Showing papers by "Marta I. Litter published in 2005"
01 Jan 2005
TL;DR: An overview of photochemical advanced Oxidation technologies (PAOTs) is given, together with recent relevant literature examples and references in this article, where fundamental grounds with mechanistic pathways are described in each case.
Abstract: In this chapter, an overview of Photochemical Advanced Oxidation Technologies (PAOTs) is given, together with recent relevant literature examples and references. ShortUV and VUV photolysis, UV/H2O2, UV/O3, UV/O3/H2O2, photo-Fenton and iron-based technologies, photo-ferrioxalate and UV/periodate, are exposed, together with a brief introduction of heterogeneous photocatalysis. Fundamental grounds with mechanistic pathways are described in each case. Combination of PAOTs with other treatments (espe-
93 citations
TL;DR: In this paper, photo-Fenton (PF) reaction was used to degrade oxalic acid (ox) at relatively high concentrations (0.032 m) and the results indicated that, at a fixed iron concentration, H 2 O 2 increased the initial HP reaction rate and reduced the TOC 95.
59 citations
TL;DR: In this article, a detailed mechanism for the photocatalytic reaction of nitrilotriacetic acid (NTA) at pH 2.5 was studied to establish the kinetic regime and the reaction mechanism.
Abstract: TiO2-heterogeneous photocatalysis of nitrilotriacetic acid (NTA) at pH 2.5 was studied to establish the kinetic regime and the reaction mechanism. Pure Degussa P-25 and Hombikat UV100 commercial samples were compared. A Langmuirian behavior was observed over P-25. Platinization of the Hombikat sample (0.5 wt.%) caused an important increase on the photocatalytic rate with a change in the kinetics from zero order in the pure precursors to first order in the platinized sample. The nature of the intermediates and their evolution with time were compared on all systems. Glycine, iminodiacetic and oxamic acids have been identified in different proportions, together with ammonium and glycolic acid, depending on the catalyst used. The rapid depletion of NTA was not accompanied by a corresponding total organic carbon (TOC) reduction, but 84% of TOC decrease was obtained on P25 after 24 h, a very reasonable result for refractory compounds. A detailed mechanism is proposed for the photocatalytic reaction, suggested to be the same over the three catalysts here tested.
12 citations