Arsenic removal efficiency and mechanisms by electro-chemical precipitation process
This research was conducted to investigate the efficiency and mechanisms of arsenic (As) removal from a contaminated water by using the electro-chemical precipitation (ECP) process, with the operating conditions as follows: initial As concentration of 0.5-5 mg/L, 0.1 M KCl, electrical gradient of 20...
Veröffentlicht in: | Water science and technology : a journal of the International Association on Water Pollution Research. - 1986. - 46(2002), 9 vom: 21., Seite 247-54 |
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Weitere Verfasser: | , , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2002
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Zugriff auf das übergeordnete Werk: | Water science and technology : a journal of the International Association on Water Pollution Research |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Arsenic N712M78A8G |
Zusammenfassung: | This research was conducted to investigate the efficiency and mechanisms of arsenic (As) removal from a contaminated water by using the electro-chemical precipitation (ECP) process, with the operating conditions as follows: initial As concentration of 0.5-5 mg/L, 0.1 M KCl, electrical gradient of 200 V/m and initial pH higher than 3. The laboratory-scale ECP unit was able to reduce As to within the WHO drinking water standard of 0.01 mg/L in 20 min. The Cl- salt was found to yield better As removal efficiencies than the NO3- salt probably because NO3- ions interfered with the production of OH- and Fe(OH)3, important for As removal. X-ray fluorescence and X-ray diffractometric analysis revealed maghemite (Fe2O3) and angelellite (Fe4As2O11) to be the major compounds present in the precipitated sludge. The percent Fe2O3 and Fe4As2O11 contents of the dried ECP sludge were 98.29% and 0.26%, respectively. From a mass balance analysis, As removal in the ECP process was due to: incorporation in and adsorption on the ECP sludge--64.9-94.9%, conversion to arsine (AsH3) gas--10.5-15.6%, adsorption on the electrode plates and reactor walls--0.03-1.1%, residual in the supernatant--0.2-0.4%, and unaccounted for--1.2-19.8% |
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Beschreibung: | Date Completed 10.03.2003 Date Revised 21.11.2013 published: Print Citation Status MEDLINE |
ISSN: | 0273-1223 |