Question

Give two uses for the Bone Charcoal.

Answer 1

Bone charcoal is a type of porous, black granular material made out by charring animal bones. It includes $57 - 80\%$ tricalcium phosphate, $6 - 10\%$ calcium carbonate, $7 - 10\%$ carbon.

Complete step by step solution:
It is from cattle and pig bones primarily the bone charcoal is produced, the bones taken are heated in a completely sealed vessel with very low amount of oxygen as it affects the quality of the product particularly its absorption capacity.
The main and primary use of bone charcoal is filtration and decolourisation.
Water Treatment:
Bone charcoal is used in water treatment as the tricalcium phosphate present in it is capable of removing fluoride and metal ions from water and make it usable for various requirements including drinking. Bone charcoal is considered as the oldest water defluoridation agent. As bone charcoal is cheaply and locally available it is still used in many places.
Sugar Refining:
It is also used in sugar refining as a decolourizing and deashing agent as sugar cane consists of more coloured impurities. As bone charcoal is having low discoloration capacity it has to be used in large quantities. It is also capable of removing various inorganic compounds, mainly sulphate and the ions of calcium and magnesium.
Black Pigment:
It is used as black pigment in artist’s paint, calligraphic and drawing inks as well as for various other artistic applications because of its deepness in colour and high tinting strength.

Note:
In bone charcoal by heating itself most of the organic materials are removed and was collected as Dippel’s oil which remains as activated carbon in the final product. The heating of bone in presence of a high amount of oxygen gives bone ash which is entirely different from bone charcoal.