Is there a centralized source for winterization membrane solvent compatibility? I am looking to use non-traditional/green solvents in extraction and I know they are weird with what materials they can be used with.
For membrane solvent compatibility specifically? Not to my knowledge. There are sources solvents and plastics though. You’d have to tell use which solvents you’re using and/or which filters.
Cotton, borosilicate, and PTFE micron filters are pretty resilient when it comes to solvents.
Which solvents are you looking for specifically? Should be able to source them for you, we are located centrally in the US (Chicago suburbs)
Turns out you also have to worry about how the membranes are affixed to the housings….(see below)
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No.
I’ve purchased custom-rolled membranes from specialty companies that were claimed to be resistant to a specific solvent, but when they were introduced to that solvent, all of the adhesives dissolved into the process stream.
I’ve talked to membrane vendors who sell to this industry specifically who did not see this as a problem until I pointed out that we don’t want random polymers in our finished products, and neither does the regulator.
Some of the larger manufacturers will give you some compatibility details. Most will not. The ones that do usually charge you “oh fuck that noise” prices for their membranes.
If you’re lucky, and you get a list of the materials of construction from the vendor, that’s great! Right? Not necessarily.
There are frequently multiple grades or types or formulations of given materials. There are variations/formulations of some rubber based materials that are fine with alkanes, and there are some (uncommon ones) that are not.
Temperature also has an effect on compatibility.
Most manufacturers will not tell you what type of glues, wraps, or other materials are in their elements. I suspect that many don’t know because their membrane production is farmed out to other companies or they just don’t care.
There are a handful of common polyurethane based glues used in membrane production. Some are fine with certain solvents or parameter ranges, others are not.
If you get the list of materials, and you check the good ol cole-parmer compatibility table, you may have an idea if something is worth rolling the dice on.
But just because something is listed as an A compatibility does not mean that your specific material from your specific vendor will not dissolve on first contact, and that it will not leach something into your process stream.
And just because something is listed as a D compatibility does not mean that it will not work in your application. Notice that all compatibility tables list a “this is for informational purposes only” type statement? There’s a reason for that. They’re all compiling data from a boatload of sources of various quality.
Material compatibility of materials and various solvents is an extremely deep PhD level topic.
Good luck.
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Also, good luck with this.
If your job is “winterization” aka excluding lipids, waxes, and other cold-precipitatable nasties, you may find that membrane that works fantastic in solvent A may do a completely shite job of it in solvent B.
In solvent A it may exclude functionally 100% of what you want to exclude. In solvent B it may allow a significant % of them forward. And it may do it at 1/10 of the total rate.
Even if A and B are alcohols. Even if you keep temperature and pressure constant.
Even if the vendor told you it should work just fine … they got your money, didn’t they? Problem solved as far as they are concerned.
Considering that you’re trying to exclude at least two or three classes of compounds in differing molecular size ranges… it’s somewhat amazing that the industry has found any that work at all.
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lol ngl based on your two posts i’m just abandoning that direction.
d-limonene, acetic acid, dipentene, and then a few others i don’t really want to mention right now.
if you can get me a membrane/glue that works we’re willing to pay full price all that shit.
Probably a good call.
If you decide to get creative with membranes, and you can find a membrane flat sheet that works for your application, Henkel adhesives would probably be able to recommend a glue that would work.
If I had to pick a number out of the air, I’d say it’s a $100,000 - $500,000 venture to find, validate, and select a membrane that will work for a novel application.
Might be less, could be a lot more. On the low end, that’s assuming you build your own skid/test rig, do all of your work in-house, and your hours are “free.”
And there are zero guarantees of success. We tested a LOT of membranes for a certain application and never found one that met our performance targets, and the closest ones were priced at “lol no” levels.
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Not sure if you are still going to go that direction with the membranes but I will shoot you an email with our pricing sheet for solvents if that is cool. My email is lukec@shopbvv.com, if you want to send me an email or DM me your email I can send over that pricing sheet!