Photocatalytical removal of inorganic and organic arsenic species from aqueous solution using zinc oxide semiconductor.
The photocatalytic removal of arsenite [As(III)] and monomethylarsonic acid [MMA(V)] was investigated in the presence of UV light (350 nm) and aqueous suspensions of ZnO synthesized by the sol-gel technique. Photocatalytic removal of these potent arsenic compounds results in the effective and rapid mineralization to less toxic inorganic arsenate [As(V)]. The effect of ZnO loading and solution pH on the treatment efficiency of the UV/ZnO photocatalytic process was evaluated. The optimal conditions for the removal of 5 mg L(-1) [As(III)] and [MMA(V)] aqueous solutions were observed at catalyst loadings of 0.25 and 0.50 g L(-1) with solution pH values of 7 and 8, respectively. Under these conditions, the activity of photocatalyst sol-gel ZnO was compared with TiO2 Degussa P25 and commercial ZnO catalyst. The results demonstrate that the high adsorption capacity of ZnO synthesized by sol-gel gives enhanced removal of arsenic species from water samples, indicating that this catalyst is a promising material for treatment of arsenic contaminated groundwater.
Universidad Autónoma de Nuevo León, UANL, Department of Chemistry Sciences, San Nicolás de los Garza, N.L., 66451, México.
Nidia
N
Rivera-Reyna
Laura
L
Hinojosa-Reyes
Jorge Luis
JL
Guzmán-Mar
Yong
Y
Cai
Kevin
K
O'Shea
Aracely
A
Hernández-Ramírez
D000327:Adsorption; D001152:Arsenicals / Q000737:chemistry*; D018053:Arsenites / Q000737:chemistry* / Q000302:isolation & purification; D002384:Catalysis; D005782:Gels / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D012666:Semiconductors; D014025:Titanium / Q000737:chemistry; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000302:isolation & purification; D018508:Water Purification; D015034:Zinc Oxide / Q000737:chemistry*
D001152:Arsenicals; D018053:Arsenites; D005782:Gels; D014874:Water Pollutants, Chemical; C009495:titanium dioxide; D014025:Titanium; C020300:monomethylarsonic acid; C015001:arsenite; D015034:Zinc Oxide