O material CaTiO3 do tipo perovskita foi sintetizado pelo método dos precursores poliméricos e caracterizado. Os parâmetros da reação fotocatalítica foram otimizados pela metodologia de análise de superfície de resposta na degradação do azul de metileno sob radiação UV. Após a otimização, as águas residuais têxteis e de curtume foram tratadas e a redução da DQO foi avaliada. Em condições otimizadas (pH = 11,2 e 1 g L-1 de concentração de catalisador), os resultados obtidos para a fotodegradação dos efluentes reais após 240 min de irradiação foram de 45% de redução de DQO para os dois efluentes. As reações foram ajustadas para a cinética de pseudo primeira ordem e as constantes de velocidade foram 2,07 x 10-3 (min-1) e 2,23 x 10- 3 (min-1) para redução de DQO para o efluente têxtil e de curtume, respectivamente.
Palavras-chave: efluente de curtume, efluente têxtil, fotocatalisador, fotocatálise, perovskita, titanato de cálcio.
Perovskite-type CaTiO3 material was synthesized by the polymeric precursor method and characterized. The powder was applied as a promising alternative to TiO2 photocatalyst. Photocatalytic reaction parameters were optimized by surface analysis methodology on the degradation of methylene blue under UV radiation. After optimization, complex textile- and tannery wastewaters were treated and the COD reduction was evaluated. At optimized conditions (pH=11.2 and 1 g L-1 of catalyst concentration), the results obtained for the photodegradation of the real wastewater after 240 min of irradiation were 45% COD reduction for both effluents. The reactions were adjusted to the pseudo first order kinetic and the rate constants were 2.07 x 10-3 (min-1) and 2.23 x 10- 3 (min-1) for COD reduction for textile- and tannery wastewaters, respectively.
Perovskite-type CaTiO3 material was synthesized by the polymeric precursor method and characterized. The powder was applied as a promising alternative to TiO2 photocatalyst. Photocatalytic reaction parameters were optimized by surface analysis methodology on the degradation of methylene blue under UV radiation. After optimization, complex textile- and tannery wastewaters were treated and the COD reduction was evaluated. At optimized conditions (pH=11.2 and 1 g L-1 of catalyst concentration), the results obtained for the photodegradation of the real wastewater after 240 min of irradiation were 45% COD reduction for both effluents. The reactions were adjusted to the pseudo first order kinetic and the rate constants were 2.07 x 10-3 (min-1) and 2.23 x 10- 3 (min-1) for COD reduction for textile- and tannery wastewaters, respectively.
