Resumo

TAPIA, JAIME et al. ESTUDIO DE REDUCCIÓN FOTOCATALIZADA DE CROMO HEXAVALENTE. Bol. Soc. Chil. Quím. [online]. 2002, vol.47, n.4, pp. 469-476. ISSN 0366-1644.  http://dx.doi.org/10.4067/S0366-16442002000400018.

A methodology to decrease the chromium concentration Cr(VI) existing in tannery discharges is suggested. The proposal is based on a photocatalytic process in which the effluent is irradiated by UV light in presence of TiO₂ as a catalyst employing formaldehyde as a reductor agent. Were employed different Cr(VI) solutions of 100 mg/L as models at different pH, catalyst quanties and irradiation times. The variable optimization was made from multivaried analysis. The better conditions for to reduction a 50 ml of a Cr(VI) of 100 mg/L solutions were pH 2 at 20 minutes of UV irradiation and 40 mg of TiO₂ load. In these conditions it was possible a 97.8 % of Cr(VI) reduction level. For a real effluent from tannery industries the reduction level was 81.3 %.

Palavras-chave : hexavalent chromium; photocatalysis; tannery discharges.