it.
We used naphtha and only naphtha as the solvent.
After I left he tried a heptane recrystalization (hot) and the bestine turned red as well. He has tried both freeze precipitation and slow evap recrystalizations with red crystals forming each time.
It does not appear to be silt (we used powdered RB), but rather something that has dissolved in the naphtha. It's very strange and I've never seen anything like it with MHRB.
Last night he added room temperature heptane and dissolved all the spice. I told him to let it sit overnight to see if any of the red would fall out. If it does, it probably was just silt, but if not (and I don't think it's gonna) then I have no idea what's going on. I mean the crystals are brownish-red. It's not like there is a pile of red onthe bottom and xtals growing on top.
Any idea's on how to get the red out?