There is an overview of secondary methods for NOX removal from stationary sources in the first part of master’s thesis. There are well known methods as SCR o SNCR, but also new and experimental ones. An accent is putting on catalytic filtration, especially on cloth filter, which will be used for experiments. An important part of master’s thesis is a project of new experimental unit for experiments with cloth and ceramic catalytic filters as well as with a bit of cloth filtration material. Unit has compact proportions, high-class measurement and control and wide application spectra. Other advantages of this equipment are fast and easy cleaning and installation. This unit, called INTEQ II, can be used in plants or in laboratories. There is prediction model created together with new technology. It enables calculation of efficiency at catalytic filters with variable conditions without many experiments. This model is elaborate and will be finished with dates from measuring. There in only summary of planned experiments in this thesis, because measurements at new unit have not done yet. Experiences with operations at unit INTEQ I were used for proposal of new equipment and for experiments planning.

Research in the field of NOX abatement has grown significantly in the past two decades. The general trend has been to develop new catalysts with complex materials in order to meet the stringent environmental regulations. The master’s thesis deals with the cleaning flue gases through a filter element which is from porous ceramics. There is catalyst implemented for NOx reduction throug the method of selective catalytic reduction in the filter element. There is also description of experimental unit for flue gas cleaning. Part of the thesis is creation of prediction model which allows to predict efficiency reduction in the filtration device operating conditions with some accuracy.

Ce travail de thèse a porte sur l’évaluation de la qualité de l’air sur l’aéroport Paris-Charles- De-Gaulle. L’objectif était d’évaluer l’impact de l’activité aéroportuaire à l’échelle locale et régionale. Cette étude s’est centrée sur les observations à long terme des concentrations des oxydes d’azote (NOx), d’ozone (O3) et des hydrocarbures. Nous avons quantifié la contribution de l’activité aéroportuaire sur les concentrations des NOx observées sur les stations CDG-nord et CDG-sud. Les résultats ont montré que cette contribution était de 18% (12 μ g.m−3) sous un vent du sud et de 47% (25 μ g.m−3) sous un vent du nord. Cette analyse a été réalisée à partir de 3 ans de mesures (2005-2007). Les concentrations des NOx ont également été analysées à l’aide d’un modèle neuronal. Ce modèle a été construit pour estimer les concentrations des NOx en fonction de paramètres météorologiques (direction du vent, vitesse du vent, température, hauteur de la couche limite) et temporels (jour de l’année, heure du jour et la différence entre les jours de la semaine et du week-end). Le modèle a permis d’estimer les concentrations des NOx pour des scénarios ponctuels. Des campagnes de mesures ciblées sur les hydrocarbures ont été mises en oeuvre au cours de cette thèse. Elles ont permis de caractériser la spéciation des hydrocarbures émis par les moteurs d’avion. Les résultats ont montré que cette spéciation était similaire de celle observée pour les véhicules diesel. Ceci ne permet pas d’établir clairement un profil caractéristique permettant de distinguer les émissions des avions de celles de véhicules. La spéciation des hydrocarbures sur la plate-forme a également été évaluée. Les résultats ont montré que la spéciation des hydrocarbures observée sur la plate-forme est comparable à celle observée en milieu urbain et dans d’autres milieux aéroportuaires. Par ailleurs, les concentrations moyennes observées étaient typiquement de l’ordre de celles observées dans une atmosphère urbaine. L’estimation de l’impact des activités aéroportuaires à l’échelle régionale a fait l’objet d’une étude préliminaire à l’aide d’un modèle de chimie-transport, CHIMERE. Cette étude a permis d’évaluer l’étendue spatiale de l’impact de l’activité aéroportuaire pour deux épisodes. Ces épisodes correspondent à un épisode de pollution estival à l’ozone et hivernal au NO2. Les simulations ont indiqué une contribution inférieure à 5μ g.m−3 à une quinzaine