Extraction of The group 15 elements

 Mining of phosphate rock takes place on a vast scale (in 2001, 126Mt was mined worldwide), with the majority destined for the production of fertilizers and animal feed supplements. Elemental phosphorus is extracted from phosphate rock (which approximates in composition to Ca₃(PO₄)₂) by heating with sand and coke in an electric furnace (equation below); phosphorus vapour distils out and is condensed under water to yield white phosphorus.

    The principal source of As is FeAsS, and the element is extracted by heating (equation below) and condensing the As sublimate. An additional method is air-oxidation of arsenic sulfide ores to give As₂O₃ which is then reduced by C; As₂O₃ is also recovered on a large scale from flue dusts in Cu and Pb smelters.

     Antimony is obtained from stibnite by reduction using scrap iron (equation below) or by conversion to Sb₂O₃ followed by reduction with C.

   The extraction of Bi from its sulfide or oxide ores involves reduction with carbon (via the oxide when the ore is Bi₂S₃), but the metal is also obtained as a byproduct of Pb, Cu, Sn, Ag and Au refining processes.