Question

Bone charcoal is prepared by destructive distillation of bones.

Answer 1

As we all know that bone charcoal is a black, porous and granular substance which is produced by heating the bones at high temperature and low oxygen concentration and destructive distillation is basically a process of decomposition of organic unprocessed materials.

Complete step by step solution:
We all know that the Bone charcoal or commonly called as animal char is a black, porous and granular substance which is produced by heating the bones of animals at high temperature and low concentration of oxygen. Pig and cattle bones are majorly used to make this material except their skull and spine because they can result in Creutzfelt-Jakob disease which is a degenerative disorder of the brain resulting in memory loss and death.
Let us talk about the preparation of bone charcoal. These animal bones are heated in a sealed vessel by the process called destructive distillation, at a temperature of about ${700^ \circ }C$ and the oxygen concentration is kept very low as it can affect the adsorption quality of the product. The organic material present in bones is dispersed off by the heat and organic material which is not driven off is collected as activated carbon in the final product. It has a varying composition of tricalcium phosphate about 57-80%, calcium carbonate about 6-10% and carbon 7-10%.
We can regenerate the used bone charcoal by simply washing it with hot water followed by heating at about ${500^ \circ }C$ with a limited amount of air.

Note: Bone charcoal is used as a decolourizing agent and also as a deashing agent which helps in removal of inorganic impurities like sulphates, calcium and magnesium ions. It is also used as a black pigment in making prints, calligraphy and drawing inks.
Destructive distillation of wood results in tar, terpenes and methanol production along with methanol and destructive distillation of coal can result in production of about $700kg$ coal, coal tar and coal gas.