Degradação do corante tartrazina utilizando o TiO2: Ce em um sistema conjugado dos processos eletroquímico/fotocatalítico

Imagem de Miniatura

Data

2015-06-12

Título da Revista

ISSN da Revista

Título de Volume

Editor

Universidade Federal de Goiás

Resumo

The effects of inclusion of cerium ions on the photocatalytic activity of TiO2 were studied in this work, so that the tartrazine dye, a food dye belongs to the class of azo compounds, it was degraded. Characterization techniques such as X-ray diffraction (XRD), diffuse reflectance (UV-VIS) and scanning electron microscopy (SEM) were used to understand the relationship between structure and photocatalytic activity for the oxides synthesized by the method of polymeric precursors with different temperatures of calcination. According to the analysis by X-ray diffraction, the crystalline anatase phase was predominant on calcinations at temperatures equal to and less than 750 ° C for the synthesized compounds. Photocatalytic degradation of the dye Tartrazine, catalyzed by the synthesized compounds was evaluated and compared to P25 (trade photocatalyst) and undoped titanium oxide. Best performance was observed in the photocatalytic activity of P25, followed by titanium oxide doped cerium ten percent and finally the non-doped titanium oxide, respectively obtaining an elimination of 100% color; 45.92% and 33.89% in 60 min, 71.18% and reaching 57% at 120 min respectively for the titanium oxide doped with ten percent of cerium and titanium oxide undoped flow reactor. Thus it is clear that doping the material improved photocatalytic performance. For coupling techniques were performed in three electrolysis current density: 10; 30 and 50 mA / cm2, yielding an elimination of color respectively 26.25%; 37.94% to 40.67%, in this case, the process efficiency is not only related to color removal also depends on the energy consumption, which was 0.26 kWh / g; 0.88 kWh / g 1.85 kWh / g for current densities of 10; 30 and 50 mA / cm2, respectively, and the current density of 30 mA / cm2 showed the most money. Having optimized the two processes, one can then perform the photoelectrochemical experiments, whereas for all three catalysts studied, the combined processes (photoelectrochemical) performed better compared to the separate processes, respectively being obtained discoloration of 100%; 48.82% and 39.00% in 60 min, reaching 73.26% and 65.54% respectively for 120 min in titanium oxide doped with ten percent of cerium and titanium oxide undoped.

Descrição

Palavras-chave

Dióxido de titânio, Precursores poliméricos, Fotocatálise heterogênea, Eletroquímica, Fotoeletroquímica, Degradação e tartrazina, Titanium dioxide, Polymeric precursor, Heterogeneous photocatalysis, Electrochemical, Photoelectrochemical, Degradation and tartrazine

Citação

SOUZA, C. R. Degradação do corante tartrazina utilizando o TiO2: Ce em um sistema conjugado dos processos eletroquímico/fotocatalítico. 2015. 52 f. Dissertação (Mestrado em Química) - Universidade Federal de Goiás, Catalão, 2015.