EVALUATING ARSENIC AND MANGANESE REMOVAL FROM WATER BY CHLORINE OXIDATION FOLLOWED BY CLARIFICATION

• Published in: Brazilian journal of chemical engineering 2015-06, Vol.32 (2), p.409-419
• Main Authors: Pires, V. G. R., Lima, D. R. S., Aquino, S. F., Libânio, M.
• Format: Article
• Language: English
• Subjects: ENGINEERING, CHEMICAL
• ISSN: 0104-6632; 1678-4383; 0104-6632
• DOI: 10.1590/0104-6632.20150322s00003564

AbstractThis paper investigates the simultaneous removal of arsenic [As(V) or As(III)] and manganese [Mn(II)] from natural waters of low and high turbidity by clarification (with polyaluminum chloride and aluminum sulfate as primary coagulants) associated or not with chlorine pre-oxidation. The results showed that the clarification process exhibited low Mn(II) removal, that varied from 6% to 18% and from 19% to 27% for natural waters of low and high turbidity, respectively. The use of chlorine as pre-oxidant increased Mn(II) removal up to 77% and was associated with the formation of birnessite. Regarding As(V) removal by clarification, particularly for high turbidity water, a concentration lower than that established by the National Drinking Water Quality Standards (10 μg.L-1) was achieved in almost all tests. Oxidation preceding the clarification led to AsIII removal efficiencies from 80% to 90% for both coagulants and types of water.