Be it a filter jug, a filter tap or a water purifier, most water filtration products purify your water by running it through a cartridge.
According to different filtering purposes and requirements, the material in the cartridge will vary. Here are the main types of filter material you can find.
Activated carbon is the porous version of normal charcoal.
The tiny pores on the surface of activated carbon allows it to react readily with organic chemicals in unfiltered water, thus purifying the water.
You can find activated carbon in most of the cartridges available on the market.
Activated carbon also plays a role in removing odour and chloride from the water.
But since activated carbon itself contains a considerable amount of impurities, bacterial growth in activated carbon cartridges is difficult to avoid.
Therefore, more frequent cartridge replacement is needed.
(Image: Apex Instruments)
Filter cartridges made with diatom ceramic can filter out impurities like sediment, chlorine, lead, and some microbes present in unfiltered water.
Users should clear the impurities on the cartridge regularly. A brush, a scouring cloth and some rubbing should do the job.
Hollow fibre membrane
(Image: ForwardOsmosis Tech)
Hollow fibre membrane is made of artificial polymers like acrylic.
The filaments of the membrane are long and porous, which traps bacteria, fungus, parasites, rusts and sediment.
Non-woven fabric’s complex structure and thickness makes it a suitable material for water filtration.
This material is used to filter out larger impurities like grit and sand.
Ion exchange resins
Ion exchange water filters are commonly used to reduce water hardness (ie. the water’s mineral content).
Coffee lovers are no stranger to this kind of water filter, since hard waters ruins the taste of coffee.
This kind of water filter removes mineral ions like calcium, magnesium ions with a polymer which binds with positive ions. Some ion exchange filter can also filter out nitrates and sulphates.