Solubilities of Colemanite, Ulexite, Pandermite And Tunellite Minerals in Different Alkaline Solutions

Abstract

In this vvork solubilities of four boron minerals and their cal- cination products in alkaline Solutions are investigated. The solubility expcriments have been made with NaOH3, NH:), Na2CO3 and (Na2CO3 + NaHCO3) Solutions of : 0.5, 2.0 and 5.0 normalities and as well as at room (20° -30O and as at higher (80' - 90°C) temperatures. The solubility ratios of the minerals in NaOH Solutions do increase with the increase of concentrations and temperature. It has been obser- ved that Tunellite mineral dissolves completely in hot NaOH solution. The solubility ratios in ammonia Solutions are indirectly proportional with the concentration and directly porportional with the temperature except for Tunellite mineral. The four minerals and their calcination products are almost completely soluble in hot Na2CO3 solution as well as in hot (Na2C03 + NaHC03) solution. In order to dissolve the four minerals in Na2CO3 and (Na2CO3-|-NaHCO3) Solutions at room temperature, it is neccssary to make them calcined. The temperature ranges of calcination are; for Colemanite 300 - 350 C, for Ulexite 150 C, for Pandermite 450'C and for Tunellite 250J - 300°C.