What are the steps of the electro-thermic process for the manufacture of phosphorus from its mineral ?
Electro-thermal Process : Mixture of calcium phosphate (from Bone ash) sand and coke is introduced into a closed electric furnace through hopper by screw conveyor. Electric furnace is an Iron tank lined inside with refractory brick.
Outlet pipe at upper part connected to condensing system.
Electric arc is struck between two carbon electrode to maintain temperature 1775 K. At High temperature calcium phosphate react with sand to form calcium silicate and P2O5. Latter is reduced by coke to give phosphorous and CO.
2Ca3(PO4) +6SiO2 ---> 6CaSiO3+P4O10 +10C ---->10CO +P4



