AWWA JAW69263

A successful arsenic removal technology must becapable of removing both arsenate and arsenite.Research has shown that low-pressure nanofiltration(NF) membranes remove most of the arsenate but onlysome of the arsenite. To exploit membrane filtration'sability to remove arsenate, several researchers havesuggested that a pretreatment step oxidizing arsenite toarsenate would improve the performance of NF membranes.The current study investigated this hypothesis byassessing the effect of the oxidation step on the arsenicremoval performance of two NF membranes and a low-energyreverse osmosis membrane.Because of its inert nature, long life, simple operation,and compatibility with oxidant-sensitive membranes,manganese dioxide was chosen as the companionoxidant for membrane filtration. Resultsindicated that preoxidation with manganese dioxidesignificantly enhanced arsenic removal. For treatmentfacilities using membrane filtration to treathard or brackish water, manganese dioxide mayprovide a low-maintenance, cost-effective pretreatmentalternative if additional arsenic removal isrequired to meet the regulatory target of 10 µg/Larsenic. Includes 38 references, tables, figures.

Product Details

Edition:

Vol. 100 - No. 12

Published:

12/01/2008

Number of Pages:

10

File Size:

1 file