Efficient selective combustion of n-butylamine on hierarchical Cu-Mn/SAPO-34 catalysts: The effect of mesoporosity and acidity

The efficient catalytic oxidation of nitrogen-containing volatile organic compounds remains a big challenge due to unmanaged production of harmful byproducts. Herein, a series of Cu-Mn modified hierarchical SAPO-34 zeolite catalysts with different pore structures were synthesized for n-butylamine oxidation. The physicochemical properties and catalytic performance of catalysts were investigated and analyzed in detail. Among them, CuMn/S-1 shows the highest activity (T-90 = 279 degrees C, GHSV = 12,000 h(-1)), which is attributed to its higher porosity, higher surface acidity and superior reducibility. Meanwhile, it is found that the hierarchical structure and mesopore play an important role in improvement of N-2 selectivity. Meanwhile, CuMn/S-1 also exhibits high stability and water resistance. The catalytic mechanism of n-butylamine on CuMn/SAPO-34 was investigated by in situ DRIFTS, showing that propanol, methanol and acetate are the main intermediates.