Effect of biofuel- and lube oil-originated sulfur and phosphorus on the performance of Cu-SSZ-13 and V2O5-WO3/TiO2 SCR catalysts

Publication date: Available online 21 February 2020Source: Catalysis TodayAuthor(s): Sandra Dahlin, Johanna Englund, Henrik Malm, Matthias Feigel, Björn Westerberg, Francesco Regali, Magnus Skoglundh, Lars J. PetterssonAbstractTwo different SCR catalysts, V2O5-WO3/TiO2 and Cu-SSZ-13, were exposed to biodiesel exhausts generated by a diesel burner. The effect of phosphorus and sulfur on the SCR performance of these catalysts was investigated by doping the fuel with P-, S-, or P + S-containing compounds. Elemental analyses showed that both catalysts captured phosphorus while only Cu-SSZ-13 captured sulfur. High molar P/V ratios, up to almost 3, were observed for V2O5-WO3/TiO2, while the highest P/Cu ratios observed were slightly above 1 for the Cu-SSZ-13 catalyst. Although the V2O5-WO3/TiO2 catalyst captured more P than did the Cu-SSZ-13 catalyst, a higher degree of deactivation was observed for the latter, especially at low temperatures. For both catalysts, phosphorus exposure resulted in suppression of the SCR performance over the entire temperature range. Sulfur exposure, on the other hand, resulted in deactivation of the Cu-SSZ-13 catalyst mainly at temperatures below 300-350 °C. The use of an oxidation catalyst upstream of the SCR catalyst during the exhaust-exposure could protect the SCR catalyst from phosphorus poisoning. The results in this work will improve the understanding of chemical deactivation of SCR catalysts and aid in developing durable aftertreatment ...

Source: Catalysis Today - February 21, 2020 Category: Chemistry Source Type: research