The selective catalytic reduction (SCR) of nitric oxide (NO) with ammonia over vanadia-based (V2O5-WO3/TiO2) and pillared interlayer clay-based (V2O5/Ti-PILC) monolithic honeycomb catalysts using a laboratory laminar-flow reactor was investigated. The experiments used a number of gas compositions to simulate different combustion gases. A Fourier transform infrared (FTIR) spectrometer was used to determine the concentrations of the product species. The major products were nitric oxide (NO), ammonia (NH3), nitrous oxide (N2O), and nitrogen dioxide (NO2). The aim was to delineate the effect of various parameters including reaction temperature, oxygen concentration, NH3-to-NO ratio, space velocity, heating area, catalyst arrangement, and vanadium coating on the removal of nitric oxide. The investigation showed that the change of the parameters significantly affected the removals of NO and NH3 species, the residual NH3 concentration (or NH3 slip), the temperature of the maximum NO reduction, and the temperature of complete NH3 conversion. The reaction temperature was increased from the ambient temperature (25°C) to 450 °C. For both catalysts, high NO and NH3 removals were obtained in the presence of a small amount of oxygen, but no significant influence was observed from 0.1 to 3.0% O2. An increase in NH3-to-NO ratio increased NO reduction but decreased NH3 conversions. For V2O5-WO3/TiO2, the decrease of space velocity increased NO and NH3 removals and broadened the active temperature window (based on NO > 88% and NH3 > 87%) about 50°C. An increase in heating area decreased the reaction temperature of the maximum NO reduction from 350 to 300°C, and caused the active reaction temperature window (between 250 and 400°C) to shift toward 50°C lower reaction temperatures (between 200 and 350°C). The change of catalyst arrangements resulted slight improvement for NO and NH3 removals, therefore, the change might contribute to more gas removals. The catalyst with extra vanadium coating showed higher NO reductions and NH3 conversions than the catalyst without the extra vanadium coating.

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In order to fulfil the requirements in the EURO VI standard, regulating emissions from heavy duty vehicles, the exhaust aftertreatment system needs to maintain its efficiency for at least seven years or 700 000 km. In diesel applications the diesel oxidation catalyst (DOC) is located closest to the engine and is thus the most vulnerable to poisoning contaminants, such as phosphorus originating from fuel and oil additives, which deactivates the catalyst. An idea to reduce the impact from phosphorus impurities (recently patented by Scania CV) is to place a low-cost sacrificial substrate, consisting of one or more pillared clay mineral (PILC) with high affinity for phosphorus, upstream the aftertreatment system in order to protect and thus increase the lifetime of the catalytic components which contain platinum group metals. In this work one commercially available and four custom made PILCs, comprising of two conventional type PILCs and two of the type porous clay heterostructures (PCH), were evaluated. The PILCs were exposed to a phosphorus-containing gaseous mixture using a lab-scale experimental setup in order to determine their phosphorus sorption potential. The PILC materials exhibit potential to function as sacrificial substrates for phosphorus in the intended application. It was indicated to be a correlation between increasing iron content (wt%) and increasing phosphorus sorption capability. The most promising material was the custom made Al,Fe-pillared saponite, which was up to twice as effective in trapping phosphorus as the DOC. The commercial sample, the Al-pillared montmorillonite, was only about as efficient as the DOC.

Neisseria meningitidis is an obligate human pathogen causing over 1000 cases of meningococcal disease within the U.K., 10 % of which result in long-term disability or fatality. 10-70 % of the population carry N. meningitidis in their nasopharynx, the natural reservoir of this bacterium, as a commensal. The host-pathogen interactions of this species are complex and a greater understanding of the molecular mechanisms involved in pathogenesis and immune evasion is required. Three aspects of N. meningitidis pathogenesis were explored in this study. One mechanism of immune evasion which promotes serum resistance of N. meningitidis is recuitment of complement factor H through domains 6 and 7 (fH₆₇) by factor H binding protein (fHbp). In this study, mouse fH₆₇ was recombinantly expressed and purified. fHbp did not bind mouse fH₆₇ at physiologically relevant protein concentrations. The structure of mouse fH₆₇ was solved, showing differences in domain orientation and surface chemistry compared to the human version of this protein, potentially accounting for the host specificity of this interaction. Type IV pili (T4P) are crucial adhesins of N. meningitidis, the fibre of which is composed of thousands of copies of PilE. A method was developed to recombinantly produce large quantities of this protein from a variety of meningococcal strains and the structure was solved of one PilE protein. Subsequent analysis was performed with the PilE proteins investigating their interaction with the putative pilus receptor CD46 and human epithelia as well as their immunogenicity. A method was also established to produce PilC, the proposed tip-assocoated adhesin of T4P. ZapE has recently been identified as an important protein in pathogen colonisation, functioning as an ATPase linked to Z-ring formation in bacterial cell fission. Both N. meningitidis and E. coli ZapE were recombinantly produced. The domain boundaries were mapped and ATPase activity was confirmed. No interaction was seen with FtsZ but DNA binding and modulation was observed by shift assays, the exact function of which remains to be elucidated in future studies.