【作者】 杨勇；

【导师】 华一新；

【作者基本信息】 昆明理工大学 ， 有色金属冶金， 2002， 硕士

【摘要】 本文在前期工作的基础上，主要探讨纯硫化锑、硫化铅、硫化锌、硫化亚铁一元系在水蒸气下的反应动力学规律。 经过合理的换算，实验气体的参考流量是1500ml／min，基础温度为1023K，采用失重法来测量物质的失重速率。 首先进行了硫化锑在氩气下的挥发实验研究，建立了相应的热力学数学模型，求出硫化锑在氩气中的表观挥发活化能为55.54kJ／mol。实验结果证明：提高温度和增大氩气流量都能加快硫化锑的挥发速率；硫化锑在氩气中的扩散主要由气相传输控制；当温度升高时，气相传质系数却随之降低。 而硫化锑在水蒸气下的挥发过程和在氩气中并不相同。在熔体表面，硫化锑会被水蒸气氧化成氧化锑，然后硫化锑和氧化锑一起在气相主体中挥发，并会发生交互反应生成微量的金属铅。硫化锑在水蒸气下的挥发速率要大于在氩气中的挥发速率。水蒸气主要有以下作用：使熔体表面部分硫化锑发生氧化，并使气相主体中的硫化锑也部分氧化，减少了气相中硫化锑的分压；另外，硫化锑在水蒸气中的扩散系数也较氩气中的大。经过分析，硫化锑在水蒸气里的挥发仍由气相传输控制。 硫化铅在水蒸气里的失重情况比较特殊，在973K和1023K时，硫化铅初始出现增重现象，经过X-衍射分析，发现有中间物质nPbO·pbSO₄生成，硫化铅的增重主要由化学反应引起；而在1073K以上时，硫化铅在水蒸气中失重的主要原因是自身的挥发。 硫化锌在水蒸气下的失重主要是化学反应所引起，并求出表观反应活化能E=49.5kJ／mol。而硫化亚铁在水蒸气下的焙烧反应非常的复杂，经过X-衍射分析，在焙烧产物中含有Fe_1-xS、FeS、FeS₂、Fe₂O₃和Fe₃O₄等多种成分，同时指出硫化亚铁在水蒸气下增重主要受化学反应的影响。更多还原

【Abstract】 On the basis of previous work, the reaction kinetics of antimony trisulfide ?lead trisulfide s zinc trisulfide and ferric trisulfide in argons water vapor and gas was studied with thermogravimetry at temperature range from 973K to 1173K. The gas flow-rate adopted was 1500ml/min.The investigation of antimony trisulfide was made in argon and water vapor. A theoretical model was developed to calculate the overall rate constant and the mass transfer coefficient in gas phase. The experimental results show that the vaporization rate is enhanced with increasing temperature and gas flow-rate. The apparent activation energy for the process is found to be 55.54 kJ/mol. It is demonstrated that the mass transfer coefficient in gas phase is decreased with increasing temperature.The evaporation mechanism of antimony trisulfide in water vapor is different from that in argon. Some antimony trisulfide vaporize solely and theother antimony trisulfide is oxidized to antimony oxide by water vapor. The reaction between antimony trisulfide and antimony oxide produce antimony in the gas phase. The advantages of water vapor will be discussed. The partial pressure of gaseous antimony trisulfide in bulk gas is fall while it is oxidized by vapor. The diffusion coefficient of antimony trisulfide in water vapor is bigger than that in argon. The melt surface temperature in water vapor is higher than that of argon because the values of heat transfer coefficient and thermal capacity of water vapor is bigger. Data from experimental prove that the evaporation rate is mainly controlled by mass transport in the gas phase whether in argon or in water vapor.The weight loss of lead sulfide in water vapor is exceptional. It is shown that the weight-time curves display an ascending result at temperature of 973K and 1023K. XRD analysis shows that nPbO .PbSO4 is produced. The chemical reaction leads to the weight increase. But the chief reason of weight loss is the evaporation of lead trisulfide at the top of 1073K.zinc sulfide is oxidized by water vapor that causes weight loss. The apparent reaction activation energy for the process has a value of 49.5 kJ/mol in the temperature range investigated.The roasting reaction of ferric sulfide in water vapor is very complex. XRD analysis indicates that the products contain Fe1-xS FeS FeS2 Fe2O3 and Fe3O4. The analysis indicates that the chemical kinetic aspects appear to affect the weight loss.更多还原