Search results for "VOCs."
showing 10 items of 29 documents
Exploring the photothermo-catalytic performance of brookite tio2-ceo2 composites
2020
The thermocatalytic, photocatalytic and photothermo-catalytic oxidation of some volatile organic compounds (VOCs), 2-propanol, ethanol and toluene, was investigated over brookite TiO2-CeO2 composites. The multi-catalytic approach based on the synergistic effect between solar photocatalysis and thermocatalysis led to the considerable decrease in the conversion temperatures of the organic compounds. In particular, in the photothermo-catalytic runs, for the most active samples (TiO2-3 wt% CeO2 and TiO2-5 wt% CeO2), the temperature at which 90% of VOC conversion occurred was about 60 °
Ferric sludge derived from the process of water purification as an efficient catalyst and/or support for the removal of volatile organic compounds
2019
Ferric chloride solutions are used as coagulants or flocculants in water treatment operations for human consumption. This treatment produces large amounts of clay-type solids formed mainly of montmorillonite with iron oxides and humic substances. This ferric sludge can be used as an efficient catalyst for the removal of volatile organic compounds (VOCs) by total oxidation. This waste isolated in the purification process has been activated by calcinations in air, characterized by several physicochemical techniques and employed as a catalyst for the removal by total oxidation of representative VOCs: toluene, propane and mixtures of toluene/propane with or without water. This ferric sludge has…
Modeling of a continuous photocatalytic reactor for isovaleraldehyde oxidation: Effect of different operating parameters and chemical degradation pat…
2013
International audience; An investigation of isovaleraldehyde (ISOV) photocatalytic oxidation was conducted at initial concentrations ranging from 25 to 150 mg/m3 and different relative humidities (5-90% RH) in order to characterize the process performances close to indoor air conditions. Experiments were carried out in two different reactors: cylinder and flat-plate photoreactor (planar reactor) at different air gap (20-60 mm) and gas residence times (0.67-5.0 s). A plug flow reactor system was developed in order to perform kinetic studies of (i) isovaleraldehyde removal, (ii) selectivity of CO2, (iii) byproducts formation and removal. It appears that ISOV removal efficiencies increased wit…
Use of sequentially inoculation of Saccharomyces cerevisiae and Hanseniaspora uvarum strains isolated from honey by-products to improve and stabilize…
2022
Mead is a beverage produced by alcoholic fermentation of honey-must. The starter yeasts that are commonly used for the alcoholic fermentation of honey-must are oenological Saccharomyces cerevisiae strains. The objective of the present work was, for the first time, to apply yeasts of honey by-products origin to evaluate the influences the taste-olfactory attributes of mead. For this purpose, three experimental productions were set up, which included: (i) single inoculation of S. cerevisiae; (ii) single inoculation of Hanseniaspora uvarum; (iii) sequential inoculation of H. uvarum/S. cerevisiae. Two control trials were performed, using a commercial strain of S. cerevisiae of oenological origi…
Low temperature total oxidation of toluene by bimetallic Au–Ir catalysts
2017
9 Figuras.- 3 Tablas.- Información suplementaria disponible en la página web del editor
Total oxidation of VOCs on mesoporous iron oxide catalysts: Soft chemistry route versus hard template method
2016
9 figures, 3 tables.-- Supplemantary information available
Effect of solid waste landfill organic pollutants on groundwater in three areas of Sicily (Italy) characterized by different vulnerability
2017
The aim of this study was to obtain information on the presence and levels of hazardous organic pollutants in groundwater located close to solid waste landfills. Eighty-two environmental contaminants, including 16 polycyclic aromatic hydrocarbons (PAHs), 20 volatile organic compounds (VOCs), 29 polychlorinated biphenyls (PCBs), 7 dioxins (polychlorinated dibenzo-p-dioxins, PCDDs) and 10 furans (polychlorinated dibenzofurans, PCDFs) were monitored in areas characterised by different geological environments surrounding three municipal solid waste landfills (Palermo, Siculiana and Ragusa) in Sicily (Italy) in three sampling campaigns. The total concentrations of the 16 PAHs were always below t…
Chemical ecology of Bagrada hilaris (Burmeister) (Heteroptera: Pentatomidae): intraspecific and interspecific chemical cues
2020
The chemical ecology of Heteroptera insects is determined by a wide array of chemical signals (semiochemicals) that drive their behavior at intra- and inter-specific level. Intraspecific semiochemicals are called pheromones, interspecific chemicals are named allelochemicals. In the case of stink bugs, sex-pheromones and aggregation pheromone are produced by adult males. Furthermore, phytophagous stink bugs exploit chemical cues emitted from plants to find a suitable food and oviposition source. The semiochemicals involved in this process are named kairomones and are generally formed by specific blend or key odorants emitted from host plant. The chemical ecology of the phytophagous Pentatomi…
The behavioral responses of the egg parasitoid Ooencyrtus telenomicida to semiochemicals from first and second trophic level
2009
In this study the responses of females of the egg parasitoid Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae) to volatile and contact chemicals from its host Nezara viridula (L.) (Heteroptera: Pentatomidae) and from host plant Solanum lycopersicum L. were investigated in a Y-tube olfactometer and in open arena. Our results in the Y-tube olfactometer tests showed that: (1) female wasps were attracted to volatiles from adult host virgin male and to volatiles from a host mated female, showing a clear preference for the volatiles emitted from the former; volatiles from host virgin females did not attract O. telenomicida females; (2) only volatiles produced by host-damaged plant com…
Distribution of Volatile Organic Compounds in Sicilian groundwaters analysed by Head Space Solid Phase Micro Extraction coupled with Gas Chromatograp…
2008
This work presents the results of an assessment of the existence and concentration of 13 volatile organic compounds (VOCs) in groundwaters from 14 hydrological basins in Sicily (25,710 km2). On the basis of hydrological, hydrogeochemical and geological studies, 324 sampling points were selected. All groundwater sampled were collected twice, from October to December 2004 and from February to May 2005, and were analysed to determine the concentration and spatial distribution of the VOCs in the aquifers. The need to analyze a large number of samples in a short space of time so as to obtain quantitative analyses in trace concentration levels spurred us to create a new analytical method, both si…