Do FeO/TiO heterojunctions improve the wastewater disinfection process?

This work examines the photocatalytic capacity of FeO-TiO catalysts for inactivating Enterococcus faecalis in water and compares it to a peroxide-assisted process. The influence of HO, PMS, pH, and temperature is assessed. Material stability and free radical species involved in disinfection are also evaluated.

Photocatalytic Synthesis of Hydrogen Peroxide from Molecular Oxygen and Water.

Hydrogen peroxide is a powerful and green oxidant that allows for the oxidation of a wide span of organic and inorganic substrates in liquid media under mild reaction conditions, and forms only molecular water and oxygen as end products. Hydrogen peroxide is therefore used in a wide range of applications, for which the well-documented and established anthraquinone autoxidation process is by far the dominating production method at the industrial scale. As this method is highly energy consuming and environmentally costly, the search for more sustainable synthesis methods is of high interest.

Irradiance-Controlled Photoassisted Synthesis of Sub-Nanometre Sized Ruthenium Nanoparticles as Co-Catalyst for TiO in Photocatalytic Reactions.

Photoassisted synthesis is as a highly appealing green procedure for controlled decoration of semiconductor catalysts with co-catalyst nanoparticles, which can be carried out without the concourse of elevated temperatures, external chemical reducing agents or applied bias potential and in a simple slurry reactor. The aim of this study is to evaluate the control that such a photoassisted method can exert on the properties of ruthenium nanoparticles supported on TiO by means of the variation of the incident irradiance and hence of the photodeposition rate. For that purpose, different Ru/TiO systems with the same metal load have been prepared under varying irradiance and characterized by means of elemental analysis, transmission electron microscopy and X-ray photoelectron spectroscopy.

Ti-Modified LaFeO/β-SiC Alveolar Foams as Immobilized Dual Catalysts with Combined Photo-Fenton and Photocatalytic Activity.

Ti-modified LaFeO/β-SiC alveolar foams were used as immobilized, highly robust dual catalysts with combined photocatalytic wet peroxide oxidation and photocatalytic activity under UV-A light. They were prepared by incipient wetness impregnation of a β-SiC foam support, by implementing a sol-gel Pechini synthesis at the foam surface in the presence of dried amorphous sol-gel titania as a titanium source. The physicochemical and catalytic features suggest the stabilization at the foam surface of a substituted LaTiFeO catalyst analogous to its powdery counterpart.

Activity enhancement pathways in LaFeO@TiO heterojunction photocatalysts for visible and solar light driven degradation of myclobutanil pesticide in water.

LaFeO@TiO heterojunction composites with a core-shell porous structure and LaFeO contents in the 2.5-25 wt.% range have been synthesized via consecutive sol-gel syntheses and tested for the photocatalytic oxidation of the myclobutanil pesticide in water under solar light and pure visible light.

Body Mass Index as a Prognostic Factor in Liver Transplantation.

Objective: Obesity is one of the main growing epidemics of the last century and is responsible for many deaths worldwide. The aim of this study is to analyze the impact of the body mass index (BMI) of the recipient on survival and morbidity after liver transplantation (LT).

Material And Methods: We conducted a retrospective cohort study of all transplanted recipients in a third-level hospital between 2006 and 2018.

Coating-free TiO@β-SiC alveolar foams as a ready-to-use composite photocatalyst with tunable adsorption properties for water treatment.

Coating-free TiO@β-SiC photocatalytic composite foams gathered within a ready-to-use shell/core alveolar medium the photocatalytically active TiO phase and the β-SiC foam structure were prepared a multi-step shape memory synthesis (SMS) replica method. They were fabricated following a sequential two-step carburization approach, in which an external TiC skin was synthesized at the surface of a β-SiC skeleton foam obtained from a pre-shaped polyurethane foam during a first carburization step. The adsorption behaviour of the shell/core TiO@β-SiC composite foams towards the Diuron pollutant in water was tuned by submitting the carbide foams to a final calcination treatment within the 550-700 °C temperature range.

Ferrite Materials for Photoassisted Environmental and Solar Fuels Applications.

Ferrites are a large class of oxides containing Fe and at least another metal cation that have been investigated for and applied to a wide variety of fields ranging from mature technologies like circuitry, permanent magnets, magnetic recording and microwave devices to the most recent developments in areas like bioimaging, gas sensing and photocatalysis. In the last respect, although ferrites have been less studied than other types of semiconductors, they present interesting properties such as visible light absorption, tuneable optoelectronic properties and high chemical and photochemical stability. The versatility of their chemical composition and of their crystallographic structure opened a playground for developing new catalysts with enhanced efficiency.

Evaluation of photoassisted treatments for norfloxacin removal in water using mesoporous FeO-TiO materials.

We report the synthesis of mesoporous TiO and mesoporous FeO-TiO catalysts by using a structure-directing-surfactant method, their characterization and their employment as photocatalysts for norfloxacin degradation in aqueous solution. The main findings show that in the presence of both O and HO, Fe-containing mesoporous titania (FeO-TiO), with iron percentages between 1 and 3 wt%, exhibited norfloxacin degradation rates more than 60% greater than otherwise identical mesoporous titania without iron. Furthermore, the activity of the mesoporous composite catalysts also exceeds that of titania when illuminated with 405 nm light-emitting diodes.

Photoactive ZnO Materials for Solar Light-Induced CuO-ZnO Catalyst Preparation.

In this work, the solar light-induced redox photoactivity of ZnO semiconductor material was used to prepare CuO-ZnO composite catalysts at room temperature with a control of the chemical state of the copper oxide phase. Cu₂O-ZnO and CuO-ZnO composite catalysts were prepared by using Cu(acac)₂ in tetrahydrofuran-water and Cu(NO₃)₂ in water as metallic precursor, respectively. Prior to the implementation of the photon-assisted synthesis method, the most efficient photoactive ZnO material was selected from among different ZnO materials prepared by the low temperature polyol and precipitation methods with carbonates and carbamates as precipitation agents.

Improving the Fenton process by visible LED irradiation.

The effect of irradiation with visible light-emitting diode (LED) light on the efficiency of Fenton oxidation is investigated using phenol as the target compound (100 mg/L). The HO dose and temperature are tested as operating variables with the aim of minimizing consumption of the reagents. At 50 °C, 10 mg/L Fe, and 60 % of the stoichiometric HO amount, phenol was completely oxidized into CO, HO, and short chain organic acids, with oxalic acid completely degraded.

Effect of water composition on the photocatalytic removal of pesticides with different TiO2 catalysts.

The objective of this work is double-firstly to explore the photocatalytic efficiency of five different commercial TiO2 catalysts in the photodegradation of a mixture of pesticides classified by the EU as priority pollutants and secondly to analyze the correlation between their physicochemical properties and the inhibition of the studied photocatalytic process when natural water was employed. Photocatalytic efficiencies when ultrapure water was used seem to point out that surface area was not a prerequisite for the photodegradation of the selected mixture of pesticides. On the other hand, significant differences in total organic carbon (TOC) conversions were obtained with the two studied water compositions.

[Promoter hypermethylation gene patterns in gynecological tumors].

Background And Objective: Gene silencing mediated by the aberrant methylation of the promoter region of DNA is involved in the inactivation of genes implicated in various metabolic pathways. Such a gene hypermethylation has become a useful molecular marker for the diagnosis, treatment and follow-up of cancer patients. Our objective is to analyze the patterns of gene hypermethylation in patients with gynecological tumors.