How long do these winterization membranes last when properly maintained?
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These Dupont filmtec sw-30 2540 membranes are not compatible with ethanol. The ethanol that permeated the membrane came out a dark brown color. This was during a test with pure ethanol.
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Did you wash them with water first? That brand, i believe, comes packed with a colored preservative.
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I ran the membranes with water briefly, I was chasing leaks with water for a day before I dried out the system and used ethanol. Perhaps I did not flush enough water through to remove the preservative. Iāll wash some water through and try some more ethanol.
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I will say, Iāve used SW-30 before and while I didnāt think the performance was great, I didnāt see what youāre showing here.
With a dry packed membrane, i use the following procedure:
Run for 30 min with water at 100 psi
Run for 30 min with 50:50 water:eth at 100 psi
Run for 30 min with eth at 100 psi
Then, bring to working pressure and test flux.
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By the way, read the fine print of that amazon pageā¦ It is not DuPont SW-30, but rather an element by Acqua Primo they are selling as a ācompatible replacementā for the Dupont branded one.
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Iād also think that EtOH would swell some membranes, reducing funcitonal pore size
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That is definitely, almost universally, the case.
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I want one for butane that takes up a 2āx2ā, or 3āx3ā footprint. Can they be ran vertically?
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4800 gets the lid of a slant mat column broken off the steel hinge and through the adjacent wall, winch included.
Well thatās a good unit of of measurement to calculate how much psi I need to get in the game with Elon and Jeff
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MSI. Ksi only gets you up to Branson altitudes
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My skid has the housing vertical and is 30"x33.5"
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The 1812 (1.8" x 12") or 2520 (2.5" x 20") are the main sizes that would fit in that constraint.
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My bench top units will run 15 gph - 40k (10% off with glg discount) and 30 gph -65 k (10% off with glg discount)
These are full c1d1 compatible
The 15 gph will look like this while the 30 is slightly bigger with bigger housings
https://www.instagram.com/p/CP_2WIxhe7m/?utm_medium=copy_link
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A further example of how chemistry matters more than particle size. Cellulose acetate continues to show the unusual behavior that it selectively rejects chlorophyll more than cannabinoids ā while most membranes, even supposedly super tight ones, let a lot of chlorophyll through even while rejecting cannabinoids.
This nominal 10,000 Da cellulose membrane from Alfa Laval rejected significant amounts of chlorophyll (though unfortunately not all of it). Meanwhile, a 1,000 Da PES membrane did not reject nearly as much. You would think a 10,000 Da membrane would reject no color at all, so itās interesting to see this behavior.
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Iāve mentioned something to Zev a few times about wanting a tane/pane one 
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So my local water dept is auctioning this TFF set up. Idk if millipore pellicon has as many membrane options since Iāve only ever used them for biosciences (protein and virus concentration) but to a hobbyist and/or small lab this might be a good buy. Iām considering it myself. Always the risk of broken shit. I want it just for the peristaltic pumpā¦
Sorry Iām not intending to hijack the thread just didnāt think this deserved itās own post
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It probably could be used with flat sheets from different brands. Though the pump supplied could only support low-pressure applications.
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The silicone lines tend to balloon around 28-30 psi. This would be a low pressure unit yeah.