【摘要】 研究对比了热,碱和Fe₃O₄ 3种方法激活过硫酸钠对二恶烷的降解情况.结果表明,加碱且反应液p H值不超过12h,过硫酸钠对二恶烷的降解受到了抑制.加热可以有效激活过硫酸钠降解二恶烷,在40℃、过硫酸钠与二恶烷的物质的量比为20:1的条件下,反应48h时二恶烷的降解率达98%,降解反应的准一级反应速率常数为68.1×10-6h-1.非均相体系中,Fe₃O₄也可显著激活过硫酸钠降解二恶烷,过硫酸钠与二恶烷的物质的量比为80:1,Fe₃O₄与混合溶液固液比仅为1:100时,二恶烷降解的准一级反应速率常数为61.1×10-6h-1,接近上述加热激活的水平.Fe₃O₄激活过硫酸根降解二恶烷时,由于过硫酸根优先与二恶烷反应而不是Fe₃O₄发生反应,因此在二恶烷降解完成之前溶解态Fe产生量低、Fe₃O₄消耗少.该研究结果反映出应用Fe₃O₄激活过硫酸盐的方法修复有机污染地下水的较大潜力.更多还原

【Abstract】 In this study activation of persulfate by heat, base, and magnetic oxide（Fe₃O₄） for degradation of 1.4-dioxane was investigated and compared. The results showed that degradation of 1,4-dioxane was inhibited in the base-activation system with p H low than 12. Heat was effective for persulfate activation to degrade 1,4-dioxane. When the temperature was 40℃ and the molar ratio of persulfate and 1,4-dioxane was 20:1, the percentage of 1,4-dioxane removal reached 98% in 48 h and the pseudo-first-order reaction rate constant was 68.1×10-6h-1. Degradation of 1,4-dioxane was also significant in the heterogeneous system with Fe₃O₄ as the activator. When the molar ratio of persulfate and 1,4-dioxane was 80:1 and the solid-liquid ratio between Fe₃O₄ and solution was 1:100, the pseudo-first-order reaction rate constant for 1,4-dioxane removal was 61.1×10-6h-1, which was close to that obtained with heating（40℃） as the activation method. In this Fe₃O₄-based heterogeneous activation system, production of soluble Fe and consumption of Fe₃O₄ were minimal before depletion of 1,4-dioxane, which is due to preference of the reaction between persulfate and 1.4-dioxane to the reaction between persulfate and Fe₃O₄. The results of this study indicated the potential of application of the Fe₃O₄-based method for persulfate activation for remediation of groundwater contaminated by organic compounds.更多还原