Home – Home – Jornals – Chemistry for Sustainable Development 2008 number 5

It is shown that the main hindrance for the use of phosphohemihydrate, obtained during sulphuric treatment of the Khibiny apatite concentrate, in the production of construction materials is an increased content of phosphorus admixture in water-insoluble form. According to the previously developed technology of sulphuric extraction of the concentrate of lanthanoids from phosphohemihydrate, one achieves efficient leaching of water-insoluble phosphorus which gets accumulated in leaching solutions during their repeated use. It is proposed to remove phosphorus from sulphuric solutions in the form of hydrated titanylphosphate by means of precipitation with titanyl sulphate. The possibility to recover titanyl sulphate with the help of the alkaline treatment of hydrated titanylphosphate is demonstrated; the resulting product is a component of detergent Na₃PO₄ · 12H₂O. The versions of the sulphuric technology of phosphohemihydrate treatment excluding the formation of liquid wastes that require utilization are considered.