Uploaded December 2016 | Updated September 2026, 3 weeks ago
We synthesize and redistil pure benzene. Unfortunately, that wasn't really from using a PET method. Seeing as the PET to Na terephthalate to benzene method was so much work for such little reward, we try a different route and try a 1 pot reaction from PET to benzene. Thank you to Krisztián Szirtes for suggesting the 1 pot reaction (I believe you originally suggested a one step reaction then I made more work for myself by splitting it in two. But hey, at least I managed to actually get some benzene from the 2 step method!)
I didn't mention it in the video but I also think using a low melting NaOH/KOH eutectic to prevent charring could also work. Thanks to piranha031091 for this idea. The eutectic is 165°C at 50% NaOH, but I think having a melt temp just above the boiling point of ethylene glycol (199°C) would help the hydrolysis along better. So a melt temp of ~200°C is more than 100°C lower than the mp of NaOH (318°C) so that should both help prevent charring and prevent terephthalic acid sublimation. But will it be enough to get good benzene?
We synthesize and redistil pure benzene. Unfortunately, that wasn't really from using a PET method. Seeing as the PET to Na terephthalate to benzene method was so much work for such little reward, we try a different route and try a 1 pot reaction from PET to benzene. Thank you to Krisztián Szirtes for suggesting the 1 pot reaction (I believe you originally suggested a one step reaction then I made more work for myself by splitting it in two. But hey, at least I managed to actually get some benzene from the 2 step method!)
I didn't mention it in the video but I also think using a low melting NaOH/KOH eutectic to prevent charring could also work. Thanks to piranha031091 for this idea. The eutectic is 165°C at 50% NaOH, but I think having a melt temp just above the boiling point of ethylene glycol (199°C) would help the hydrolysis along better. So a melt temp of ~200°C is more than 100°C lower than the mp of NaOH (318°C) so that should both help prevent charring and prevent terephthalic acid sublimation. But will it be enough to get good benzene?
