Safety vs Efficiency of Non-Polar CBD Crystallization Solvents

Hello all, I’ve seen this subject come up in part of other threads, but feel it would be useful to have a more focused discussion.

For those of us using Non-Polar Solvents for CBD precipitation, what is your experience and feelings on Hexane, Heptane, and Pentane.

I have used both Pentane and Hexane with success and find that Pentane is usually the solvent of choice for many processors. However, does anyone have experience using heptane with success?

Pentane has generally yielded a faster rate of precipitation, given that the final product being a chunky isolation of small crystal formations is not a deal breaker, often only requiring 12-24hrs of cooling.

If one was to try and lower their risk of combustion, then I find myself looking more towards something like heptane.

Lower Explosive Limit comparisons for the three that I have seen would be:

Heptane: 1%
Hexane: 1.1%
Pentane: 1.4%

Closed Cup Flash Point comparisons:

Heptane: -4c
Hexane: -26c
Pentane: -49c

Boiling Point comparisons:

Heptane: 98c
Hexane: 69c
Pentane: 36c

All three are Class 3 Flammable Liquids

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Yes I have been able to make isolate on relatively large scale with all of these solvents. I prefer pentane because it is the easiest to remove from the product and I remove every ppm of pentane and I am comfortable working with explosive/dangerous shit lol.

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Do you know what ppm levels you have seen after using heptane or hexane?

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I was able to get it below the legal threshold for oregon which i think is 4000-6000 ppm i know that hexanes is the lowest and heptane threshold is = pentane threshold

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pentane is ~much~ easier to purge.

whole process should be done in vessel(s) , any pentane vapor should be condensed / cold trapped keeping explosion risk near zero.

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So where does the pentane go when your extracting in a c1d1 room? Does it Normally get duct outside?

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recover it with a condenser. why waste it?

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Was a there a difference in yield? Correct me if I am wrong, but theoretically pentane should be a better solvent - lower solubility than hexane or heptane - in terms of yield.