Chitosan dispersed with Fe (III) oxide particles: A sorbent used for selective removal of arsenic from contaminated waters

Abstract:

Arsenic (As) is a toxic metalloid that is ubiquitous in surface water and groundwater in trivalent and pentavalent form. Ingestion of As contaminated water is a public health problem world-wide (Roychowdhury et al. 2002, Meharg and Mazibur 2003). At chronic exposure, As accumulates in the human body and high levels causes skin affections. The epidemiologic evidence of people with a long ingestion of inorganic As, via drinking water, is the sole/palm hyperkeratosis, whose main manifestation is skin pigmentation and callosities, located in hand palms and sole feet. As in water and its degree of contamination and occurrence of skin illnesses have been reported in India, Bangladesh, Taiwan, Vietnam, Argentina, and Mexico (Cebrian et al. 1994, Das et al. 1994, Frederick et al. 1994, Brown and Chen 1995, Armienta et al. 1997, Dhar et al. 1997, Smith et al. 1998, Chakraborti et al. 2002). A number of conventional and emergent materials are used for As removal from water such as activated alumina, ion exchange resins, sand covered with iron oxides, granular ferric hydroxide, sands mixed with zerovalent iron, nanofiltration and reverse osmosis membranes, aluminum sulfate and ferric chloride coagulants, etc. Iron oxide particles are excellent materials to sorb chemical species, including metallic ions (Laxen 1983, Slavek and Pickering 1986, Music and Ristic 1992), inorganic anions (Pierce and Moore 1982, Manning et al. 1998), and some organic compounds (Matheson and Tratnyek 1994, Wang and Zhang 1997). Hydrated Fe (III) oxides (HFO) exhibit excellent properties conducive to a selective capture of trace contaminants due to its weak …

Año de publicación:

2010

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