Castro Guerrero, Brenda AstridHuetio Vergara, Viviana AndreaMera Benavides, Adriana Consuelo2012-07-132012-07-1320081909-0455http://hdl.handle.net/10567/537Introduction. The heterogeneous photocatalysis using titanium dioxide in suspension is an efficient technology that at the moment is applied for the degradation of recalcitrant contaminants. The use of this technique is a good alternative for the degradation of the acid-base phenolphthalein indicator, present on the liquid wastes generated by the laboratories of chemical analysis in the University of Cauca. Objective. To apply the heterogeneous photocatalysis using TiO2 suspended and H2O2, in the treatment of liquid wastes with the phenolphthalein indicator. Materials and equipment. For the photocatalysis process, a system composed of three parts was used: A photo-reactor with a lamp of ultraviolet light that has a tube of low pressure of mercury (wavelength 254 nm), a zone of homogenization and a pump for the recirculation of the sample. The conditions from which the highest percentage of degradation of the indicator was obtained, were analyzed. The specific variables analyzed in this treatment were: catalyst concentration (TiO2 Degussa P25), oxidinsing agent concentration (H2O2), and the time of exhibition to the light Uv. Results.The degradation and mineralization of the indicator in the process were evaluated by using colorimetric methods. Results. the highest percentage of degradation was 86,54% using 500 ppm of TiO2, 2600 ppm of H2O2, and 8 hours of light Uv time exposition. These standardized conditions were applied for the liquid wastes. Conclusion. the use of optimum concentrations of TiO2 and H2O2 allows to obtain good degradation percentages of the acid-base phenolphthalein indicator present in chemical wastes.esFotocatálisis heterogéneaPeróxido de hidrógeno (H2O2)Corporación Universitaria LasallistaÁrea Metropolitana del Valle de AburráFenolftaleínaDióxido de titanio (TIO2)Aguas residualesAguas residuales industrialesTratamiento de aguas residualesContaminación del aguaFotocatálisis heterogénea con TiO2 y H2O2 para el tratamiento de desechos líquidos con presencia de Fenolftaleína generados en los laboratorios de análisis químico de la Universidad del CaucaHeterogeneous photocatalysis with Tio2 and H2O2 for the treatment of liquid wastes with phenolphthalein, generated in the chemical analysis laboratories of the University of CaucaFoto-catálisis Heterogênea com TiO2 e H2O2 para o tratamento de refugos líquidos com presença de Fenolftaleína gerados nos laboratórios de análise química da Universidade del CaucaArticle