Local strucuture analysis of Cr(VI) ion dispersed in compound phases of Cr-containing slag

2016 Fiscal Year Final Research Report

• Project/Area Number: 26420755
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Metal making/Resorce production engineering
• Research Institution: Osaka University
• Principal Investigator: Masanori Suzuki 大阪大学, 工学研究科, 講師 (20610728)
• Co-Investigator(Renkei-kenkyūsha): MIZOGUCHI Teruyasu 東京大学, 生産技術研究所, 准教授 (70422334)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 六価クロム / X線吸収微細構造 / 第一原理計算

Outline of Final Research Achievements

To clarify the formation mechanism of Cr(VI) ion in Cr-containing slag, we investigated local structure of Cr ion dispersed in dicalcium silicate (2CaO.SiO2), Merwinite (3CaO.MgO.2SiO2) and Melilite (2CaO.Al2O3.SiO2), which are recognized as main compound phases composing Cr-containing slag. Our study including X-ray absorption analyses of these Cr-bearing compounds and first-principle simulations revealed that, (1) high-valence Cr ions including Cr(VI) are dispersed in dicalcium silicate when annealed in air atmosphere, (2) although Merwinite accepts Cr ion dispersion mainly as Cr(III), small amount of high-valence Cr ions are also detected, (3) Melilite accepts Cr ion dispersion only as Cr(III) if annealed in air atmosphere.

Free Research Field

熱力学、高温物理化学、界面制御工学