Arsenic removal from groundwater of the Chaco-Pampean Plain (Argentina) using natural geological materials as adsorbents

J. BUNDSCHUH; P. BHATTACHARYA; O, SRACEK; M.F. MELLANO; A. E. RAMIREZ; A. STORNIOLO; J. CORTÉS; M.I. LITTER; J.-S. JEAN

Journal of Environmental Science and Health

Taylor and Francis

Año: 2011

1532-4117

Use of natural geological materials for arsenic (As) removal is an emerging solution at ahousehold level for poor people in remote rural settlements, especially when the materials arelocally available and can be collected by the local population. Their low or zero cost makesthese materials very attractive compared with synthetic or commercial materials. Sometimes,this may be the only option to provide safe water to very poor settlements. Their suitabilityfor As removal from water is mainly due to adsorption, co-precipitation and ion exchange involving Fe- and Al-rich minerals and clay minerals present in the soils orsediments.In the present study, various clay-rich soils from the Santiago del Estero province (SDE, NWArgentina) and, for comparison, a laterite from the Misiones province have been tested asadsorbents for As in shallow naturally contaminated groundwaters of the Río Dulce alluvialaquifer in SDE. Batch adsorption experiments showed higher As(V) removal for the Misioneslaterite sample (99%) as compared with the soils from SDE (40-53%), which can be related tolower contents of water-soluble and oxalate extractable Al and Fe in the last samples. Theseresults suggest the application of the Misiones laterite soil as an alternative for As removal.However, high transportation costs from Misiones to SDE can be an economical restrictionfor the low-income populations of SDE.