AWWA JAW65357

This research was undertaken to evaluate the feasibilityand cost-effectiveness of granular ferric hydroxide(GFH) for arsenic removal, in response to the 2002US Environmental Protection Agency (USEPA) lowering of the arsenic maximum contaminantlevel to 10 µg/L in drinking water. The research modeledthe adsorption activation energy, kinetics, andisotherm thermodynamic parameters. Results showGFH to be a promising and cost-effective arsenic(V), orAs(V), sorbent. GFH adsorbs As(V) readily and has alarge As(V) adsorption capacity indicated by kineticsand isotherm models. The adsorption is nonlinear, heterogeneous,and multilayered. It can also be compromisedby the presence of competitive anions, such assilica, vanadium, selenium, and phosphate in naturalwaters. The interference of silica, for example, mayrequire a pretreatment step to prolong the life of GFHas an arsenic sorbent. This could be achieved throughthe commonly used unit process of coagulation/flocculation.The thermodynamics parameters established forGFH As(V) removal will help water utility managerscompare and find the most suitable arsenic removalstrategy to meet the needs of their utilities. Includes 33 references, tables, figures.

Product Details

Edition:

Vol. 99 - No. 11

Published:

11/01/2007

Number of Pages:

11

File Size:

1 file , 320 KB