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The deactivation of a silver-based hydrocarbon selective catalytic reduction catalyst by SOx and the subsequent regeneration under various operating conditions has been investigated. Using a sulfur trap based on a silica-supported catalyst it was found that, for a Ag/SiO2 + Ag/Al2O3 combination, the negative effect of SO2 on the n-octane-SCR reaction can be eliminated under normal operating conditions. The trap can be regenerated by hydrogen at low temperatures or at higher temperatures using a hydrocarbon reductant.

M.Tech. (Chemistry) This work focused on the in-situ decoration of polyethersulfone (PES) nanofiber mats with silver nanoparticles (AgNPs) using an electrospinning technique. The biocidal and organic properties of the Ag decorated nanofibers were evaluated. Electrospinning of Ag decorated nanofibers was also carried out on a mixed matrix membrane support composed of nitrogen doped carbon nanotube (N-CNTs) and PES to fabricate a unique bi-faceted membrane. PES was dissolved in a solution containing silver nitrate (AgNO3) and N,Ndimethylacetamide (DMAc). The polymer solution was dissolved at 80ºC for 3 h under reflux until a yellow homogeneous solution was obtained which indicated the in-situ formation of AgNPs. The polymer solution was cooled and stored to remove air-bubbles. An ultraviolet - visible (UV – Vis) spectrometer was used to confirm the presence of AgNPs, while a Malvern nanosizer was used to estimate the size distribution of the AgNPs in the PES polymer matrix. The solution was electrospun on an aluminium (foil) collecting plate. Biocidal properties of the material were evaluated using Gram-positive (G+) Staphylococcus aureus (S. aureus) and ram-negative (G-) Escherichia coli (E. coli) by the zone inhibition method. The silver decorated polyethersulfone nanofibers showed good antibacterial activity against both G+ S. aureus and G- E. coli.