磷是鋼鐵製品中的有害不純物，因此，除磷是一必要的手段-磷是一重要的資源，但其礦源主要集中少數區域，經由長期的開採已面臨耗竭的危機。鋼鐵製程將可提供磷礦新的來源，並可經由轉爐石除磷技術，進一步提高轉爐石的再利用性，並可大幅降低轉爐石的產生量。目前已發展之磷分離與回收技術，主要有磁場分離、毛細作用、淋溶和碳熱還原等方法。本研究嘗試以淋溶法萃取轉爐碴中之磷，以硝酸淋溶法萃取轉爐碴中磷技術已初步驗證其可行性，隣萃取效率最高可達20.20wt.%，後續仍有相當改善空間。

Phosphorus (P) is a detrimental impurity in the iron and steel products and its removal is necessary for iron and steel making process. Phosphorus is, on the other hand, an important resource which the presently-known ore reserve is concentrated in limited regions and is having a crisis on resource depletion after long-term mining. Through P recovery technology, the steel making process could provide a new source of phosphorus, improve the utilization rate and significantly reduce the amount of steelmaking slag. Major phosphorus separation and recovery technologies currently in market include: magnetic separation, capillary action, leaching dissolution and carbothermic reduction. Our research is trying to extract P from steelmaking slag based on leaching method. Preliminary feasibility has been confirmed that nitric acid leaching method could be utilized to extract P from steel making slag. Maximum extraction efficiency reached up to 20.20 wt%. The results shown there is quite space for improvement in future works.