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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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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You are right but treuth is I think very few have them
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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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Give me a chance to quote one to you
ā Roguelabā 
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Iāve used lots of methanol without explosions (so far?)
But I mean you buy it in plastic jugs that arenāt rated, and their caps donāt even have fancy seals on them. Itās pretty inert unless its hot.
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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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Labs used to modify fridges for this reason. Explosions are common
ā3) 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
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Certainly not arguing itās not gonna light up if you expose it to poor conditions.
I guess you already said it earlier, itās much less volitaile than poorly stored hydrocarbons.
But, youāre 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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I never considered a freezer as an ignition sourceā¦ Been doing pentane crystallizations in a chest freezer for a while now. Guess Iāll have to rethink what Iām doing, because that would be an expensive/dangerous mess.
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These guys get it! 
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 wonāt start a fire. 2 lines of defense.
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What is the emulsion layer between brine and pentane when doing LLE? It looks like the waxy shit inside of a lava lamp
Iām guessing itās the h20 and Ptane fighting to separate?
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IDK I didnāt 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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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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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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Basically the gums and other gunk are acting as an emulsifier, and form an emulsified mixture of organic and aqueous molecules thatās heavier than pentane and lighter than water
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What would cause my water to grab onto pentane? I lost 2 liters of pentane and Iām pretty sure it just mixed into the water. The water is kinda thick, but doesnāt seem very sticky to the touch so Iām not exactly sure what happened
Huh ?
What temperature are you working in and what temp are your solvents
?
Should not mix with water
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