卤素改性活性炭氧化单质汞的机理研究

发布时间：2018-03-06 09:42

本文选题：卤素　切入点：改性活性炭　出处：《工程热物理学报》2017年02期 　论文类型：期刊论文

【摘要】：采用量子化学密度泛函理论中B3LYP方法,研究了单质汞在卤素改性活性炭表面的氧化反应机理。选定七环锯齿形苯环簇为活性炭表面模型,设计了两种卤素改性活性炭模型X-AC和X-AC-X(X=Cl、Br、I)。通过得到氧化反应过程的过渡态,明确了氧化反应过程,并计算单质汞在改性活性炭表面的吸附能和氧化反应的能垒。研究结果表明:单质汞在负载三种不同卤素原子活性炭表面的吸附能的大小顺序均为:ClBrI,且从吸附强度角度分析,氯改性活性炭表面对单质汞的吸附最稳定。单质汞在负载三种不同卤素原子活性炭表面发生氧化反应的能垒大小顺序均为:ClBrI,且从反应发生难易角度分析,碘改性活性炭表面对单质汞的氧化反应最容易发生。单质汞在改性活性炭表面氧化反应的难易顺序可以正确解释改性活性炭脱除单质汞的实验现象。研究单质汞在改性活性炭表面氧化反应过程中的能垒,对于正确全面揭示改性活性炭脱除单质汞机理至关重要。
[Abstract]:The oxidation mechanism of elemental mercury on the surface of halogen modified activated carbon was studied by using B3LYP method in the density functional theory of quantum chemistry. Two kinds of halogen modified activated carbon models X-AC and X-AC-XAC-XCClC1-Br-I- were designed. The oxidation reaction process was determined by obtaining the transition state of the oxidation reaction process. The adsorption energy and the energy barrier of oxidation reaction of elemental mercury on the surface of modified activated carbon are calculated. The results show that the adsorption energy of elemental mercury on the surface of three different halogen atoms activated carbon is in the order of: 1 ClBrI, and the adsorption intensity is analyzed from the point of view of adsorption strength. The adsorption of elemental mercury on the surface of chlorinated activated carbon is the most stable. The order of energy barrier for the oxidation reaction of elemental mercury on the surface of three different halogen atomic activated carbon is in the order of: ClBrI, and analyzed from the point of view of the difficulty of reaction. The oxidation reaction of elemental mercury on the surface of iodine modified activated carbon is the easiest to occur. The order of simple mercury oxidation on the surface of modified activated carbon can correctly explain the experimental phenomenon of removing elemental mercury from modified activated carbon. The energy barrier in the surface oxidation reaction of modified activated carbon, It is very important to reveal the mechanism of mercury removal by modified activated carbon.
【作者单位】：华北电力大学能源动力与机械工程学院;
【基金】：中央高校基本科研业务费专项资金资助项目(No.10MG19)
【分类号】：X773;O613.71

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