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Nitric oxide and sulfur dioxide from the exhaust gases of marine diesel engines are harmful for the environment and human health. Environmentally friendly sodium persulfate, which satisfies the requirements of ships and navigation, was used as the main absorbent for the simultaneous removal of SO2 and NO in a self-designed bubble column reactor with an industrial gas distributor in this work. The focus of this work was the absorption of the insoluble NO. The influences of various parameters including the reaction temperature, Na2S2O8 concentration, NO concentration, pH value of the solution, and presence of coexisting gases on NO absorption were comprehensively and systematically studied according to the different working conditions of marine diesel engines. Furthermore, experiments for simultaneously removing SO2 and NO were conducted. Different from the previous studies, the new experimental results showed that the increase of NO concentration and the pH value of 12 were not conducive to the NO absorption; the highest removal efficiency of NO was at pH of 9; the existence of sulfur dioxide weakened the absorption of nitric oxide; the final products of the simultaneous absorption were sulfate and nitrate according to the product detection results. However, the SO2 and NO in simulated exhaust gases (900 ppm SO2, 1000 ppm NO, 15% O2 and 5% CO2) from marine diesel engines were completely absorbed under nonoptimal conditions (at 70 °C and in a 0.15 mol/L sodium persulfate solution), which indicated that sodium persulfate is promising for use in wet emission control technologies for marine diesel engines.