稻壳基活性炭催化剂的低温NH3-SCR抗硫性能

以稻壳基活性炭（DAC）为载体，利用等体积浸渍法制备了DAC负载Mn、Ce氧化物的Mn-Ce/DAC脱硝催化剂，并用于氨法SCR反应.采用N₂吸附、X射线衍射（XRD）、X射线光电子能谱（XPS）和程序升温吸附脱附（TPR/TPD）等手段对催化剂的物理化学性能进行了表征.结果发现与商业木屑基活性炭负载Mn、Ce氧化物催化剂（Mn-Ce/MAC）相比，Mn-Ce/DAC具有更高的Ce³⁺/Ce⁴⁺比率、表面化学吸附氧含量以及表面Brønsted酸性位点，这与其优良的低温SCR活性及抗硫抗水性能直接相关.原位红外光谱结果显示在含硫气氛中Mn-Ce/DAC表面的硫酸盐含量明显低于Mn-Ce/MAC，表明前者具有优良抗硫性能.

Sulfur resistance of rice husk based activated carbon catalyst for the low-temperature selective catalytic reduction of NO by NH3

A rice husk-derived activated carbon supported Mn-Ce catalyst (Mn-Ce/DAC) was prepared by an impregnation method and tested for the selective catalytic reduction of NO_x with NH₃. Such catalysts were characterized by N₂ adsorption, X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPR/TPD). The characterization results indicated that Mn-Ce/DAC catalyst exhibited the higher Ce³⁺/Ce⁴⁺ ratio, chemisorbed oxygen and Brønsted acid sites than commercial sawdust-derived activated carbon supported Mn-Ce catalyst (Mn-Ce/MAC). All of these factors played significant roles in the high SCR activity and SO₂ resistance. In situ DRIFTS results demonstrated that sulfate formation was suppressed on the surface of the DAC support, which might be the most significant reason that Mn-Ce/DAC maintained a high SCR activity in the presence of SO₂.