Low-cost solar technologies for arsenic removal in drinking water

M.E. MORGADA DE BOGGIO; I.K. LEVY; M. MATEU; J.M. MEICHTRY; S. FARÍAS; G.D. LÓPEZ; D. BAHNEMANN; R. DILLERT; M.I. LITTER

The Global Arsenic Problem: challenges for safe water production

CRC Press/Balkema, Taylor & Francis Group

Año: 2010; p. 209 - 218

This chapter compiles the study of the evaluation of the effectiveness of simple and lowcostsolar technologies for As removal from groundwater, based on heterogeneous photocatalysis(HP) and zerovalent iron (ZVI) technologies to remove As from laboratory water solutions. For HP tests, laboratory prepared and natural samples were placed in bottlesinternally covered by a TiO2 layer and exposed to solar or artificial UV light. By additionof iron in different forms (iron wool, packing wire or aqueous Fe(III)), simultaneously orafter the irradiation, As removal higher than 80% after 6 hours of irradiation was obtainedin all cases. ZVI tests with iron wool or packing wire yielded also good removals, althoughiron wool demonstrated to be a better iron material. Preliminary tests with commercialzerovalent nanoparticles (NZVI) resulted in outstanding results, rendering almost totalremoval with very low amounts of iron in very short contact times (typically under twohours). Natural waters from two localities of the Chacopampean Plain of Argentina werealso tested (Mateu 2007, Morgada et al. 2008, 2009, Morgada de Boggio et al. 2009). UVirradiation improved the results, especially in real waters. Although both methodologies,HP and ZVI yielded similar results, use of HP could be superior because simultaneousremoval of As, natural organic matter, organic pollutants, toxic metals and microbiologicalcontamination can be achieved.