【作者】 那娟娟；

【导师】 冉均国；

【作者基本信息】 四川大学 ， 材料学， 2006， 硕士

【摘要】 有机氯化物对环境和人类健康造成严重危害，其污染问题已成为急待解决的问题。本文系统研究了纳米铁粉对四氯化碳和四氯乙烯的脱氯降解行为。将CCl₄和C₂Cl₄的脱氯率作为考察指标；分别采用超声波与纳米铁粉协同作用和超声波、水浴摇床与纳米铁粉共同作用两种实验方案，选用离子选择电极法测定氯离子浓度，考察了降解液的初始pH值，纳米铁粉用量，反应温度，摇床转速，反应时间，反应物的初始浓度等因素对脱氯效果的影响；并确定了纳米铁粉对CCl₄和C₂Cl₄脱氯的最佳工艺。 采用草酸铁连续微波热解法制备了纳米级铁粉，并进行了粒度表征。颗粒粒径小，粒度分布均匀。 超声波与纳米铁粉协同降解四氯化碳的研究结果表明：纳米铁粉和超声波两者产生互相强化作用，大大提高了四氯化碳的脱氯效果；并且随纳米铁粉用量、降解液初始pH值以及CCl₄初始浓度的增加，四氯化碳的脱氯率逐渐降低。 选用L₂₅（5⁶）正交试验方案，研究了超声波、纳米铁粉与水浴摇床共同作用降解四氯化碳，得出了四氯化碳脱氯的最佳工艺条件：当四氯化碳初始浓度为20mg／L时，降解液初始pH值2.0，纳米铁粉2.0g／100ml，反应温度50℃，摇床转速200rpm，降解时间18h。在此工艺条件下，获得了99.5％的脱氯率。其中，降解液的初始pH值对四氯化碳的脱氯率有极显著的影响。 此外，分别研究了超声波与纳米铁粉协同和超声波、水浴摇床与纳米铁粉共同降解四氯乙烯。结果表明：随着降解液初始pH值的增加，四氯乙烯的脱氯率呈现先减小后增大的趋势；当降解液的初始pH值为7.0时，脱氯率最低。四氯乙烯的脱氯率随纳米铁粉用量的增加先增大后减小。随反应时间的延长、反更多还原

【Abstract】 The pollution of chlorinated organic compounds has been a problem needing to be solved urgently due to their great harm to the health of environment and human beings. In this paper, the dechlorination degradation behaviors of tetrachloride carbon and tetrachloroethene by nanoscale iron particles were studied systemically. In the experiment, two experiment projects of ultrasound synergized with nanoscale iron and ultrasound, water-bath type rocking bed synergized with nanoscale iron were adopted. By measuring the dechlorination efficiency of CCl₄ and C₂Cl₄ and using the ion selective electrode measure the chloride concentration, the effect of six influencing factors was observed. The six influencing factors included the initial pH of the medium, the content of nanoscale iron particles, reaction temperature, rotating speed, dechlorination time and the primal concentration of CCl₄ and C₂Cl₄. At the same time, the excellent dechlorination technics of CCl₄ and C₂Cl₄ were gained.Nanoscale iron particles were prepared by a sequential microwave thermal decomposition of Ferric Oxalate, and characterized by Rise-2008 Laser Grain-size Analyzer. The particles diameter was smaller and the particles size distribution was uniform.The results of the degradation of CCl₄ by ultrasound synergized with nanoscale iron showed that nanoscale iron particles and ultrasound intensified each other, which increased the dechlorination effect of CCl₄ greatly. With the improvement of更多还原