Effects of iron oxide on crystallization behavior and spatial distribution of spinel in stainless steel slag

Abstract

Chromium plays a vital role in stainless steel due to its ability to improve the corrosion resistance of the latter. However, the release of chromium from stainless steel slag (SSS) during SSS stockpiling causes detrimental environmental issues. To prevent chromium pollution, the effects of iron oxide on crystallization behavior and spatial distribution of spinel were investigated in this work. The results revealed that FeO was more conducive to the growth of spinels compared with Fe₂O₃ and Fe₃O₄. Spinels were found to be mainly distributed at the top and bottom of slag. The amount of spinel phase at the bottom decreased with the increasing FeO content, while that at the top increased. The average particle size of spinel in the slag with 18wt% FeO content was 12.8 µm. Meanwhile, no notable structural changes were observed with a further increase in FeO content. In other words, the spatial distribution of spinel changed when the content of iron oxide varied in the range of 8wt% to 18wt%. Finally, less spinel was found at the bottom of slag with a FeO content of 23wt%.

Keywords

stainless steel slag / spinel / chromium / waste remediation / ferrous oxide

References

[1] Q. Zhao, C.J. Liu, X.H. Mei, H. Saxén, and R. Zevenhoven, Research progress of steel slag-based carbon sequestration, Fundam. Res., 2022. https://doi.org/10.1016/j.fmre.2022.09.023

[2] Xiong J, Tong YL, Peng JL, Zhang SH. Strength–toughness improvement of 13Cr4NiMo martensitic stainless steel with thermal cyclic heat treatment. J. Iron Steel Res. Int., 2023, 30(8): 1499.

[3] Wang CQ, Li J, Yang H, Li CR. Feasibility analysis of industrial waste acid treatment of stainless steel smelting slag. Mod. Metall., 2010, 38(1): 1.

[4] Zhang X, Zhang M, Guo M. Advances and trends in high-temperature modification-crystallization control detoxification of stainless steel slag. Chin. J. Eng., 2023, 45(4): 577.

[5] L.H. Cao, C.J. Liu, Q. Zhao, and M.F. Jiang, Analysis on the stability of chromium in mineral phases in stainless steel slag, Metall. Res. Technol., 115(2018), No. 1, art. No. 114.

[6] Li YM, Zhao Q, Mei XH, Liu CJ, Saxén H, Zevenhoven R. Effect of Ca/Mg molar ratio on the calcium-based sorbents. Int. J. Miner. Metall. Mater., 2023, 30(11): 2182.

[7] Pillay K, von Blottnitz H, Petersen J. Ageing of chromium(III)-bearing slag and its relation to the atmospheric oxidation of solid chromium(III)-oxide in the presence of calcium oxide. Chemosphere, 2003, 52(10): 1771.

[8] Li WL, Xue XX. Effect of cooling regime on phase transformation and chromium enrichment in stainless-steel slag. Ironmaking Steelmaking, 2019, 46(7): 642.

[9] Zhao Q, Liu K, Sun LF, et al. Towards carbon sequestration using stainless steel slag via phase modification and co-extraction of calcium and magnesium. Process. Saf. Environ. Prot., 2020, 133, 73.

[10] Mou QQ, Li JL, Zeng Q, Zhu HY. Effect of Fe₂O₃ on the size and components of spinel crystals in the CaO-SiO₂-MgO-Al₂O₃-Cr₂O₃ system. Int. J. Miner. Metall. Mater., 2019, 26(9): 1113.

[11] Shen HT, Forssberg E. An overview of recovery of metals from slags. Waste Manage., 2003, 23(10): 933.

[12] F. Kukurugya, P. Nielsen, and L. Horckmans, Up-concentration of chromium in stainless steel slag and ferrochromium slags by magnetic and gravity separation, Minerals, 10(2020), No. 10, art. No. 906.

[13] Tossavainen M, Engstrom F, Yang Q, et al. Characteristics of steel slag under different cooling conditions. Waste Manage., 2007, 27(10): 1335.

[14] Engström F, Adolfsson D, Yang Q, Samuelsson C, Björkman B. Crystallization behaviour of some steelmaking slags. Steel Res. Int., 2010, 81(5): 362.

[15] Wang ZJ, Sohn I. Understanding the solidification and leaching behavior of synthesized Cr-containing stainless steel slags with varying Al₂O₃/SiO₂ mass ratios. Ceram. Int., 2021, 47(8): 10918.

[16] Wang ZJ, Sohn I. Immobilizing chromium in stainless steel slags with MnO addition. J. Am. Ceram. Soc., 2021, 104(2): 697.

[17] Zhang YM, Yi LY, Wang LN, et al. A novel process for the recovery of iron, titanium, and vanadium from vanadium-bearing titanomagnetite: Sodium modification–direct reduction coupled process. Int. J. Miner. Metall. Mater., 2017, 24(5): 504.

[18] Das SK. Quantitative mineralogical characterization of chrome ore beneficiation plant tailing and its beneficiated products. Int. J. Miner. Metall. Mater., 2015, 22(4): 335.

[19] Zhao Q, Li JY, You KW, Liu CJ. Recovery of calcium and magnesium bearing phases from iron–and steelmaking slag for CO₂ sequestration. Process. Saf. Environ. Prot., 2020, 135, 81.

