Pentane LLE

Hash and Stuff Pre/Post-Processing
21

:joy: are you serious putting methanol in atex freezer
I have never even given it thought
Any real danger we should consider ?

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22

I mean, putting flammables in a storage that is not rated for flammables.

Prolly not gonna blow up like poorly stored hydrocarbonsā€¦depending on volumeā€¦but still.

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23

You are right but treuth is I think very few have them

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24

@potguru1 has flammable compatible -40C Freezers :eyes:

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25

Ive been using only methanol for over 5 yrs, it works alot bettwr than etho in my opinion. Good ventilation and its all good

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26

Give me a chance to quote one to you
ā€œ Roguelabā€ :+1:t3:

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27

Iā€™ve used lots of methanol without explosions (so far?)

But I mean you buy it in plastic jugs that arenā€™t rated, and their caps donā€™t even have fancy seals on them. Itā€™s pretty inert unless its hot.

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28

https://www.biomcn.eu/wp-content/uploads/2014/03/SDS-methanol-20160901.pdf

The SDS disagrees with your opinion.

Methanol is indeed quite flammable.

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29

Labs used to modify fridges for this reason. Explosions are common

ā€œ3) Modified Domestic Refrigerator
This type of refrigerator is a domestic unit in which sources of ignition within the storage
compartment have been relocated or removed. Only manual defrost refrigerators can undergo
this modification process. The self-defrosting models cannot be successfully modified to provide
even minimum protection against vapour ignition. The following are the minimum procedures for
modifying a domestic manual defrost refrigerator:
ā€¢ relocate the manual temperature controls to the exterior of the storage compartment ā€”
all points where capillary tubing or wiring formerly entered the compartment must be
properly sealed;
ā€¢ remove all light switches and light assemblies and seal all resulting openings; and
ā€¢ replace positive mechanical door latches with magnetic door gaskets.ā€

taken from https://ehs.utoronto.ca/wp-content/uploads/2015/10/Refrigerators-Updated.pdf

https://ehs.msu.edu/news/2015-07-10-fridge-explosion.html

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30

Certainly not arguing itā€™s not gonna light up if you expose it to poor conditions.

I guess you already said it earlier, itā€™s much less volitaile than poorly stored hydrocarbons.

But, youā€™re right. Creating then eliminating fireballs is a less than ideal way to run a lab. Might as well just avoid the fireball step altogether.

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31

I never considered a freezer as an ignition sourceā€¦ Been doing pentane crystallizations in a chest freezer for a while now. Guess Iā€™ll have to rethink what Iā€™m doing, because that would be an expensive/dangerous mess.

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32

These guys get it! :+1:t4:

33

Ethanol starts to off gas at -5 f. The rating for a freezer that will work is C1D2. You need to have a safety system that consists of a oxide fume sensor and a temperature probe connected to a central control module. This provides a full proof safe system in case of spills and temperature monitoring. If it senses fumes it shuts down completely. If the temperature is to high. -4 and so on the unit shuts down so the off gassing wonā€™t start a fire. 2 lines of defense.

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34

What is the emulsion layer between brine and pentane when doing LLE? It looks like the waxy shit inside of a lava lamp
Iā€™m guessing itā€™s the h20 and Ptane fighting to separate?

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35

IDK I didnā€™t like using pentane/brine for crude LLE I use hexane only now.

Although pentane against the alcohol of your choice provides a lot of clarification to your alcohol fraction. With some loss of cannabinoids to the pentane layer.

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36

We were using hexane, then went to pentane because the recovery rate was faster and it has been working alright. I still want to do heptane. I hear great things about heptane

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37

That would depend on what pH the aqueous phase is inā€¦ But in both cases, I think they mostly attack phosphatides, which we typically see as red/pink oxidations. More on the subject:
https://lipidlibrary.aocs.org/edible-oil-processing/introduction-to-degumming

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38

Basically the gums and other gunk are acting as an emulsifier, and form an emulsified mixture of organic and aqueous molecules thatā€™s heavier than pentane and lighter than water

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39

What would cause my water to grab onto pentane? I lost 2 liters of pentane and Iā€™m pretty sure it just mixed into the water. The water is kinda thick, but doesnā€™t seem very sticky to the touch so Iā€™m not exactly sure what happened

40

Huh ?
What temperature are you working in and what temp are your solvents
?
Should not mix with water

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