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This research contributes to the study and development of a new degradation technique that couples solar and biological processes for the treatment of biorecalcitrant, nonbiodegradable, and/or toxic organic substances present in the aqueous medium. Efficient physicochemical pretreatments are necessary to modify the structure of the pollutants, by transforming them into less toxic and biodegradable intermediates, allowing then, a biological procedure to complete the degradation of the pollutant load in a sho

The reactivity of phenolic compounds can be drastically affected by the electronic nature of substituents and by their positions in the aromatic ring. In this work, structure effect on the photoreactivity via TiO2 catalysis is studied using several substituted phenols in order to cover a wide variety of electronic effects, ranging from strong electron-donating (activating) to strong electron-withdrawing (deactivating) groups: ---OH, ---OCH3, ---OCH2CH2CH3, ---COOH, ---COH, ---COCH3, ---NO2, ---SO3H, ---CN,

The photodegradation of isoproturon (IP) was performed using TiO2 supported on glass rings in a 1.5 l coaxial rector. After 60 min of phototreatment, IP was completely eliminated and about 80% of dissolved organic carbon (DOC) remained in solution. This efficiency of photodegradation was compared with that using the suspended catalyst in solution and the results indicated that the catalytic activity of TiO2 is not reduced when it is immobilized. The durability of the supported TiO2 was also tested. It was f

A new type of Nafion/Fe structured membrane ensuring faster kinetics, higher efficiency, and mechanical properties has been prepared and will be compared in its performance with the Fe-exchanged commercial Dupont 117 Nafion/Fe membrane during the abatement of model organic compounds. During the casting of the laboratory Nafion sample, the iron ions were introduced directly into the Nafion oligomer solution. This novel laboratory Nafion/Fe was tested as an immobilized catalyst in the degradation of several t

5-amino-6-methyl-2-benzimidazolone (AMBI), used in the manufacture of dyes, was characterised as a biorecalcitrant compound by means of different biodegradability tests. In order to enhance the biodegradability of this important pollutant, the application of Advanced Oxidation Process (AOPs) as a pre-treatment was explored. Some experiments were addressed to find the most efficient AOP. The systems H2O2/hv, TiO2/H2O2/hv, Fe3+/hv, Fe3+/H2O2 and Fe3+/H2O2/hv were compared. The photo-Fenton system was the most

The bacterial inactivation efficiencies of silver metal and oxides and their combinations on textile fabrics was investigated to evaluate the disinfectant action on airborne bacteria. The inactivation performance was seen to depend on the amount of silver on the textile surface. The preparation of the polyester-polyamide Ag-loaded textiles was carried out by RF-plasma and vacuum-UV (V-UV) surface activation followed by chemical reduction of silver salts. The rate of bacterial inactivation by the silver load

he influence of the halogen upon the TiO2 photocatalytic degradation of p-halophenols in water has been investigated. Phenol was used as the reference compound. Compared with its value for phenol, the apparent first-order rate constant of removal, k, was s ...

A novel C-Nafton/Fe-ion structured fabric capable of mediating Orange II decomposition in Fenton-immobilized photoassisted reactions is presented. The catalyst preparation requires the right balance between the amount of the Nafion necessary to protect the C-surface and the minimum encapsulation of the Fe-cluster catalytic sites inside the Nafion to allow the photocatalysis to proceed. The C-Nafion/Fe fabric can be used up to pH 10 under light to photocatalyze the disappearance of Orange II in the presence

The fate of melamine has been studied under UV light irradiation (medium pressure mercury arc) in the presence of TiO2 and H2O2. The increase in the concentration of aromatic and aliphatic photo-products were determined in solution concomitantly with the decrease observed for the melamine concentration. The main intermediate products occurring during photodegradation were identified by liquid chromatography coupled mass spectrometry (LC-MS) with the MS detection in positive and negative ions. The oxidation

Pd nanoparticles (2 nm) stabilized in the micelle core of poly(ethylene oxide)-block-poly(2-vinylpyridine) were studied in partial hydrogenation of 2-butyne-1,4-diol. Both unsupported micelles (0.6 kg Pd/m3) and supported ones on g-Al2O3 (0.042% Pd) showed ...

The degradation of metobromuron (MB), isoproturon (IP), chlortoluron (CT), and chlorbromuron (CB) in heterogeneous photocatalytic solution via TiO2 was studied in detail. The influence of parameters such as TiO2 and herbicide concentration has been investigated and the optimal conditions for the abatement of the herbicides were found. The primary degradation of the herbicides was measured by HPLC analysis. A systematic study of their photodegradation has been made to assess structure–photoreactivity relatio

Sandra Parra Cardona

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Coupling of photocatalytic and biological processes as a contribution to the detoxification of water : catalytic and technological aspects

Structural properties and photoreactivity relationships of substituted phenols in TiO2 suspensions

New integrated photocatalytic-biological flow system using supported TiO2 and fixed bacteria for the mineralization of isoproturon

Synthesis, Testing, and Characterization of a Novel Nafion Membrane with Superior Performance in Photoassisted Immobilized Fenton Catalysis

Photochemical-biological treatment of a real industrial biorecalcitrant wastewater containing 5-amino-6-methyl-2-benzimidazolone

Antibacterial textiles prepared by RF-plasma and vacuum-UV mediated deposition of silver

Photocatalytic degradation of p-halophenols in TiO2aqueous suspensions: halogen effect on removal rate aromatic intermediates and toxicity variations

Abatement of an Azo Dye on Structured C-Nafion/Fe-Ion Surfaces by Photo-Fenton Reactions Leading to Carboxylate Intermediates with a Remarkable Biodegradability Increase of the Treated Solution

Evolution of toxicity during melamine photocatalysis with TiO2 suspensions

Palladium nanoparticles stabilized in block-copolymer micelles for highly selective 2-butyne-1,4-diol partial hydrogenation

Relationships between physicochemical properties and the photoreactivity of four biorecalcitrant phenyl-urea herbicides in aqueous TiO2 suspension

Photoreactivity of Phenolic Compounds in TiO2 Aqueous suspension. Structure Reactivity Relationship Observations.

Structural properties and photoreactivity relationships of different aromatic compounds

Photochemical pre-treatment of two herbicides as a way to improve the biodegradability of their treated solutions

Photocatalytic degradation of para-halophenols in aqueous TiO2 suspensions: Influence of dissolved copper ions

Effect of the Nature of Substituent on the Photoreactivity of the Aromatic Ring

Concentrating vs. non-concentrating reactor for solar photocatalytic degradation of p-nitrotoluene sulfonic acid

Integrated photocatalytic-biological flow system for mineralization of the biorecalcitrant chlorotoluron pesticide

Strategy for the coupling of photochemical and biological flow reactors useful in mineralization of biorecalcitrant industrial pollutants

Effect of the Nature of Substituents in Aromatic Rings on the Biodegradability and Toxicity of Photodegradated Solutions