Environmental Engineering Reference
In-Depth Information
3
New Generation Material for the Removal
of Arsenic from Water
Dinesh Kumar* and Vaishali Tomar
Department of Chemistry, Banasthali Vidyapith, Rajasthan, India
Abstract
Arsenic (As) is a noxious constituent whose role in water pollution has received
extensive attention in the scientii c community. It is mobilized into surface water
during industrial waste discharges, agricultural use of arsenical pesticides, her-
bicides, fertilizers, discharges from coal-i red thermal power plants, petroleum
rei ning and ceramic industries, etc. In the last 20 years, naturally occurring arse-
nic has been found in the natural waters of the USA, Argentina, Taiwan, China,
Hungary, Vietnam, Chile, Bangladesh and India. h is is of concern because a
high level of arsenic (>10 μg/L) may increase the risk for many health problems,
some of which are discussed herein. However, numerous studies have established
that arsenic removal can be achieved by a range of techniques, specii cally solvent
extraction, chemical precipitation as synthetic coagulants, iron co-precipitation,
ion exchange and reverse osmosis, etc. In this chapter many of the adsorbents
used for arsenic removal are reviewed along with several inexpensive adsor-
bents for advanced techniques including treated slags, carbons developed from
agricultural waste, biosorbents, zeolites and some commercial adsorbents. Also
included are the resins, gels, silica, and treated silica tested for arsenic removal,
which have been found to be superior. Immobilized biomass adsorbents, which
of er wonderful performances, are also discussed. By surveying the extensive list
of adsorbents compiled from literature presented here it is evident that low-cost
sorbents have demonstrated outstanding arsenic removal capabilities. In particu-
lar, nanomaterial-based adsorbents might be promising adsorbents for environ-
mental and purii cation purposes.
Keywords
:
Removal, arsenic, adsorbents
Search WWH ::
Custom Search