Synthesis of Zirconium Oxychloride and Zirconia Low TENORM by Zircon Sand from Landak West Kalimantan

Abstract

In order to enhance the added value of zircon minerals (ZrSiO4) derived from tailing gold mining in Mandor, Landak, West Kalimantan; the hydrometallurgical process is needed to obtain zirconium products such as zirconium Oxychloride (ZrOCl2.8H2O) and zirconia (ZrO2). Zirconium products that are sold must meet the requirement of Technologically Enhanced Naturally Occurring Radioactive Material (TENORM) or (ThO2 + U3O8) is below 500 ppm. The purpose of this research was to process zircon sand with TENORM content 1784 ppm to be ZrOCl2.8H2O and ZrO2 low TENORM. Zircon sand processing has been carried out through melting zircon sand with NaOH to bind Zr became Na2ZrO3 and Si as the impurities to become Na2SiO3, water leaching to separate Na2ZrO3 from Na2SiO3 and other impurities, acid leaching (HCl) to convert Na2ZrO3 to be zirconium oxychloride low Si (ZOC-1) then ZOC-1 to be zirconium sulfate base (ZBS), ZBS then being deposited to be ZrO(OH)2, ZrO(OH)2 converted to be zirconium oxychloride low TENORM (ZOC-2), ZOC-2 then being crystallized to be ZrOCl2.8H2O and calcinated to be zirconia. The results showed that zircon sand from Mandor, Landak, West Kalimantan could be synthesized into ZrOCl2.8H2O with NORM 1.2586 ppm and zirconia with NORM = 3.5511 ppm, both products have met the industrial-grade requirement.