La2O3掺杂对CDPF老化性能的影响

Effect of La2O3 doping on the aging performance of catalyzed DPF

摘要:

本文基于XRD、XPS、H2-TPR等表征方法以及活性评价方法,研究了不同浓度La2O3掺杂CDPF样品水热老化状态下的理化特性与催化活性,结果表明：随着La2O3掺杂浓度增加,CDPF老化样品衍射特征峰位向大角度偏移程度以及结晶度均呈先降低后增加的趋势。La2O3掺杂能够较好地抑制样品在高温水热老化过程中的烧结和畸变,并且可以有效抑制活性位数量的减少,使CDPF表面Pt原子浓度基本保持不变,对CO、C3H8和NO催化性能的劣化率降低,并且随掺杂浓度的增大,CDPF抗老化性能有增强的趋势。

Abstract:

Based on XRD, XPS, H2-TPR and other characterization methods and activity evaluation methods, the physical and chemical properties and catalytic activity of CDPF samples doped with different concentrations of La2O3 under hydrothermal aging condition were studied. The results show that with the increase of La2O3 doping concentration, the diffraction characteristic peak shifts a large angle and crystallinity of CDPF aging samples show a trend of decreasing then increasing. La2O3 doping can better inhibit the sintering and distortion of samples during hydrothermal processing and can effectively inhibit the reduction of active quantity, so that the concentration of Pt atoms on the surface of CDPF remains basically unchanged, and the degradation rate of CO, C3H8 and NO catalytic performance decreases. With the increase of doping concentration, the CDPF tends to reverse the trend of ageing.