【作者】 张春风；

【导师】 刘进荣； 刘启旺；

【作者基本信息】 内蒙古工业大学 ， 应用化学， 2007， 硕士

【摘要】 为实现液相生化法烟气脱硫的连续高效运行,本文对脱硫过程中Fe³⁺催化氧化与微生物代谢协同作用时的动力学规律进行探索,实验分别考察了过渡金属催化和微生物代谢动力学特征,在实验基础上对二者协同作用时的脱硫过程动力学规律进行了关联。文中从溶液酸度、Fe³⁺浓度、S（Ⅳ）浓度、温度等方面考察了Fe³⁺催化氧化S（Ⅳ）动力学规律,得到Fe³⁺催化氧化S（Ⅳ）过程中动力学控制步骤为Fe²⁺的氧化,且pH在0³范围内,氧化速率随着H+浓度的升高而降低;Fe³⁺浓度为0⁰.01 mol·L-1时,氧化速率随Fe³⁺浓度的增加而加快,继续增加Fe³⁺浓度,氧化速率没有明显变化;S（Ⅳ）浓度0⁰.1 mol·L-1时,氧化速率随S（Ⅳ）浓度的增加而加快。由实验数据关联得到了氧化速率公式。反应速率在20⁴0℃范围内随温度升高而加快,反应活化能约为13 kJ·mol-1。在实验基础上推测反应机理为自由基链反应机理。进一步确定了不同条件下氧化亚铁硫杆菌的生长动力学参数——比生长速率,得到DYB1对亚铁离子的氧化速率在接种量10%,Fe²⁺初始浓度为10 g/L,pH为2.5左右,30℃下摇床恒温培养,转速150 r/min时为0.42 g/（L·h-1）。脱硫实验表明,液相生化法脱硫中脱硫过程主要受化学反应控制,Fe³⁺浓度是整个反应的关键因素。该系列反应的速率控制步骤为Fe³⁺催化氧化溶液中生成的S（Ⅳ）,自身被还原为Fe²⁺。氧化亚铁硫杆菌不直接参与脱硫,而通过氧化Fe²⁺为Fe³⁺对反应速率产生影响,这种影响可用Fe³⁺浓度与氧化亚铁硫杆菌浓度变化引起的速率常数之间的关系来表达。更多还原

【Abstract】 The kinetics of the coordination interaction of Fe³⁺ catalyzed oxidation and microorganism metabolize were studied in order to achieve the kinetics of wet biochemical flue gas desulfurization technology, the kinetics equation of kinetic determination was correlated between Fe³⁺ catalyzed oxidation and microorganism metabolize with the experimental data.The effect of pH, concentration of Fe³⁺ and S（Ⅳ） and temperature on the kinetics was presented in the present work. It was shown that the oxidation of Fe²⁺ was the rate-determining step in the process of Fe³⁺ catalyzed oxidation S（Ⅳ）,the oxidation rate of Fe²⁺ decreased with the increasing concentration of H+ when pH of the solution was within the range of 0³, the oxidation rate of Fe²⁺ increased with the increasing concentration of Fe³⁺ as the concentration of Fe³⁺ was within the range of 0⁰.01 mol·L-1 ,the oxidation rate did not change significantly with the further increasing of the concentration of Fe³⁺, the oxidation rate of Fe²⁺ increased with the increasing concentration of S（Ⅳ）as the concentration of S（Ⅳ）was within 0⁰.1 mol·L-1.The oxidation rate equation was correlated with the experimental data. The oxidation rate increased with the increasing temperature at 20⁴0℃, with the activation energy of 13kJ·mol-1. The reaction of Fe （Ⅲ） catalyzed oxidation S（Ⅳ） was controlled by the radical chain reaction mechanism.The upgrowth kinetics parameter-μof thiobacillus ferrooxidans bacteria （DYB1） was achieved under different conditions. The oxidation rate of （DYB1） for Fe²⁺ was determined by means of experimentals. To speak more specifically, the oxidation rate reached 0.42g/（ L·h-1） under the circumstance of the inoculation 10%, initial concentration of Fe²⁺ 10g/L, pH 2.5,30℃for rotational culture and agitation speed 150r/min.The experiment data of desulfurization indicated that desulfurization process was controlled by chemical reaction in the wet biochemical flue gas desulfurization, in which the concentration of Fe³⁺ was the key factor. The reaction product S（Ⅳ） itself reducing in Fe³⁺ catalyzed oxidation solution was the rate-determining step in the process of desulfurization.The thiobacillus ferrooxidans bacteria did not participate in desulfurization process, but it can bring farther influence on transition oxidation Fe²⁺ to Fe³⁺ for the process. The influence was expressed by the rate constant which was correlated with concentration of Fe³⁺ and the amount of thiobacillus ferrooxidans bacteria.更多还原