4 ms·
The standard Brita pitcher filter is a mix of granular activated carbon (from coconuts), and the ion exchange resin you talk about.
by brittohalloran 13y ago
The standard Brita pitcher filter is a mix of granular activated carbon (from coconuts), and the ion exchange resin you talk about.
- tehwalrus 13y agoThanks, I didn't know that! What does the activated carbon do?
- nine_k 13y agoIt's chemically inert, but has a very fine porous structure (thus 'activated'), so it works as a mechanical filter that adsorbs anything large enough, like bacteria and even very large molecules.
- fsck--off 13y agoActivated carbon, also known as activated charcoal, was the useful ingredient in "universal antidotes". Although the mixture (see link) is no longer used, activated charcoal still is. http://www.medilexicon.com/medicaldictionary.php?t=4805 http://www.medilexicon.com/medicaldictionary.php?t=4805
- oasisbob 13y agoIt's chemically inert [...] so it works as a mechanical filter that adsorbs [...] Because adsorption is a consequence of surface energy and weak bonding, I believe it's considered to be a chemical process, not a mechanical one.
- nine_k 13y agoRight, the distinction is fine here. Adsorption is due to weak bonds that form between molecules of a surface and a fluid. AFAIK this bond is not a 'new' chemical bond since it does not break / replace existing chemical bonds in both the adsorbed molecule and surface molecules. Rather, in the case of carbon at least, the 'bonds' are the van der Waals forces.