de kilomètres sous le vent de l’aéroport / The work presented here deals with the evaluation of air quality at Paris-Charles-de-Gaulle airport. The objective was to evaluate the local and regional impact of airport activity. This study is centered on long term measurements of nitrogen oxides (NOx), ozone (O3) and hydrocarbons concentrations. We calculated the contribution of airport activity to NOx concentrations in north and south stations. Results showed this contribution was 18% (12 μ g.m−3) from southern wind and 47 % (25 μ g.m−3) from northern wind. This analysis had been performed from 3 years data (2005-2007). NOx concentrations had been also analyzed with a neuronal model. This model was built in order to estimate concentrations according to meteorological (wind direction, wind velocity, temperature, boundary layers) and temporal parameters (day, hour, difference between week-day and week-end). The neuronal model allowed to estimate NOx concentrations for punctual scenarios. Field campaigns targeting hydrocarbons were conducted during this thesis. The speciation of hydrocarbons emitted by engine aircraft was characterized. These results showed engine aircraft hydrocarbon speciation was similar to motor diesel hydrocarbon speciation. This does not allow for the clear establishment of a characteristic profile that differentiates aircraft emissions from those of vehicles. Hydrocarbon speciation observed at the airport was also evaluated. Results showed that the hydrocarbon speciation detected at the airport was comparable to that observed within an urban environment as well as at other airports. Moreover, average concentrations were akin to those observed within an urban environment. The estimation of regional impact of airport activity was preliminary studied with a chemicaltransport model, CHIMERE. This study permitted the evaluation of the spatial extent of the impact of airport activity for two episodes. These episodes correspond to summer pollution by ozone and winter pollution by NO2. Simulations showed the contribution downwind of the airport was lower than 5 μ g.m−3 for 15 km

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The mechanism of RAPRENOx reactions - RAPid REduction of Nitrogen Oxides using Isocyanic acid - proposed by Robert A. Perry1 in an attempt to help control the emission of nitrogen oxides pollutant into the atmosphere, has been re-investigated theoretically. The study of reaction mechanisms was carried out using Chemist software2. All mathematically possible elementary steps have been evaluated and the chemically reasonable ones have been considered to propose new sets of reaction mechanisms. Density Functional Theory (B3LYP/6-31 G**) calculations using Gaussian 983 were made in order to study the relative energies of all species and to predict the energy barrier of each elementary step. As a consequence of our study, there are two more sets of reaction mechanisms (in addition to Perry’s mechanism), that could be possible for the propagation step of RAPRENOx process.

Yes / In this work, the effect of the nanosized CZA2 (cerium-zirconium-aluminium) on the performance and emissions in a two- cylinder indirect injection (IDI) diesel engine, was studied. CZA2 was dispersed in diesel (D100) and waste cooking oil and tallow origin biodiesel-diesel blends (B10, B20, B30) and tested at different engine loads and constant speed. The nanocatalyst (CZA2) increased the brake specific fuel consumption (BSFC) and decreased the brake thermal efficiency (BTE, %) of all tested fuels, at all loads, except B20 at the lowest load. CZA2 reduced nitrogen oxides (NOx) from D100 at low and high engine loads, as well as carbon monoxide (CO) and unburned hydrocarbons (HC) at medium and high tested loads. The dispersion of CZA2 promoted the combustion of the biodiesel blends by almost eliminating HC while reducing NOx and CO emissions at various loads. Thermogravimetric analysis (TGA) coupled with Attenuated Total Reflectance- Fourier Transform Infrared (ATR-FTIR) spectroscopy revealed that the addition of CZA2 in diesel and biodiesel under pyrolysis and oxidation conditions resulted in the presence of saturated species like ketones and final oxidation products such as CO2, supporting their improved combustion and emissions’ reduction in the engine tests.

