LiO2对CaO—SiO2—MgO—Fe2O3—MnO2—P2O5精炼渣系脱磷的影响

在LiO2替代CaO-SiO2-MgO-Fe2O3-MnO2-P2O5精炼渣系中部分CaO的条件下，研究了LiO2含量、碱度及氧化性对钢液磷含量的影响。结果表明，在LiO2=15%,碱度（CaO LiO2)SiO2为2.0-2.5(Fe2O3 MnO2)为7%的条件下，该渣系对钢液的脱磷率在70%以上，控制钢液磷含量在0.009%以下。     

氟对CaO—CaF2—SiO2和CaO—CaF2—SiO2—FeOx玻璃硅酸盐网络体的影响

通过使用X射线光电子分光仪(XPS)和穆斯堡尔分光检测仪对CaO-SiO2-CaF2和CaO-SiO2-CaF2-FeOx两种玻璃质进行了检测，研究F的化学性能和加入F后对硅酸盐网络体聚合度的影响。Fls XPS衍射图表明，F易与C8结合而不是Si，从CaO-SiO2-CaF2玻璃体的Ols XPS衍射图和CaO-SiO2-CaF2-FeOx玻璃体的穆斯堡尔衍射图的Fe^2 与Fe^3 的比值分析表明，加入CaF2对两种玻璃硅酸盐网络体没有解聚作用。     

CaO—SiO2—Na2O—CaF2—Al2O3—MgO保护渣系的Al2O3吸收速率和粘度

采用CaO-SiO2-Na2O-CaF2-Al2O3-MgO渣系,通过测定熔渣的粘度和Al2O3吸收速率,研究连铸保护渣的Al2O3吸收速率与粘度及化学成分之间的关系。在一定条件下,当CaO/SiO2为1.2左右时,粘度达到最小值,Al2O3吸收速率达到最大值,分别为0.10?Pa*s、8.403×10-4?kg*m-2*s-1。随着渣中Na2CO3含量、CaF2含量和MgO含量的增加,粘度减小,Al2O3吸收速率增大。随着渣中Al2O3含量的增加,粘度增大,Al2O3吸收速率减小。粘度为Al2O3吸收速率的主要控制因素。随着熔渣粘度的增加,连铸保护渣的Al2O3吸收速率逐渐减小。     

BaO—CaO—Na2O—CaF2—Cr2O3渣系的不锈钢脱磷

测定了１５００℃时磷在ＢａＯ－ＣａＯ－Ｎａ２Ｏ－ＣａＦ２－Ｃｒ２Ｏ３渣子和０．１２Ｃ－０．７１Ｓｉ－１８Ｃｒ不锈钢熔体之间的分配比，试验结果表明，该渣系的不锈钢脱磷能力比ＣａＯ基渣好，与ＢａＯ基渣相当。     

共沉淀—煅烧法制备CeO2—Y2O3—ZrO2陶瓷粉末

采用共沉淀－煅烧法制备了ＣｅＯ２－Ｙ２Ｏ３－ＺｒＯ２（ＣＹＺ）三元复合氧化物陶瓷粉末，所制备的ＣＹＺ粉末为稳定的四方相结构，在高于１４００℃的温度下煅烧，其流动性大为改善，可用于等离子喷涂。     

Cao—SiO2—CaF2—Na2O四元渣系的挥发

通过回归正交设计确定了连铸保护渣基料挥发率同温度、Ｎａ２ＣＯ３含量、ＣａＦ２含量、减度及时间的二次函数关系式。分析结果表明，温度对挥发率的影响随着Ｎａ２ＣＯ３含量的增加而增加；碱度Ｒ为０．９时挥发率最大；Ｎａ２ＣＯ３对挥发率的影响略高于ＣａＦ２。     

Cao—SiO2—CaF2—FeO—Na2O渣系铁水脱磷,脱硫预处理

本次研究了含２０％，ＣａＦ２，ＣａＯ／ＳｉＯ２＝４的ＣａＯ－ＳｉＯ２－ＣａＦ２８渣系脱磷和脱硫的能力，同时也确定了该脱硅量。本研究过程中用ＦｅＯ（４－８％）和Ｎａ２Ｏ（１－６％）来改变铁水的氧化势。试验是在１０ｋｇ敞口感应电上进行的，炉子为ＡＩ２Ｏ３耐火材料，温度为１３５０－１４００℃。试验过程中用伽伐尼电池连续测定铁水的氧化势，共范围为１０＾１３。４ａｔｍ（试验前）至１０＾１２．０ａｔｍ（试验后     

硫酸铵—1—（2—吡啶偶氮）—2—萘酚—磺酸—Tween80体系萃取分离铁

研究了硫酸铵－１－（－２－吡啶偶氮）－２－萘酚－Ｔｗｅｅｎ８０体系萃取铁的行为。试验表明,当溶液ＰＨ２．０～４．０能使Ｆｅ（Ⅱ）与Ｚｎ（Ⅱ）与Ｚｎ（Ⅱ）,Ｃｄ（Ⅱ）、Ｍｎ（Ⅱ）、Ｍｇ（Ⅱ）、Ａ（Ⅲ）定量分离。应用该计测定了铝铪合金中Ｆｅ的含量,结果满意。     

