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Degradation of 1,4-dioxane in Water With Heat- And Fe(2+)-activated Persulfate Oxidation

Long Zhao, Hong Hou, Ayuko Fujii, Masaaki Hosomi, Fasheng Li

Environ Sci Pollut Res Int. 2014 Jun;21(12):7457-65.

PMID: 24590601

Abstract:

This research investigated the 1,4-dioxane (1,4-D) degradation efficiency and rate during persulfate oxidation at different temperatures, with and without Fe(2+) addition, also considering the effect of pH and persulfate concentration on the oxidation of 1,4-D. Degradation pathways for 1,4-D have also been proposed based on the decomposition intermediates and by-products. The results indicate that 1,4-D was completely degraded with heat-activated persulfate oxidation within 3-80 h. The kinetics of the 1,4-D degradation process fitted well to a pseudo-first-order reaction model. Temperature was identified as the most important factor influencing the 1,4-D degradation rate during the oxidation process. As the temperature increased from 40 to 60 °C, the degradation rate improved significantly. At 40 °C, the addition of Fe(2+) also increased the 1,4-D degradation rate. Interestingly, at 50 and 60 °C, the 1,4-D degradation rate decreased slightly with the addition of Fe(2+). This reduced degradation rate may be attributed to the rapid conversion of Fe(2+) to Fe(3+) and the production of an Fe(OH)3 precipitate which limited the ultimate oxidizing capability of persulfate with Fe(2+) under higher temperatures. Higher persulfate concentrations led to higher 1,4-D degradation rates, but pH adjustment had no significant effect on the 1,4-D degradation rate. The identification of intermediates and by-products in the aqueous and gas phases showed that acetaldehyde, acetic acid, glycolaldehyde, glycolic acid, carbon dioxide, and hydrogen ion were generated during the persulfate oxidation process. A carbon balance analysis showed that 96 and 93% of the carbon from the 1,4-D degradation were recovered as by-products with and without Fe(2+) addition, respectively. Overall, persulfate oxidation of 1,4-D is promising as an economical and highly efficient technology for treatment of 1,4-D-contaminated water.

Chemicals Related in the Paper:

Catalog Number Product Name Structure CAS Number Price
AS2121363 1,4-Dioxane in Water 1,4-Dioxane in Water Price
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