Quantitative kinetic and physical phase partitioning models of secondary organic aerosol (SOA) formation resulting from the reactions of aromatic species were integrated into a mechanism for gas-phase reactions. Using the resulting model, analyses of the sensitivity of SOA formation to several parameters (e.g., VOC/NOx ratio, rate parameters) were performed. Results indicated that aerosol yield (SOA formed per amount of hydrocarbons reacted) depends on the extent of conversion of parent hydrocarbons, partitioning coefficient, initial aerosol mass concentration, and rate parameters. On the basis of the sensitivity studies, models for SOA yield were developed for 11 aromatic compounds. Comparison of the results from current SOA models to the results from this study suggests that mechanisms describing SOA formation from aromatic species must incorporate the reactions of reactive intermediates.

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Photocatalytic oxidation purposes an economical and environmental friendly process to remove benzene from indoor air pollution. However, the process efficiency is primarily dependent on catalytic-film. The main purpose of this study is to synthesize pre-vulcanized latex impregnated with TiO 2 (PVL-TiO 2 thin film) from natural rubber to be used in photo-catalytic oxidation for benzene removal in a reactor. PVL-TiO 2 thin films were synthesized for 3 different dosages of TiO 2 , which were 5%, 15%, and 25% The outcome of this study offers the new application of modified natural rubber in terms of environmental and health care protection. Morphology of the synthesized films was analyzed by SEM. The results showed that TiO 2 particles could be well dispersed all over the surface of the film, in which the best distribution could be found for the PVL-TiO 2 15% thin film. Tensile stress of the films was analyzed using ASTM D412. Results showed that the stress of the films got higher with the increasing amount of TiO 2 content. This indicates that TiO 2 strengthened the PVL-TiO 2 film because the uniformly distribution of TiO 2 on the inner surface increased the strength of the film. The decomposition of PVL and PVL-TiO 2 thin films was analyzed using thermo gravimetric analysis. The maximum weight loss rates in the range of 1.536-1.145 wt %/ C attained at between 380 -382 C TiO 2 particles enhanced thermal stability of PVL-TiO 2 thin films due to the high decomposition temperature of its properties and also acted as barrier for the heat transfer of the films. Specific surface area (SSA) of the films was analyzed using Brunauer-Emmett-Teller. Specific surface area increased as the increasing content of TiO 2 , which corresponded to the morphology analysis by SEM. The analysis of chemical functional group of thin films was performed using ATR-FTIR. The results of Crystal identification using XRD clearly showed good attachment of rutile TiO 2 on the films. Finally, results of absorbance spectrums and band gap energy showed that PVL not only peg TiO 2 particles but also reducing band gap energy which induced by S and ZnO. Therefore, PVL-TiO 2 thin films could be used under visible light condition. The films were then used in the study of benzene removal in annular reactor. The highest removal efficiency (83%)for the PVL-TiO 2 15% thin film was obtained. Comparing to the maximum removal efficiency for PVL film (28%), roughly 60% increase in efficiency was achieved. The PCO kinetics were well fit by a first order Langmuir-Hinshelwood model. The calculation of oxidation rate and percentage of residual intermediates indicated that accumulation of residual intermediates can occur on the active site and the gas phase, resulting in increasing of residual intermediates. The successful synthesis of PVL-TiO 2 thin film provides new opportunity to use natural rubber in terms of environmental and health care protection.

Quantitative kinetic and physical phase partitioning models of secondary organic aerosol (SOA) formation resulting from the reactions of lumped aromatic species were integrated into a state of the art mechanism for gas-phase reactions (SAPRC). Aromatic and aerosol precursor species were aggregated based on their rate of reaction with OH radicals. Model parameters for the lumped model species were estimated based on the properties of individual compounds making up the lumped parameters. The model was applied to estimate the contribution of aromatic precursors to the formation of SOA in Houston, TX.

Secondary Organic Aerosol (SOA) formation due to precursor emissions from anthropogenic sources in the Houston/Galveston (HG) area was estimated by multiplying the anthropogenic emissions of SOA precursors by fractional aerosol coefficients (FAC). The analysis indicated that area and nonroad mobile sources contributed 56% of the aerosol precursor emissions, while mobile and point sources contributed 27% and 16%, respectively. However, due to high SOA yields of the precursors emitted by point sources, especially emissions of terpenes from pulp and paper processing and emissions of aromatics, point source emissions resulted in 53% of the projected SOA from anthropogenic sources in the HoustonGalveston (HG) area. Estimated SOA formation rates were consistent with average concentrations of particle-phase organic carbon in the Houston-Galveston area.