Removal of 1,4-dioxane from water using sonication: effect of adding oxidants on the degradation kinetics.
Removal of 1,4-dioxane from water using sonication: effect of adding oxidants on the degradation kinetics.
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DOI：
10.1016/j.watres.2005.11.046
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发表时间：
2006-02
期刊：
影响因子：
12.8
通讯作者：
H. Son;Seok-Bong Choi;E. Khan;K. Zoh
中科院分区：
文献类型：
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作者：
H. Son;Seok-Bong Choi;E. Khan;K. Zoh
本研究考察了在超声处理1，4-二氧六环（1，4-D）过程中加入氧化剂如Fe 0、Fe 2+和S2 O 82-的影响。结果表明，1，4-D的降解动力学可分为起始、加速和稳定3个阶段，其中前两个阶段占主导地位。初始阶段符合零阶速率模型，加速阶段为伪一阶速率模型。在HCO 3-作为自由基清除剂的存在下，1，4-D和TOC的降解受到抑制，表明OH自由基是超声分解的重要因素，特别是在加速步骤。在200 min内，1，4-D的总降解率达到79.0%。当Fe 0、Fe 2+和S2 O 82-单独与超声联合处理时，200 min后1，4-D的总降解率分别提高了18.6%、19.1%和16.5%。氧化剂的加入不仅增加了加速步骤的速率常数，而且在引发步骤将动力学模型从零级改变为伪一级。在1，4-D的超声处理过程中加入氧化剂如Fe 2+、Fe 0和S2 O 82-也能促进1，4-D的矿化。然而，使用不同氧化剂（例如Fe 2+、Fe 0和S2 O 82-）时，1，4-D和TOC的降解效率没有统计学差异（p=0.709，方差分析）。
This research investigates the effect of adding oxidants such as Fe0, Fe2+and S2O82−in the sonication of 1,4-dioxane (1,4-D). The results indicate that the degradation pattern of 1,4-D kinetically could be divided into three steps (initiation, acceleration, and stabilization), with the first two steps predominating. The initiation step agreed with zero order rate model, while the acceleration step was the pseudo-first order. In the presence of HCO3−as a radical scavenger, the degradations of 1,4-D and TOC were suppressed, indicating that OH radical is an important factor in the sonolysis, especially at the acceleration step. The overall degradation efficiency of 79.0% in the sonolysis of 1,4-D was achieved within 200min. While Fe0, Fe2+and S2O82−were individually combined with sonication, the total degradation efficiency of 1,4-D increased 18.6%, 19.1% and 16.5% after 200min, respectively. The addition of oxidants not only increased the rate constant in the acceleration step, but also changed the kinetic model from zero to pseudo-first order at the initiation step. The addition of oxidants such as Fe2+, Fe0and S2O82−in the sonication of 1,4-D also improved the mineralization of 1,4-D. However, the degradation efficiencies of 1,4-D and TOC were not statistically different (p=0.709, ANOVA) with different oxidants such as Fe2+, Fe0and S2O82−.