1—（—2—吡啶偶氮）—2—萘酚修饰碳糊电极测定铜的研究

本文报告１－（２－吡啶偶氮）－２－萘酚（ＰＡＮ）修饰碳糊电极在乙酸盐缓冲液（ｐＨ５．０）中，与铜离子生成电活性螯合物，并吸收在电极表面，经介质交换到０．１ｍｏ１／ＬＫＣ１中，用微分脉冲伏安法测定，用－０．１５Ｖ出现一灵敏的还原峰。用正交试验优化法研究了测定铜的最佳条件。其相对标准偏差３．２７％。这一方法用于阳极泥中铜的测定，回收率为９４．３％。还用双电位阶跃计时仑法，循环伏安法研究了ＰＡＮ修饰碳糊     

氮在Ca-SiO_2-Al_2O_3渣中的热力学研究

本文借助于光学碱度概念,对CaO-SiO_2-Al_2O_3熔渣中氮的稳定性进行了研究。结果表明,气相中氮不是与渣中自由氧离子作用,而是与网络结构作用而进入熔渣。根据氮与网络结构SiO_2或Al_2O_3之间的反应。提出了熔渣氮容量的新定义。根据渣中氮的行为,结合一系列的试验结果,得到了1823 K时CaO-SiO_2-Al_2O_3渣的氮容量计算公式IgC_N=-11.721gA-14.26和三元渣系的等氮容量曲线。     

Accurate Density Calculation for Molten Slags in SiO2-Al2O3-CaO-MgO-‘FeO’-‘Fe2O3’ Systems

Metallurgical and Materials Transactions B - A simple and accurate density calculation model for molten slags containing iron oxides in SiO2-Al2O3-CaO-MgO-‘FeO’-‘Fe2O3’...     

二元碱度和Al_2O_3对CaO-SiO_2-FeO-Fe_2O_3-P_2O_5-Al_2O_3-MgO-MnO钢渣中磷酸盐富集的影响

以八元CaO-SiO_2-FeO-Fe_2O_3-P_2O_5-Al_2O_3-MgO-MnO钢渣体系为研究对象,结合热力学计算和实验检测,分析了二元碱度B和Al_2O_3含量对八元钢渣系中磷酸盐富集行为的影响。结果表明:钢渣二元碱度和Al_2O_3含量直接影响钢渣中f-C2S的生成量,进而影响磷酸盐富集相nC_2S-C_3P内P_2O_5的含量。随着二元碱度从1.3提高至2.5,磷酸盐富集率增大,磷酸盐富集相nC2S-C3P中的P_2O_5含量呈现先迅速增大(B从1.3至1.7),然后逐渐减小(B从1.8至2.5)的趋势。当二元碱度和Al_2O_3质量分数分别控制在1.7和12%时,即当满足四元碱度R为1.23时,此八元钢渣体系有较好的磷酸盐富集效果,磷酸盐富集相nC_2S-C_3P内的P_2O_5的质量分数可以达到24.23%。     

熔渣中BaO和TiO2对钢液氮含量的影响

 为了研究熔渣中BaO和TiO2含量对钢液氮含量的影响,选用CaO SiO2 Al2O3系碱性渣作为基本成分,在此基础上添加BaO和TiO2,观察它们对钢液氮含量的影响。结果表明：在渣中添加BaO和TiO2可促进钢液脱氮,且钢液中氮含量随渣中BaO和TiO2含量的增加呈线性下降。     

等离子喷涂Al2O3涂层CO2连续激光反射性能的研究

采用等离子喷涂法制备了Al2O3涂层,研究了相结构对CO2连续激光反射率的影响。结果表明,Al2O3涂层中的主相为γ-Al2O3,涂层对CO2连续激光的反射率为23.65%±0.80%。γ-Al2O3的激光反射率高于α-Al2O3,主要原因是α-Al2O3和γ-Al2O3的晶体结构不同,在与激光相互作用时,由于γ-Al2O3存在电子轨道交叠,电子带间跃迁能力较强,提高了其对CO2连续激光的反射率。等离子喷涂Al2O3涂层在激光辐照过程中存在γ-Al2O3到α-Al2O3的相变,使得涂层的反射率下降。     

CaO－SiO_2－Al_2O_3－MgO渣系的作用浓度模型及其应用

应用炉渣的共存理论建立了ＣａＯ－ＳｉＯ２－Ａｌ２Ｏ３－ＭｇＯ四元系的作用浓度模型，将大冶钢厂和上钢五厂以及日本山阳钢厂、的轴承钢精炼渣系代入模型进行计算。选取了对钢水的纯净度有直接影响的结构单元的作用浓度对三者的脱氧、脱硫能力以及钢中点状夹杂物形成趋势进行了分析。计算结果说明，大冶的精炼渣系点状夹杂物形成趋势小，而山阳的精炼渣系具有较强的脱硫和脱氧能力。分析结果与检验结果一致。     

