Assessment of VOCs Material/Air Exchanges of Building Products Using the DOSEC®-SPME Method

ACTInternational audienceUsing low emissive materials in building is an effective way to reduce indoor concentrations of pollutants such as VOCs. Material emissions are assessed by the ISO 16000-9 standard. This procedure is time-consuming and is not suitable for on-site measurements. This work aimed in assessing an alternative method, DOSEC\textregistered-SPME, for simple measurements. To validate it, emissions of 30 materials were characterized by both ISO 16000-9 and DOSEC\textregistered-SPME. A first correlation was found between the two methods for formaldehyde emissions of raw materials. This encouraging result allows considering the development of new decision making tools for the selection of healthy building materials

: Advanced functional cellular materials bearing multiscale porosity

With this mini review we show through the sol-gel and emulsion-based Integrative Chemistry how it is possible to trigger materials dimensionality and beyond their functionalities when reaching enhanced applications. In here we focus on 3D macrocellular monolithic foams bearing hierarchical porosities and applications thereof. We first depict the general background of emulsions focusing on concentrated ones, acting as soft templates for the design of PolyHIPE foams, HIPE being the acronym of High Internal Phase Emulsions while encompassing both sol-gel and polymer chemistry. Secondly we extend this approach toward the design of hybrid organic-inorganic foams, labeled Organo-Si(HIPE), where photonics and heterogeneous catalysis applications are addressed. In a third section we show how inorganic Si(HIPE) matrices can be employed as sacrificial hard templates for the generation carbonaceous foams, labeled Carbon(HIPE). These foams being conductive we show applications when employed as electrodes for Li-S battery and as hosts for Li(BH4)-based hydrogen storage

Integrative Sol-Gel Chemistry

Integrative chemistry is the link between the notions of “complexity in chemistry” and the bio-inspired integrative synthesis. This chapter relies on this vein of integrative chemistry, while dealing with sol-gel chemistry. Through the sol–gel-based integrative chemistry, it shows how it is possible to trigger materials dimensionality and beyond their functionalities when reaching enhanced applications. Thereby it selectively proposes the morphosyntheses of discrete objects, 1D materials (fibers), 2D arrays (films), and 3D macrocellular foams bearing hierarchical porosities (monoliths). The chapter discusses in detail how integrative chemistry allows fine-tuning of material shapes and dimensions while offering enhanced applications. Considering the shaping modes, it also deals with how the integrative chemistry allows positioning the chemical reactors within the geometric spaces, with specific competence appearing as a novel paradigm with regard to traditional sol-gel chemistry

Comparison of kinetics of acetone, heptane and toluene photocatalyticmineralization over TiO2microfibers and Quartzel®mats

The kinetic parameters for VOCs (acetone, toluene, heptane) mineralization of lab-extruded pure TiO2fibers prepared under easily scalable conditions were compared with those of a commercial photo-catalytic media from Saint-Gobain, Quartzel®, under identical conditions. A flow-through recirculatingreactor loop with variable LEDs irradiation at 365 nm was specially designed. All the experiments werecarried out in a continuous recycle mode. Both types of fibers were very efficient for acetone and hep-tane mineralization. At 20% relative humidity (RH), the reaction rates were higher with the commercialmedia, whereas at 60% RH the catalysts displayed equal activity for acetone conversion. Toluene min-eralization was much faster on these lab-made fibers than on Quarztel®, which was more sensitiveto poisoning by reaction by-products. At 20% relative humidity, with the lab-made TiO2fibers, typicalquantum efficiencies were, respectively, 0.0106 and 0.0027 for acetone and heptane (100 ppmV initialconcentration) and 0.0024 for toluene (200 ppmV initial concentration) while these quantum efficiencieswere 0.0358, 0.0133 and 0.0011 with expanded Quartzel fibers under the same conditions. These resultsevidence a clear difference in the VOCs, water and polar by-products adsorption between these two kindsof fibers.These newly developed fibers can be produced at an industrial scale with a proven efficiency for VOCsdegradation and mineralization. Since they are less sensitive to humidity than the commercial fibers,they could be most useful under actual ambient air conditions. These fibers present a good alternative toother commercially available photocatalytic media for gas phase purification

Comparison of kinetics of acetone, heptane and toluene photocatalytic mineralization over TiO2 microfibers and Quartzel® mats

International audienceThe kinetic parameters for VOCs (acetone, toluene, heptane) mineralization of lab-extruded pure TiO2fibers prepared under easily scalable conditions were compared with those of a commercial photo-catalytic media from Saint-Gobain, Quartzel®, under identical conditions. A flow-through recirculatingreactor loop with variable LEDs irradiation at 365 nm was specially designed. All the experiments werecarried out in a continuous recycle mode. Both types of fibers were very efficient for acetone and hep-tane mineralization. At 20% relative humidity (RH), the reaction rates were higher with the commercialmedia, whereas at 60% RH the catalysts displayed equal activity for acetone conversion. Toluene min-eralization was much faster on these lab-made fibers than on Quarztel®, which was more sensitiveto poisoning by reaction by-products. At 20% relative humidity, with the lab-made TiO2fibers, typicalquantum efficiencies were, respectively, 0.0106 and 0.0027 for acetone and heptane (100 ppmV initialconcentration) and 0.0024 for toluene (200 ppmV initial concentration) while these quantum efficiencieswere 0.0358, 0.0133 and 0.0011 with expanded Quartzel fibers under the same conditions. These resultsevidence a clear difference in the VOCs, water and polar by-products adsorption between these two kindsof fibers.These newly developed fibers can be produced at an industrial scale with a proven efficiency for VOCsdegradation and mineralization. Since they are less sensitive to humidity than the commercial fibers,they could be most useful under actual ambient air conditions. These fibers present a good alternative toother commercially available photocatalytic media for gas phase purification

TiO2 macroscopic fibers bearing outstanding photocatalytic properties obtained through an integrative chemistry-based scale-up semi-industrial process

In here we depict the morphogenesis and associated properties of TiO2-based macroscopic fibers designed for the photodecomposition of volatile organic compounds (VOC). We employed a continuous industrially scalable extrusion-based process making the use of hybrid sols of amorphous titania nanoparticles, polyvinyl alcohol (PVA) and occasionally latex nanoparticles. This process allowed for the continuous generation of hybrid TiO2/latex/PVA or TiO2/PVA macroscopic fibers. Upon thermal treatment, biphasic porous fibers are obtained containing the anatase phase of TiO2 with 10-15% of brookite These fibers, which can be manufactured under several hundred meter of length, are offering significantly improved phototocatalytic efficiency now comparable to the commercial Quartzel®PCO photocatalyst for gas-phase acetone mineralization

DOSEC-SPME : a new technique to assess the VOC emission of material

International audienc

New methodology for determination of formaldehyde sorption rate constants for selected building materials of indoor surfaces

International audienc

New methodology for determination of formaldehyde sorption rate constants for selected building materials of indoor surfaces

International audienc