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The use of Silicon Carbide Field Effect Transistor (SiC-FET) sensors in cyclic operation is a proven way to quantify different gases. The standard workflow involves extracting shape-defining features such as averages and slopes of the sensor signal. This work’s main goal is to verify if frequency modulation can be used to simultaneously quantify Nitric Oxide (NO), Nitrogen Dioxide (NO2) and Ammonia (NH3). Linear models were chosen, namely: Ordinary Least Squares (OLS), Principal Components Regression (PCR), Partial Least Squares Regression (PLSR) and Ridge regression. Results indicate that these models fail to predict concentrations completely for every gas. Analysis indicates that the features are not linear in terms of concentrations. This work is concluded by recommending a few other alternatives before discarding frequency cycling completely: non-parametric models of regression and different frequency regime, namely the use of triangular waves in future experiments.

Energetic materials (i.e., explosives, propellants, and pyrotechnics) have been used for centuries in a wide variety of applications that include celebratory firework displays, the demolition of ‘immovable’ structures, mining resources from the earth’s crust, launching humans into outer space, and propelling munitions across the battlefield. Many different scientific and engineering domains have found unique value in their characteristic release of significant heat and pressure. While the rate at which energetic materials react is often dependent on the source of initiation, surrounding thermodynamic conditions, and formulation sensitivity, many applications aim for a controlled combustion process to produce large amounts of work output – solid and liquid rocket motors and gun-launched projectiles are a few key examples. Other energetic material systems are often inadvertently exposed to thermal insults, which can result in similar combustion behavior. To accurately model these systems, it is important to have a fundamental understanding of the chemical kinetics that control various aspects of the combustion process (e.g., changes in temperature (T), pressure (P), and species mole fractions (X)). Detailed chemical kinetic models are often used to understand and subsequently predict such behavior. Understanding the gas-phase reaction kinetics of energetic materials is essential when trying to predict critical performance parameters such as flame speeds, temperature and pressure profiles, and heat flux between material phases. These parameters can have significant impact on predictions of system-level performance (e.g., the specific impulse of solid rocket motors, propellant burn rates in projectile systems, and munition responses to thermal insult and extended temperature cycling). While the gas-phase reaction kinetics of energetic material combustion were heavily studied from the late 1970’s to the early 2000’s, research efforts beyond this time frame have primarily focused on condensed-phase chemistry as it is thought to be less understood. Over the past two decades, however, there have been significant advances in our understanding of small molecule reactions that have not yet been accounted for in many energetic material models. One such example are chemically termolecular reactions – a new class of phenomenological reactions that have not yet been considered for inclusion in any energetic material kinetic models. Recent studies have indicated that chemically termolecular reactions, mediated through ephemeral collision complexes, have significant impact on the global kinetics of certain combustion systems. This discovery has since prompted the question of which systems are significantly influenced by chemically termolecular reactions and should therefore account for their presence in gas-phase phenomenological models. Although a select number of systems have already been investigated, such as flame speed and ignition delay predictions in common hydrocarbon combustion scenarios, the influence of chemically termolecular reactions on the kinetics of energetic materials has not yet been explored. As an initial investigation into energetic materials, a case study for RDX was performed, for which abundant computational and experimental data are available. To aid in assessing the impact of chemically termolecular reactions, for which almost no data are available, this study leveraged an automated procedure to identify and estimate rate constants for potential chemically termolecular reactions based exclusively on data available for related reactions. Four detailed kinetics models for RDX were independently screened for potential chemically termolecular reactions. Model predictions including these chemically termolecular reactions revealed that they have significant potential impact on profiles of major species, radicals, and temperatures. T he analysis pinpointed ∼20-40 chemically termolecular reactions, out of the thousands of possibilities, estimated to have the largest impact. These reactions, including many mediated by ephemeral HNO** and NNH** complexes, are therefore worthwhile candidates for more accurate quantification via master equation calculations. More generally, just as the importance of including chemically