Thermodynamics of TiOx in blast furnace-type slags
Thermodynamics of TiOx in blast furnace-type slags
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DOI：
10.1007/s11663-999-0004-y
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发表时间：
1999-02
期刊：
影响因子：
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通讯作者：
Y. Morizane;B. Ozturk;R. Fruehan
中科院分区：
文献类型：
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作者：
Y. Morizane;B. Ozturk;R. Fruehan
在1773K下进行了CaO-SiO_2-10%MgO-Al_2O_3-TiO_(1.5)-TiO_2渣、碳饱和铁和一氧化碳气氛之间的平衡研究，以确定渣中TiO_(1.5)和TiO_2的活度。这些热力学参数对于预测高炉内碳氮化钛的生成是必需的。为了计算氧化钛的活度，通过测量钛在碳化钛平衡状态下钛在碳饱和铁中的溶解度，确定了钛在碳饱和铁-碳-钛合金中的活度系数。1773K时，钛在铁液中的溶解度为1.3%，活度系数为0.023，相对于纯钛的活度系数为0.0013。在所研究的浓度范围内，二氧化钛含量对其活度系数的影响很小。在所研究的CaO含量为35%~50%、SiO_2含量为25%~45%、Al_2O_3含量为7%~22%、MgO含量为10%的渣系中，相对于纯固体标准态，TiO1.5和TiO2的活度系数分别为2.3~8.8和0.1~0.3。利用得到的热力学数据，对碳氮化钛的生成进行了预测。假定“TiO2值”，即渣中的总钛以TiO2值表示，并利用测得的TiO1.5和TiO2活度系数的值，计算了钛在高炉型渣和碳饱和铁间的平衡分配。[%钛]/(%‘二氧化钛’)的值在0.1到0.2之间。
Equilibrium studies between CaO-SiO2-10 pct MgO-Al2O3-TiO1.5-TiO2slags, carbon-saturated iron, and a carbon monoxide atmosphere were performed at 1773 K to determine the activities of TiO1.5and TiO2in the slag. These thermodynamic parameters are required to predict the formation of titanium carbonitride in the blast furnace. In order to calculate the activity of titanium oxide, the activity coefficient of titanium in carbon-saturated iron-carbon-titanium alloys was determined by measuring the solubility of titanium in carbon-saturated iron in equilibrium with titanium carbide. The solubility and the activity coefficient of titanium obtained were 1.3 pct and 0.023 relative to 1 wt pct titanium in liquid iron or 0.0013 relative to pure solid titanium at 1773 K, respectively. Over the concentration range studied, the effect of the TiOxcontent on its activity coefficient is small. In the slag system studied containing 35 to 50 pct CaO, 25 to 45 pct SiO2, 7 to 22 pct Al2O3, and 10 pct MgO, the activity coefficients of TiO1.5and TiO2relative to pure solid standard states range from 2.3 to 8.8 and from 0.1 to 0.3, respectively. Using thermodynamic data obtained, the prediction of the formation of titanium carbonitride was made. Assuming hypothetical ‘TiO2,’i.e., total titanium in the slag expressed as TiO2, and using the values of the activity coefficients of TiO1.5and TiO2determined, the equilibrium distribution of titanium between blast furnace-type slags and carbon-saturated iron was computed. The value of [pct Ti]/(pct ‘TiO2’) ranges from 0.1 to 0.2.