کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6465966 1422958 2017 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Removal efficiency and economic cost comparison of hydrated electron-mediated reductive pathways for treatment of bromate
ترجمه فارسی عنوان
کارایی حذف و مقایسه هزینه های اقتصادی مسیرهای کاهش دهنده هیدراتهای الکترون برای درمان برومات
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی مهندسی شیمی (عمومی)
چکیده انگلیسی


- Efficiency of sulfite coupled with UV-254 in the removal of bromate was explored.
- The eaq− yield in UV-254/SO32− process was verified using different eaq− scavengers.
- Impacts of different competitors on the reactivity of eaq− with bromate were explored.
- Second-order rate constant of bromate with eaq− was determined.
- Proposed pathways for conversion of bromate into bromide were developed.

Bromate, a potential carcinogen, is a well known highly persistent and environmentally recalcitrant contaminant. UV-254/sulfite-based advanced reductive pathways (ARPs) were proposed to eliminate bromate successfully from water. Experiments with N2, N2O, 2-chlorophenol, inorganic ions, and different pH (highly acidic to highly basic) proved that UV-254/sulfite successfully provides aqueous electron that effectively participate in bromate removal from water. Significant removal, 86%, of initially 39.0 µM bromate was achieved by UV-254/sulfite under conditions that dominate aqueous electron based pathways. The high second-order rate constant of 5.3 × 109 M−1 s−1 determined proved high reactivity of aqueous electron with bromate. The kinetic and removal efficiency of bromate showed linear relationship with the rate of aqueous electron formation. An increase in kinetic and removal efficiency of bromate was observed with increasing initial sulfite concentration and decreasing bromate concentration. The impacts of different initial concentrations of the typical ions commonly found in water were studied in detail to extend the UV-254/sulfite-based process for potential practical applications. The lower molar absorptivity of bromate at 254 nm determined proved insignificant removal of bromate under direct photolysis. The impacts of initial sulfite concentration on removal of bromate in UV-254/sulfite-based process also minimized role of direct photolysis. The cost evaluation and rapid decomposition of bromate into bromide proved UV-254/sulfite-based ARPs to be economical and highly rewarding in efficient decomposition of bromate and other inorganic oxyhalides.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemical Engineering Journal - Volume 320, 15 July 2017, Pages 523-531
نویسندگان
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