termolecular reactions in hydrocarbon combustion models is becoming recognized, the present results show compelling evidence for the need for their inclusion in energetic material models as well. The investigation into chemically termolecular reactions yielded a secondary conclusion based on the observed influence of the small molecule C/H/N/O chemistry on overall predictions of energetic material combustion – updating the small molecule chemistry in RDX models produced significant changes to predictions of major species and temperature, suggesting that the development of a comprehensive gas-phase energetic material combustion model would be of great value and have broad utility as a foundational model for a great variety of C/H/N/O energetic materials. To begin developing such a model, all small molecule chemistry in current kinetic models was reviewed with the intent of identifying a sub-model in need of revisions and subsequently addressing its uncertainties using targeted experiments to improve overall predictions. The ammonia sub-model was selected as it is both highly uncertain and highly influential in many energetic material models. Ammonia (NH₃) has garnered substantial attention in recent years due to its importance across many scientific domains – including its potential use as a carbon-free fuel and long-term energy storage option, its use in reducing combustion-generated nitrogen oxide emissions, its role as a decomposition fragment of many energetic materials, and its presence as an important impurity during biofuel and biomass combustion that can affect overall system kinetics, among others. Yet, it is generally recognized that there are still significant gaps in the present understanding of ammonia kinetics -– in both experimental data sets and sub-models within the overall ammonia kinetic mechanism. For example, most experimental studies of ammonia oxidation have used molecular oxygen as the primary or sole oxidizer. While large mole fractions of molecular oxygen are encountered in many combustion scenarios, there are select systems where ammonia is more likely to be oxidized via nitrogen-containing species (e.g. N₂O and NO₂) and, more generally, there are relatively untested reaction sets that would be accentuated in such conditions. To address these gaps in available experimental data needed for the validation of ammonia kinetics models, jet-stirred reactor experiments were performed for mixtures of NH₃/N₂O/N₂ over an intermediate temperature range (850-1180 K). In these experiments, the mole fractions of NH₃, N₂O, and NO were measured using a combination of gas chromatography, chemiluminescence, electrochemical detection, and infrared absorption – where agreement among the different diagnostics (within 3% for N₂O and 7% for NO) ensured high confidence in the experimental measurements. Comparison of the experimental results and model predictions suggested deficiencies in commonly used models for nitrogen kinetics. Various modeling analyses pointed to the central role of the N₂O + NH₂ = N₂H₂ + NO reaction, on which recent kinetic models all rely on the same rate constant estimate that appears to have not been tested in previous validation data sets for NH₃ kinetics. A second set of jet-stirred reactor experiments were performed for mixtures of NH₃/NO₂/O₂/N₂ over a slightly different temperature range (700–1100 K). Agreement among different diagnostics (≤7% for NO₂ and ≤4% for NH₃) and excellent experimental repeatability confirmed high confidence in all species measurements. Measured mole fractions were compared to predictions from five recently developed kinetic models using flux analysis and uncertainty-weighted kinetic sensitivity analysis, both of which pointed to the importance of reactions involving H₂NO that are both influential in this system and highly uncertain. The measurements from the jet-stirred reactor experiments presented here were combined with comprehensive sets of experimental data and high-level theoretical kinetics calculations using the MultiScale Informatics (MSI) approach to unravel the large uncertainties present in current NH3 oxidation kinetic sub-models. Emphasis was placed on NH₃ oxidation via nitrogen-containing species as this chemistry has been shown to accentuate influential reactions (e.g., the NO₂+NH₂ and NH₂+NO reactions) that are known to be important during the combustion of many energetic materials (e.g., AN, ADN, and AP). The resulting MSI model accurately predicted nearly all of the experimental and theoretical target data within estimated or reported uncertainties. Additional predictions of two NH₃/NO₂ validation data sets, which were not included in the MSI framework, demonstrated its ability to accurately extrapolate predictions to untested T/P/X conditions, indicating that the converged MSI model demonstrates truly predictive behavior. The MSI NH₃ oxidation model presented here should be considered for inclusion in many energetic material models as the NH₃/NOₓ kinetic system is known to be important to the combustion of various propellant and explosive formulations. This sub-model will help to form a foundational gas-phase kinetic model relevant to many different energetic materials, including those that contain inorganic additives for increased energy density and blast effects.