کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
640185 884242 2015 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Efficient selenate removal by zero-valent iron in the presence of weak magnetic field
ترجمه فارسی عنوان
حذف سلنیت کارآمد توسط آهن صفر دلپذیر در حضور میدان مغناطیسی ضعیف
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی تصفیه و جداسازی
چکیده انگلیسی


• Efficient Se(VI) removal was achieved by ZVI at very low dosage coupling with WMF.
• The rate of Se(VI) removal by ZVI with WMF increased with increasing ZVI dosage.
• Se(VI) adsorption to the ZVI surface was the first step of Se(VI) removal by ZVI.
• The adsorbed Se(VI) was rapidly reduced to Se(IV) and then slowly to Se(0).
• Employing WMF to enhance Se(VI) removal by ZVI under oxic conditions is promising.

Se(VI) was very refractory to be removed by zero-valent iron (ZVI), therefore weak magnetic field (WMF) was employed to achieve efficient Se(VI) removal by ZVI. Batch experiments showed that negligible Se(VI) (<4%) was removed by ZVI without the application of WMF within 72 h. The presence of WMF dramatically enhanced Se(VI) sequestration by ZVI and complete removal of 10.0 mg L−1 Se(VI) was achieved by ZVI in 90 min. The main portion of kinetics of Se(VI) removal by ZVI in the presence of WMF followed zero-order rate law and the rate constants of Se(VI) sequestration by ZVI increased progressively with increasing the ZVI dosage. Fe K-edge XAFS spectra and synchrotron radiation-XRD analysis revealed that ZVI was transformed to X-ray amorphous Fe3O4 before finally transformed to lepidocrocite (γ-FeOOH). The LCF analysis of Se K-edge XANES spectra indicated that adsorptive removal of Se(VI) was minor but adsorption of Se(VI) to the corroded ZVI surface was the first step of Se(VI) removal. Se(VI) was rapidly reduced to Se(IV), which could be further transformed to Se(0). Comparison of the performance of Se(VI) removal in the literature suggested that employing WMF to enhance Se(VI) removal by ZVI under oxic conditions be a promising method.

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ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Separation and Purification Technology - Volume 156, Part 3, 17 December 2015, Pages 1064–1072
نویسندگان
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