Spinel phase is considered to be the optimal phase for stabilization of chromium in stainless steel slag.In order to restrain chromium leaching from slag for the effective environmental protection,Al2O3 was utilized f...Spinel phase is considered to be the optimal phase for stabilization of chromium in stainless steel slag.In order to restrain chromium leaching from slag for the effective environmental protection,Al2O3 was utilized for the modification treatment,and the effects on the enrichment and stabilization of chromium were investigated. The mineral phases and the existence state of chromium in slag with various Al2O3 contents at different basicities（ w（CaO）/w（SiO2） were analyzed by scanning electron microscopy-energy dispersive spectroscopy（ SEM-EDS） and X-ray diffraction（ XRD）. The results showed that chromium mainly existed in the glass and spinel phases at basicity of 1. 0 and 1. 5. As the slag basicity increased to 2. 0,chromium was also found in periclase phase. Al2O3 in the stainless steel slag reacted with MgO and Cr2O3,which could generate the Al-rich Mg（CrxAl（1- x））2O4 solid solution. Moreover,the addition of Al2O3 was favorable to reduce the solubility of chromium oxide in liquid phase and suppress the precipitation of periclase phase. The experimental results demonstrated that Al2O3 modification has a positive influence on the enrichment and the stabilization of chromium in the stainless steel slag.展开更多
Glass-ceramics have been prepared by using stainless steel slag, fly ash and coal fly ash that were figobtained from industrial solid waste. The crystallization behavior and mechanical characterization of the glass-ce...Glass-ceramics have been prepared by using stainless steel slag, fly ash and coal fly ash that were figobtained from industrial solid waste. The crystallization behavior and mechanical characterization of the glass-ce-ramics with different （CaO ＋ MgO）/（SiO2 ＋ Al2O3） content ratios were studied. While the basicity decreases from 1.2 to 0.9 cm^-3, the bridge oxygen content increases from 1.18 ~ 10^21 to 1.34 ~ 10^21 cm^-3. According to the deconvolution of Raman spectra, the relative abundance of the stretching of Si-Onb bond （Q^n units） can be obtained. The increase in the Q^3 units dominates the polymerization in the process of decreasing basicity. This change in bonding is demonstrated to lead to polymerization of the glass network and the increase in crystallization activation energy from 336.0 to 360.7 kJ·mol^-l. The results demonstrate that the production of the glass-ceramics from industrial steel slag, fly ash and coal fly ash is cost-effective and offers advantages over other production methods.展开更多
基金financial support by the National Natural Science Foundation of China(Project No.51374059 and 51304042)
文摘Spinel phase is considered to be the optimal phase for stabilization of chromium in stainless steel slag.In order to restrain chromium leaching from slag for the effective environmental protection,Al2O3 was utilized for the modification treatment,and the effects on the enrichment and stabilization of chromium were investigated. The mineral phases and the existence state of chromium in slag with various Al2O3 contents at different basicities（ w（CaO）/w（SiO2） were analyzed by scanning electron microscopy-energy dispersive spectroscopy（ SEM-EDS） and X-ray diffraction（ XRD）. The results showed that chromium mainly existed in the glass and spinel phases at basicity of 1. 0 and 1. 5. As the slag basicity increased to 2. 0,chromium was also found in periclase phase. Al2O3 in the stainless steel slag reacted with MgO and Cr2O3,which could generate the Al-rich Mg（CrxAl（1- x））2O4 solid solution. Moreover,the addition of Al2O3 was favorable to reduce the solubility of chromium oxide in liquid phase and suppress the precipitation of periclase phase. The experimental results demonstrated that Al2O3 modification has a positive influence on the enrichment and the stabilization of chromium in the stainless steel slag.
基金financially supported by the National Natural Science Foundation of China (Nos. U1360202, 51472030,51672024 and 51502014)Fundamental Research Funds for the Central Universities (No. FRF-TP-16-027A3)Innovation Project of Yunnan Province New Material Preparation and Processing Key Laboratory (No. 2016cx05)
文摘Glass-ceramics have been prepared by using stainless steel slag, fly ash and coal fly ash that were figobtained from industrial solid waste. The crystallization behavior and mechanical characterization of the glass-ce-ramics with different （CaO ＋ MgO）/（SiO2 ＋ Al2O3） content ratios were studied. While the basicity decreases from 1.2 to 0.9 cm^-3, the bridge oxygen content increases from 1.18 ~ 10^21 to 1.34 ~ 10^21 cm^-3. According to the deconvolution of Raman spectra, the relative abundance of the stretching of Si-Onb bond （Q^n units） can be obtained. The increase in the Q^3 units dominates the polymerization in the process of decreasing basicity. This change in bonding is demonstrated to lead to polymerization of the glass network and the increase in crystallization activation energy from 336.0 to 360.7 kJ·mol^-l. The results demonstrate that the production of the glass-ceramics from industrial steel slag, fly ash and coal fly ash is cost-effective and offers advantages over other production methods.
