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The flue gases emitted from boilers such as waste incineration plants and thermal power plants often contain a certain amount of Pb. This Pb can cause the NH3-SCR catalyst to deactivate, thereby increasing NOx emissions. To address this issue, phosphorylated MCM-22 was used as the support for CeO2-ZrO2 nanospheres to synthesize CZMP catalysts with strong Pb poisoning resistance. These catalysts were able to purify more than 80% of NOx at a temperature of 300 °C after Pb poisoning. X-ray diffraction, powder FT-IR, and TEM analyses revealed that the structure and composition of the catalyst is stable and unchanged before and after Pb poisoning. NH3-TPD result showed that phosphoric acid modification could change the acidity of the catalyst and H2-TPR indicated the increase of low temperature redox sites, enhancing its anti-poisoning ability at low temperatures. In-situ DRIFT studies indicated that phosphoric acid modification caused rapid decomposition of nitrate intermediates on the catalysts, with the reaction dominated by an E-R mechanism
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