AWWA ACE61618

This paper discusses enhanced removal of dissolved natural organic matter (DOM) by modified granularactivated carbon (GAC). GAC was modifiedby high temperature ammonia and steam treatment, respectively. Both techniquesincreased the carbon mesoporosity and surface basicity. Adsorption isotherms indicatedthat ammonia- and steam-treated carbons exhibited higher dissolved organic matter (DOM) uptake than theprecursor mainly due to the enlargement of carbon pores. Rapid small scale column tests(RSSCTs) showed that steam treatment almost doubled the volume of treated water toreach 50% breakthrough compared to the virgin GAC. Several iron impregnationmethods were used to load iron species on the carbon surface. Surface-area normalizedisotherms showed that some iron impregnated carbons had higher DOM uptake due to thepresence of iron species on the carbon surface. However, not all the iron species werefavorable for the adsorption. Iron oxidation state and particle size appear to be important.GAC with higher mesoporosity and proper iron dispersion on the surface was expectedto exhibit higher DOM uptakes from natural waters. Includes 12 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

06/17/2005

Number of Pages:

16

File Size:

1 file , 2.2 MB