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Is it ok to use polypropylene recipients with NaOH and water?

L

leeroyeleusis

Rising Star
I wanted to use fancy glass recipients for an A/B extraction, but these are EXTREMELY expensive where i live and i can't really afford anything like that at the moment, so with some research i found out that polypropylene is resistant to most chemicals used in this process, and i've found some pretty cheap 3,5l polypropylene bottles. Regarding the chemicals, the main "important ones" i'll use are acetic acid, xylene and NaOH. I've read polypropylene is resistant to xylene at room temp but can dissolve at around 150ºC, and that polypropylene itself starts degrading in temperatures above 100ºC. The main problem here is, when NaOH it's added to water, it releases a lot of heat, i'll be using 65g of NaOH in 2,5l of water, will the polypropylene resist this? I'm almost sure the temperature will not rise over 100ºC but i'm no expert so i prefer asking instead of risking.
 
Varallo said:
Just use common glass containers like drinking glasses or use glass food containers such as bottles, there is zero need for fancy glassware.
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Can these be safely heated? My main concern here is the exothermic reaction with the NaOH. I thought of using stuff like empty vodka bottles for example, but the thing is i'm not sure if it's safe.
 
you know, you dont have to use NaOH, carbonate works too once your DMT salt is in solution. also, you can add hydroxide for 80% of the way, then carbonate for the final bit, . its only an issue for plastics to be in contact with NaOH for sustained periods of time while hot. Again though carbonate is fine for resistant plastics like PP or HDPE. It also bubbles, but not that much, many people seem to be preffering it these days over lye.

When dissolving NaOH, add it to some ice cubes, its a perfect method for producing concentrated solution. also, adding dry lye to water in a plastic container will produce localized saturated hydroxide brine if it reaches the bottom before dissolving, which is very hot, and very destructive to both plastic and possibly spice too.

Make some concentrated hydroxide solution from mixing ice and lye, and add slowly until your soups pH changes even slightly. pH is logarithmic so shifting from pH of 1 or something, to 3, represents like 90% of the acid having been neutralized. then do the rest with carbonate so any excess base is harmless carbonate and not lye.
If you cant test the pH then take a small amount of soup record how much base it takes to cause it to change color which will happen after it passes neutral, and use that number to undershoot the main soup so you can push it over the line with carbonate.
 
I personally use HDPE plastic bottles and have never had an issue with plastic melting or getting mixed into the extraction when using NaOH, water, Phosphoric acid, and naphtha
 
manifest_jynx said:
I personally use HDPE plastic bottles and have never had an issue with plastic melting or getting mixed into the extraction when using NaOH, water, Phosphoric acid, and naphtha
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The thing is not about dissolving your containers but about the micro plastics/colorants and inhaling/eating them. These things are not visible to the naked eye but do appear to have negative effects on your health.

I advise anyone to only use glass for extracting.
 
theres many different kinds of HDPE and PP, i have some really nice autoclavable PP chemical reagent bottles. i dont imagine there would be any issue with those. but re-using like, a shampoo bottle or something? thats sus. and yeah, glass is always best. when in doubt, save your pasta sauce jars. anything that was canned, i.e preserved specifically by heat not preservatives like acid in pickles, jars like that are very decently heat resistant. not, boil like its a beaker but, can probably microwave them, good. its not like you have to seriously chance it either you can put the jar in a ziplock bag for in case of a spill/break, ziplocks are usually PP and will contain a leak long enough for you to address it.

If investing in some GL45 heat resistant borosilicate bottles (safe for oven, autoclave/PC, microwave, sand bath, water bath, oil bath to a point, sometimes heating directly to induce boiling but not 100% sure if thats a standard maintained for all of them), not all of them are properly airtight. some are meant to be used with teflon washers, or, have the pouring lip removed to seal properly. to test it out, shake some iso, ethanol, or naptha in the bottle when closed and take note if it leaks. i have a few that leak methanol and acetone only, but water is fine. the pouring ring isnt flush with the glass though, all but one became reliable upon removing the pouring lip ring.

Also important note when buying Gl45, dont be afraid to search in lab supply website/stores. sometimes they are stupidly expensive, but other times they are stupidly cheap, way cheaper than even the fake unbranded soda-glass ones sold on amazon/china. you should be able to get 1L bottles for $12-15 or less from places that sell fancy mega-quality beakers for like $1/ml capacity, i got my high quality german branded ones for between $3-10 for 50-1000ml from a place that mostly sells ultra high end premium lab gear, that makes you question how an ordinary beaker made of borosilicate, could cost hundreds of dollars each, without any special properties just, somehow better quality.
Anyway, its truly random so, give it a shot. the high quality ones, especially if they are branded, are well worth it and will last a lifetime.
 
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