Arsenic immobilization in soils amended with drinking-water treatment residuals.
Use of Fe/Al hydroxide-containing materials to remediate As-contaminated sites is based on the general notion that As adsorption in soils is primarily controlled by Fe/Al (hydr)oxides. A low-cost and potentially effective substitute for natural Fe/Al hydroxides could be the drinking-water treatment residuals (WTRs). Earlier work in our laboratory has shown that WTRs are effective sorbents for As in water. We hypothesized that land-applied WTRs would work equally well for As-contaminated soils. Results showed that WTRs significantly (p<0.001) increased the soil As sorption capacity. All WTR loads (2.5, 5, and 10%) significantly (p<0.001) increased the overall amount of As sorbed by both soils when compared with that of the unamended controls. The amount of As desorbed with phosphate (7500 mg kg(-1) load) was approximately 50%. The WTR effectiveness in increasing soil As sorption capacities was unaffected by differences in both soils' chemical properties.
Sarkar
Dibyendu
D
Department of Earth and Environmental Science, University of Texas at San Antonio, 6900 North Loop 1604 West, San Antonio, TX 78249-0663, USA. dibyendu.sarkar@utsa.edu
Makris
Konstantinos C
KC
Vandanapu
Vandana
V
Datta
Rupali
R
D000327:Adsorption; D000536:Aluminum Hydroxide / Q000737:chemistry; D001151:Arsenic / Q000737:chemistry*; D004326:Drinking; D005290:Ferric Compounds / Q000737:chemistry; D006801:Humans; D008670:Metals / Q000737:chemistry; D010575:Pesticides / Q000737:chemistry; D012987:Soil; D012989:Soil Pollutants / Q000737:chemistry*; D013997:Time Factors; D018508:Water Purification
D005290:Ferric Compounds; D008670:Metals; D010575:Pesticides; D012987:Soil; D012989:Soil Pollutants; D000536:Aluminum Hydroxide; D001151:Arsenic