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The heterogeneous photocatalytic degradation of dyes reactive red 120 and reactive blue 4 under ideal solutions and hydrolysates dyes simulating a staining process with an initial concentration of 50 mg • L-1 was studied, using 200 mg • L-1 of TiO2 doped with Fe or N. Total degradation of both dyes was achieved with the addition of an auxiliary oxidizing agent such as hydrogen peroxide (H2O2) at a concentration of 12.0 mM. Such degradation was achieved after one hour of reaction for doped catalysts (N-TiO2 and Fe-TiO2). For solutions of hydrolysed dye that simulated waste water from the textile industry was found that the pH adversely affects dye degradation due to repulsion between the photocatalysts and dyes. In all the studied cases further degradation of reactive red dye 120 was observed relative to reactive blue 4, which can be associated with the complex molecular structure of the second dye. [ABSTRACT FROM AUTHOR]

Effectiveness of heterogeneous photocatalysis using TiO2 in the degradation of organic matter from an effluent of pharmaceutical industry was evaluated. The results show that the studied variables (initial pH, concentration of TiO2 and H2O2) affect the removal efficiency of organic matter. The highest levels of COD (70.4%), BOD (96.7%) and TOC (81.4%) removal were obtained using 340 mg/L of TiO2, 10.0 mM of H2O2 at pH initial 7.0 and an UV light exposure time of 5 hours. [ABSTRACT FROM AUTHOR]

The activity of 5%Pd/TiO2 and for the first time 5%Pd/TiO2-5%Na catalysts was evaluated in the liquid phase catalytic hydrodechlorination of chloroform at room temperature and 50°C, using isopropanol as solvent and hydrogen donor. 5%Pd/TiO2-5%Na catalyst showed the best catalytic performance at room temperature and 50°C, with the highest conversion at 50°C (32.5%) after 5 hours of reaction. The incorporation of sodium ions into the support favored both the dehydrogenation of isopropanol and the capture of chloride ions produced during the reaction, both positive for the hydrodechlorination of chloroform. The catalysts were characterized by AAS, mass titration, XRD, BET, hydrogen chemisorption, TPR and TGA. Na and Pd were loaded on the support practically without loss. and the anatase phase of titanium dioxide did not change with the addition of NaOH increased the catalyst's isoelectric point, indicating an increase in catalyst basicity. This can explain the improved activity of Na-containing catalysts. [ABSTRACT FROM AUTHOR]