CaO-SiO2-MgO-Al2O3-Cr2O3渣系黏度结构分析及Iida模型应用

 为了实现冶炼铬铁合金过程中含铬渣系黏度的精准控制,从微观结构方面研究了碱度及Cr2O3质量分数变化对铬铁冶炼渣系黏度的影响并优化了Iida黏度预测模型。通过转筒法测量CaO-SiO2-MgO-Al2O3-Cr2O3渣系黏度,结合拉曼光谱从熔渣微观结构方面阐述了Cr2O3质量分数及碱度变化对CaO-SiO2-MgO-Al2O3-Cr2O3渣系黏度的影响。结果表明,熔渣黏度与其表征聚合度的BO参数值均随Cr2O3质量分数的增加而升高,随二元碱度值的增大而降低,熔渣黏度与渣系聚合度变化趋势相一致。根据测量得到的含Cr2O3熔渣黏度数据,进一步优化了Iida黏度预测模型。经过优化后的模型计算黏度值与实际测值吻合较好,利用Iida黏度模型可在较大的温度与成分范围内进行含铬渣黏度的预测。     

The nitrogen reaction between carbon saturated Iron and Na2O-SiO2 Slag: Part 1. Thermodynamics

The nitrogen partition ratio between Na₂O-SiO₂ slags and carbon saturated iron was measured for slags containing from 0.4 to 0.55 mole fraction of Na₂O and the temperature range 1200° to 1350 °C. The nitrogen is dissolved in the slag as the cyanide ion (CN⁻) and the partition ratio is proportional to the oxygen pressure to the −1/4 power as predicted for CN⁻ dissolution. The oxygen pressure for carbon saturated iron silicon alloys is controlled by the Si (metal)-SiO₂ (slag) equilibrium. The nitrogen partition ratio and the cyanide capacity increase with Na₂O content and temperature. Calculations indicate that Na₂O-SiO₂ slags will absorb three times more nitrogen than CaO-Al₂O₃ slags at the same basicity and temperature. Based on thermodynamic calculations it is estimated that for a typical Na₂CO₃ hot metal treatment, half of the nitrogen in the metal could possibly be removed. F.Tsukihashi is on leave of absense from Department of Metallurgical Engineering and Materials Science, Faculty of Engineering, The University of Tokyo, Bunkyo, Tokyo 113, Japan     

Catalytic Incineration of Acrylonitrile with Platinum Supported on Al2O3

The catalytic decomposition of acrylonitrile with catalysts was investigated in a bench scale fixed bed reactor in this study. Two catalysts, including Pt/γ-Al2O3 and Cr2O3/α-Al2O3, were tested to study their catalytic activity in the complete oxidation of acrylonitrile. The results show that the Pt/γ-Al2O3 catalyst has better performance. The operating parameters such as operating temperature, acrylonitrile concentration, space velocity, and oxygen concentration were conducted in a series of experiments on the Pt/γ-Al2O3 catalyst. The results indicate that decomposition efficiency increases with temperature and oxygen concentration and decreases with the increases of space velocity and acrylonitrile concentration. With a regression model, the operating temperature is the most effective parameter on the decomposition of acrylonitrile. Carbon dioxide is the dominant product and carbon monoxide is an insignificant product of the decomposition of acrylonitrile. Material balance on carbon is good for the experiments. According to the BET and elemental analyzer analysis, major factors that cause the deactivation effect may result from nitrogen poisoning and carbon masking on the catalyst surface, especially at lower temperatures.     

Recycling of High Ferrous Bauxite Reducing Slag for Synthesis of CaAl2 Si2 O8-Al2 O3-CaAl12 O19 Composite

CaAl_2 Si_2 O_8-Al_2O_3-CaAl_(12) O_(19)( CAS_2-Al_2O_3-CA_6) composite was synthesized through reaction sintering alumina and bauxite reducing slag.The CAS_2-Al_2O_3-CA_6 composite was mainly composed of α-Al_2O_3,CAS_2,and CA_6.Gehlenite( Ca_2Al_2 SiO_7,C_2AS) phase was effectively transformed to CAS_2 and CA_6through high-temperature reaction sintering under weak oxidizing atmosphere at 1400 ℃ for 4h.SEM( scanning electron microscopy) and EDS( energy dispersive spectroscopy) analysis indicated that black and needle-shaped Al_2O_3,rhombic or irregular polygonal-shaped Fe Al_2O_4,and glassy phase Ca_2Al_2 SiO_7disappeared after the reaction sintering.The light gray and flaky hexagon crystals of Ca Al_(12)O_(19)(10μm) and the grainy particles of Al_2O_3( 2-7μm) were observed in the CAS_2-Al_2O_3-CA_6 composite.The gray crystals of CAS_2 act as the binding phase and are distributed around CA_6 and Al_2O_3.CAS_2-Al_2O_3-CA_6 composite exhibits high refractoriness and service temperature,which are 1650 ℃ and 1450 ℃,respectively.Reaction sintering of alumina and bauxite reducing slag is a feasible method for the synthesis of CAS_2-Al_2O_3-CA_6 composite.