ADSORCIÓN DE ALDEHÍDOS INSATURADOS SOBRE TiO2 ADSORPTION OF UNSATURATED ALDEHYDES ON TiO2

In this work, the unsaturated aldehydes adsorption on TiO2 surface was studied. To test their efficiency as catalyst, experiments on heterogeneous photocatalysis of p-nitrophenol (PNP) and a sample obtained from an oil industry effluent were carried out using a solar simulator and modified-TiO2 systems. The systems of TiO2 used were: TiO2 pure (without modifying) and TiO2-dienal systems constituted by the chemical adsorption of 2,4 hexadienal, 2,4 heptadienal and trans-cinamaldehyde on the surface of the TiO2. Adsortions were well adjusted according to Langmuir and Freundlich isotherm. Also we evaluated the influence of pH in the systems TiO2dienal and its effect in the photocatalytic degradation of PNP. In basic conditions, the rate constant of the PNP was larger in precense of the TiO2-dienal systems when compared to the TiO2 pure, whereas in acid conditions we found the opposite tendency. The system TiO2-cina turned out to be the photocalyst of better efficiency of the photocalysis process.