Filtering Ethanol Solution to 0.45um

  • Thread starter cronicoldguy
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I am having no luck with Buchner Funnels. I always have DE bypassing filter paper. It becomes a total shit show inside rotovap once solution becomes very concentrated. I have come to the conclusion I need a Colour Remediation Column, (CRC).

Although I am considering integrating Bleaching Clay into my SOP, presently I only use DE and Carbon for remediation, no uglies.

Using ceramic Buchner Funnels, the neck of funnel doesnt penetrate vacuum flask below vacuum inlet. This allowed solution to be drawn into vacuum pump, resulting in lower yields. So I switched to glass perforated Buchner Funnels (not sintered). But using these funnels, DE is bypassing filter paper.

So I need a filter system with a mechanically sealed filter. A CRC meets this critertia. But for the average private individual, the expense is too great, $2200+CAD. So I have been looking at Closed Loop Extractors. These can be had for around $600CAD. I only really need one filter medium inside the column which would be a cake of DE. Bleaching Clay as well if I decide to use it.

There are disposable 0.45um capsule filters available. But they are expensive. Approximately $50CAD per filter and they are a 'one shot deal'. So not very cost effective.

Given my SOP for filtering is basic, do you guys think this will work good? Any tips or suggestions? If I decide to use Clay as well, could I just add another spool and sintered plate to it? Also, I cant find filter paper below 1.5um. Does it exist? I want to filter down to at least 0.45um. I am also hoping I can just use CO2 or N2 cartridges to pressurize the column.
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