Sciencemadness Discussion Board

Hexane or Pentane?

ausnewbie - 4-7-2018 at 03:54

Silly question and unusual situation,

A friend of mine is clearing out a vacated lease and the old tenant ( mining analysis company) left behind a lot of stuff, but there are some reagents, in particular unopened bottles of 2.5 litres Pentane and anhydrous hextane in the back of a storeroom.

Hes asked if im interested, and I can probably see a use for HEXANE, as I mainly work with essential oil extracts and neutraceuticals (thymoquinone and curcuminoids) so a hexane extract could be of interest, but not necessarily on my radar.

Anyway I thought Id throw it to the hive mind and look for thoughts and opinions???

I know enough - to know I dont know enough. :-)

AN

[Edited on 4-7-2018 by ausnewbie]

Sulaiman - 4-7-2018 at 04:23

I don't know if the pentane is useful to you,
but a bottle that can store pentane surely is worth saving ?

I'm an OC noob but I doubt that there is much difference in the chemistry of pentane and hexane,
just the b.p. difference which could be useful ?

Metacelsus - 4-7-2018 at 04:26

Hexane is quite useful as a nonpolar solvent, but if you're using it you need to have adequate ventilation. The vapors can cause neurotoxicity (this is due to a toxic metabolite, 2,5-hexanedione). Likewise, if you plan to make essential oil extracts, all traces of hexane must be removed before use.

Pentane is less toxic ( see: https://www.ncbi.nlm.nih.gov/pubmed/7426474 ) but more flammable.

[Edited on 7-4-2018 by Metacelsus]

ausnewbie - 4-7-2018 at 05:46

thank you guys they were my thoughts as well.
Hexane has some potential (outside or in my makeshift fume hood), but I dont think pentane brings any more benefits. although a boiling point of 35C is useful Vs 68c ( imho).

Think I'll opt for the hexane. Thanks to all of you all for your thoughts.

AN

alking - 5-7-2018 at 11:19

Pentane is essentially hexane with a lower boiling point from an application standpoint, and as mentioned it is probably less toxic. If doing extractions Pentane would be preferred as it's easier to purge due to that low BP, although while doing the extraction you'll lose a little more for the same reasons.

edit: I should clarify that I was referring to ROOM TEMPERATURE extractions. If you're trying to speed it up with heat then hexane is probably better.

[Edited on 5-7-2018 by alking]

Refinery - 27-6-2020 at 11:49

This was discussed by passing in another thread, but I'd like to ask is pentane very useful at all to dissolve anything used in basic chemistry? It is written that it dissolves mostly alkanes?

DraconicAcid - 27-6-2020 at 12:12

Pentane is an excellent solvent for many non-polar substances, including hydrocarbons, some organometallics, and halogenated hydrocarbons. It's also a good antisolvent for moderately polar organic compounds- dissolve them in a polar organic solvent, and add pentane to get them to crystallize.

[Edited on 27-6-2020 by DraconicAcid]

Refinery - 27-6-2020 at 12:53

Why I haven't seen common hydrocarbons being used as solvents more often then?

Bedlasky - 27-6-2020 at 15:06

You can use them both, so take both bottles.

draculic acid69 - 27-6-2020 at 16:53

Both useful.