Testing Catalysts for their Activity and Sulfur Tolerance under Simulated Smouldering Environment

Catalysts are frequently used to treat exhausts from automotive vehicles and chemical industries but their ability to treat emissions generated from the incineration of human waste is still unexplored. Three catalysts were examined in this thesis: 0.5% Pt/Al2O3 by Alfa Aesar, 0.5% Pt/Al2O3 by Hulteberg Group and 2%Pt-La2O3/25% ZrO2 -75% SiO2 by Riogen Inc. The results show that the three catalysts survived 4h of exposure to simulated smouldering effluent gas compositions. Propane and carbon monoxide oxidations after 12 h of accelerated poisoning conditions showed an increase and decrease in catalytic activity, respectively. Upon regeneration, the Riogen zirconia supported catalyst showed nearly complete reversal of decreases in sulfur-poisoning induced CO activity, while only partial reversal was seen for the two alumina supported catalysts. Lastly, adsorption and desorption studies showed that much more sulfur dioxide was desorbed from the zirconia-based catalyst than alumina-based catalysts - consistent with activity reversal observations.M.A.S