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How can bone black be used as a filter aid?
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Tap water filtration system.
Bone black, also known as bone char, functions as a filter aid primarily through its role as a decolorizing adsorbent. Produced by heating bone in a limited supply of air, this material consists of approximately 12 percent elemental carbon, with the remainder composed mainly of calcium phosphate and calcium carbonate.12
In industrial applications, particularly in the refining of raw sugar, bone black is used to remove colored impurities from liquids. Its porous structure allows it to effectively adsorb these impurities, clarifying the solution as it passes through the material.21