MnO_2/NaY复合材料的制备及其对SO_2脱除性能

Preparation of MnO_2/NaY composite and its performance in removing SO_2

以NaY分子筛为载体,MnO_2为活性组分,采用沉淀法制备MnO_2/NaY复合脱硫材料;通过X射线衍射(XRD)、扫描电子显微镜(SEM)、氮气吸附脱附法(N2-吸附脱附)、X射线光电子能谱(XPS)、热重分析(TG)等手段进行材料的物理化学结构表征;使用容量法装置测试复合材料的脱硫性能;考察MnO_2不同负载量及不同反应温度对MnO_2/NaY复合材料脱硫性能的影响。结果表明:MnO_2/NaY复合材料的孔容越大,其脱硫性能越好;多孔珊瑚状MnO_2脱硫性能优于棒状MnO_2;随着MnO_2负载量及反应温度的增加,MnO_2/NaY的脱硫性能先增加后降低,MnO_2/NaY-41%在400℃时的脱硫性能最好,第1h脱硫量达到114.56mgSO_2/g材料;500℃时复合材料脱硫性能下降,是由于脱硫反应过程中MnO_2分解生成Mn_3O_4;MnO_2/NaY比纯MnO_2拥有更好的脱硫性能,反应温度为300℃和400℃时,MnO_2/NaY-41%较纯MnO_2的第1h脱硫量分别提高28.3%和56.1%。MnO_2/NaY-41%复合材料在中低温下的高效脱硫性能有望应用于船舶尾气的深度脱硫。

MnO2/NaY composite for desulfurization was prepared by precipitation method with NaY molecular sieve as the carrier and MnO2 as the active component. The structure of the MnO2/NaY composite was characterized by X-ray diffraction(XRD), scanning electron microscope(SEM), nitrogen adsorption desorption(N2-adsorption desorption), X-ray photoelectron spectroscopy(XPS) and thermogravimetry(TG). The capacity method was used to test the desulfurization performance of the composite material and the influence of different loading capacity of MnO2 and different reaction temperature were studied. The results showed that the larger the pore volume of MnO2/NaY composite, the better the desulfurization performance. Porous coral MnO2 has better desulphurization performance than rod-like MnO2. The desulfurization performance of MnO2/NaY increased first and then decreased with the increase of MnO2 loading amount and reaction temperature. MnO2/NaY-41% showed the best desulfurization performance at 400℃, and the desulfurization capacity reached 114.56 mgSO2/gMaterialsin 1 h.The decline in desulfurization performance at 500℃ is due to the decomposition of MnO2 into Mn3O4 during the desulfurization process. The MnO2/NaY showed better desulfurization performance than pure MnO2. When the reaction temperature reached 300℃ and 400℃ respectively, the desulfurization performance of MnO2/NaY-41% was higher than that of pure MnO2 by 28.3% and 56.1% in 1 h. The composite is expected to be applied in the desulfurization of marine exhaust gas.