[20] Cao LH, Liu CJ, Zhao Q, Jiang MF. Effect of Al₂O₃ modification on enrichment and stabilization of chromium in stainless steel slag. J. Iron Steel Res. Int., 2017, 24(3): 258.

[21] Holappa L, Kekkonen M, Jokilaakso A, Koskinen J. A review of circular economy prospects for stainless steelmaking slags. J. Sustain. Metall., 2021, 7(3): 806.

[22] Liu L, Hu ML, Bai CG, Lü XW, Xu YZ, Deng QY. Effect of cooling rate on the crystallization behavior of perovskite in high titanium-bearing blast furnace slag. Int. J. Miner. Metall. Mater., 2014, 21(11): 1052.

[23] Zhao Q, Liu CJ, Cao LH, et al. Shear-force based stainless steel slag modification for chromium immobilization. ISIJ Int., 2019, 59(3): 583.

[24] Wu XR, Dong XM, Wang RT, Lu HH, Cao FB, Shen XM. Crystallization behaviour of chromium in stainless steel slag: Effect of feo and basicity. J. Residuals Sci. Technol., 2016, 13(Suppl. 1): S57.

[25] Yu TX, Jiang T, Wen J, Sun HY, Li M, Peng Y. Effect of chemical composition on the element distribution, phase composition and calcification roasting process of vanadium slag. Int. J. Miner. Metall. Mater., 2022, 29(12): 2144.

[26] Zhang S, Zhang YL, Wu SW. Effects of ZnO, FeO and Fe₂O₃ on the spinel formation, microstructure and physico-chemical properties of augite-based glass ceramics. Int. J. Miner. Metall. Mater., 2023, 30(6): 1207.

[27] Zeng Q, Li JL, Mou QQ, Zhu HY, Xue ZL. Effect of FeO on spinel crystallization and chromium stability in stainless steel-making slag. JOM, 2019, 71(7): 2331.

[28] Wang ZJ, Sohn I. Selective elemental concentration during the solidification of stainless steel slags for increased Cr recovery with MnO addition. J. Am. Ceram. Soc., 2020, 103(10): 6012.

[29] Wang ZJ, Yang J, Pan DA, Liu B, Tian JJ, Zhang SG. Present state of stainless steel slag resources disposal technique. J. Iron Steel Res., 2015, 27(2): 1.

[30] Diao J, Xie B, Wang Y, Ji CQ. Mineralogical characterisation of vanadium slag under different treatment conditions. Ironmaking Steelmaking, 2009, 36(6): 476.

[31] Wu SW, Zhang YL, Zhang S. Chromium enrichment in different crystalline phases of Cr-containing slag under various basicities and equilibrium temperatures. J. Iron Steel Res. Int., 2022, 29(9): 1412.

[32] Lu X, Huang XL, Wei RF, et al. Novel method for improving iron recovery from electric arc furnace slag: On-site hot modification. J. Iron Steel Res. Int., 2022, 29(8): 1224.

[33] Q. Zhao, C.J. Liu, L.H. Cao, X. Zheng, and M.F. Jiang, Stability of chromium in stainless steel slag during cooling, Minerals, 8(2018), No. 10, art. No. 445.

[34] Nguyen TX, Patra J, Chang JK, Ting JM. High entropy spinel oxide nanoparticles for superior lithiation–delithiation performance. J. Mater. Chem. A, 2020, 8(36): 18963.

[35] Tian KH, Duan CQ, Ma Q, et al. High-entropy chemistry stabilizing spinel oxide (CoNiZnXMnLi)₃O₄ (X = Fe, Cr) for high-performance anode of Li-ion batteries. Rare Met., 2022, 41(4): 1265.

[36] Shang HF, Xia DG. Spinel LiMn₂O₄ integrated with coating and doping by Sn self-segregation. Int. J. Miner. Metall. Mater., 2022, 29(5): 909.

[37] Yuan F, Zhao Z, Zhang YL, Wu T. Effect of Al₂O₃ content on the viscosity and structure of CaO-SiO₂-Cr₂O₃-Al₂O₃ slags. Int. J. Miner. Metall. Mater., 2022, 29(8): 1522.

[38] Dong WS, Wang XK, Peng SY. Preparation properties and use in catalysis of spinels. J. Petrochem. Univ. Sinopec, 1996, 9(4): 10.

[39] Tang ZY, Feng JJ, Xu GX. Study on multiple doping of spinel LiMn₂O₄. Acta Chim. Sin., 2003, 61(8): 1316.

[40] Zhao Q, Liu CJ, Zhang B, Jiang MF, Qi J, Saxén H, Zevenhoven R. Study on extraction of iron from chromite. Steel Res. Int., 2015, 86(12): 1541.

[41] Huo YZ, Gu HZ, Huang A, et al. Characterization and mechanism of dissolution behavior of Al₂O₃/MgO oxides in molten slags. J. Iron Steel Res. Int., 2022, 29(11): 1711.

[42] Zhao Q, Liu CJ, Gao TC, Gao L, Saxén H, Zevenhoven R. Remediation of stainless steel slag with MnO for CO₂ mineralization. Process. Saf. Environ. Prot., 2019, 127, 1.

[43] Li JL, Xu AJ, He DF, Yang QX, Tian NY. Effect of FeO on the formation of spinel phases and chromium distribution in the CaO-SiO₂-MgO-Al₂O₃-Cr₂O₃ system. Int. J. Miner. Metall. Mater., 2013, 20(3): 253.