氯对苯氧化过程影响机制的实验研究

针对高含氯垃圾气化-燃烧工艺中焦油的氧化裂解过程,利用均相管流反应器配合傅里叶红外光谱仪,以C_6H_6为焦油模型化合物,对比研究了氯参与前后,裂解产物组成和氧化完全程度随温度和当量比的变化,探索了氯对C_6H_6氧化裂解过程的影响机制。结果表明,低温下氯对C_6H_6的氧化有明显的激发作用,但由于氯对OH的消耗,对裂解产物进一步转化为完全氧化产物CO_2又存在抑制作用。此外,在高温低当量比条件下氯对聚合反应也有促进作用。因此,在工程应用中,高含氯垃圾气化产物的燃烧可适应更低的温度,但应避免高温低当量比反应环境的形成以避免聚合产物。此外,还应控制垃圾原料中的氯元素比例,以保障氧化反应的充分进行。

Experimental study on the effect of chlorine on benzene oxidation

To study the oxidative cracking process of tars during the combustion of syngas from MSW gasification, C₆H₆ was selected as the model compound, and the experiments of oxidation were carried out with and without Cl₂ in a homogeneous tubular flow reactor coupled with FT-IR. The oxidative products and oxidative degree as functions of temperature and ER were compared to reveal the effect of chlorine on C₆H₆ oxidation. The results indicate that chlorine has a clear excitation effect on C₆H₆ oxidation at low temperature. However, a further oxidation to CO₂ is inhibited by chlorine due to the increased OH consumption. Moreover, chlorine also promotes the polymerization reaction at high temperature and low equivalence ratio. Thus, the combustion of syngas from MSW gasification can proceed at lower temperature, while the environments with high temperature and low equivalence ratio should be avoided for the prevention of polymerization. Also, the chlorine content of MSW should be controlled to ensure the complete oxidation.