experimental
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Long term chemical storage
I'm having issues with storing formaldehyde.
I bought it from a chemical reseller, and kept it in the plastic bottle it came in.
However, knowing it is volatile I decided to periodically check the bottle weight every month or so.
Turns out, it is steadily losing weight at a rate of around 0.1g/month.
I wrapped some teflon tape around the bottle thread, and I am considering storing the bottle in a secondary container with sodium hydroxide to
neutralize any escaping fumes.
What would you do in such a situation?
Spending more time cleaning glassware than doing the reactions
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BromicAcid
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What is the total quantity? Obviously if you have a kg of material and you're losing 0.1 g/month then it's much less of an issue than if you only
have 10 grams of material. Also, what is the concentration and what is the material of construction of the bottle?
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DavidJR
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Personally I have 37% formaldehyde stored in a PE bottle and I'm not worried about it. If it bothers you then transfer it to glass bottles.
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experimental
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It's 100mL of 37% formaldehyde, stored in an HDPE bottle.
I'm more worried about it than other reagents because it's the only carcinogenic substance in my lab (assuming DCM isn't).
For now I'll just wait and see if the teflon stops the leak. Thanks.
Spending more time cleaning glassware than doing the reactions
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DavidJR
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Quote: Originally posted by experimental  | It's 100mL of 37% formaldehyde, stored in an HDPE bottle.
I'm more worried about it than other reagents because it's the only carcinogenic substance in my lab (assuming DCM isn't).
For now I'll just wait and see if the teflon stops the leak. Thanks.
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DCM is definitely carcinogenic.
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happyfooddance
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If you are worried about the carcinogenic risk from a 100ml bottle of formaldehyde solution that is leaking 0.1g/month...
Let's just say your fears are overblown.
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Mr. Rogers
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| Quote: | | It's 100mL of 37% formaldehyde, stored in an HDPE bottle. |
If you're worried about health risk, a 100ml bottle is easy to fit into a secondary container. I commonly use pint and liter mason jars for this,
with special lids that have silicone seals:
https://www.amazon.com/Masontops-Tough-Premium-Reusable-Stor...
I double-contain 32% HCl, 30% ammonium hydroxide, formaldehyde, mercury, and iodine successfully like this. The wide-mouth liter mason jars can fit
250ml Boston rounds or 250ml "vitamin bottles", the pint jars can hold smaller bottles.
To stop glass bottles "clanking" around inside the mason jars, you can wrap them in paper or plastic bags, which ever is appropriate for what you're
storing.
[Edited on 1-1-2019 by Mr. Rogers]
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macckone
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There is a good reference on formaldehyde in the library.
If it is in solution then you are probably getting more methanol coming off than formaldehyde.
It tends to polymerize rather than evaporate.
Paraformaldehyde tends to release more than the liquid.
Having said that, if you have a formaldehyde odor than store it in a secondary container or ventilate the storage area.
Ventilation is required in the fire code.
The recommended level is 16ppb, which is pretty low.
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macckone
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To put it in perspective, .1g is about 75ml of gas. A 1M x 1M x 2.5M room (3ft x 3ft x 8ft) is 2500L
30000 ppb. which is a very high quantity but most buildings have at least .75 air changes per hour.
Meaning 540 air changes per month. So at most you would get 55ppb accumulation in a normally ventilated area.
My basement is 'well ventilated' at least 15 ACPH.
The fan rating is 1200CFM but I leave it on the 300CFM setting.
Chances are your storage area is closer to 3 ACPH which would keep the formaldehyde below 14ppb.
And if your area is larger than perscribed the greater volume of air will keep it even lower.
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j_sum1
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Thread Pruned
1-1-2019 at 18:24 |
happyfooddance
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I don't think this qualifies as "room", I think I may require a larger coffin!
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macckone
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One would hope that you are storing chemicals in a dedicated area rather than your living room. Dedicated rooms for storing stuff are usually called
closets. But closets may not have dedicated air circulation.
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j_sum1
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Thread Pruned
24-1-2019 at 20:36 |
woelen
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Thread Moved
23-5-2019 at 11:44 |
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