Activated carbon filters chlorine through a process called catalytic reduction, a chemical reaction where the carbon surface facilitates the removal of chlorine.
Here's a breakdown of how it works:
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Adsorption: Initially, chlorine molecules (Cl₂) present in the water are attracted to and adsorbed onto the large surface area of the activated carbon material. This is a physical process where the chlorine adheres to the carbon.
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Catalytic Reduction: The activated carbon acts as a catalyst, meaning it speeds up the chemical reaction without being consumed in the process. In this reaction, the chlorine molecules (Cl₂) react with the carbon surface and water (H₂O). This process breaks down the chlorine into chloride ions (Cl⁻), which are harmless, and other byproducts. The general reaction is as follows:
Cl₂ + H₂O + C -> 2Cl⁻ + 2H⁺ + CO
Where 'C' represents the activated carbon surface.
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Electron Transfer: Activated carbon essentially acts as a reducing agent, donating electrons to the chlorine molecules. This electron transfer reduces the chlorine, converting it from a harmful disinfectant to harmless chloride ions.
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Removal of Chlorine Taste and Odor: The catalytic reduction process not only removes the chlorine but also eliminates the unpleasant taste and odor associated with it.
In summary, activated carbon doesn't just trap chlorine; it chemically transforms it into a less harmful substance through catalytic reduction.
