| The most popular and classical NSR catalyst Pt/Ba/Al2O3exhibits poor sulfurresistance, and the conventional co-precipitation method results in limited surface areaand component dispersion. So, exploring novel NSR catalysts with improvedpreparing method is of great significance. In this work, the Pt/K/TiO2-Al2O3catalystwas successfully prepared with the support synthesized by citric acidcomplexation-organic template decomposition method. The NOx storage/reductionperformance and sulfur-resisting ability of the catalysts were carefully evaluated.Meanwhile, the effect of La2O3additive was probed, too.Firstly, mesoporous TiO2-Al2O3binary oxide supports with high surface areawere successfully prepared by using the mixture of nonionic p-octyl polyethyleneglycol phenyl ether （OP） and the cationic cetyltrimethyl-ammonium bromide （CTAB）as co-templates. The NOx storage/reduction performance and the sulfur-resistingability of the corresponding Pt/K/TiO2-Al2O3catalyst are much better than thoseobtained by conventional co-precipitation method or by using CTAB as singletemplate.Secondly, to improve the thermal stability of the obtained mesoporous catalysts,the support TiO2-Al2O3was further modified by La2O3. The addition of La2O3couldgreatly improve the component dispersion and the thermal stability of the catalysts,enhancing both the storage/reduction performance and the sulfur-resisting ability ofthe catalysts. Meanwhile, the sample Pt/K/TAL-CTAB-OP is still the best one amongthe catalysts with supports prepared by different methods.Thirdly, the anionic surfactant sodium dodecyl sulfate （SDS） was introduced toreplace the nonionic CTAB, and the mesoporous TiO2-Al2O3supports were preparedby using the mixture of OP and SDS as co-templates. The corresponding catalystPt/K/TiO2-Al2O3possesses a much better performance in both NOx storage/reductionand sulfur resistance than the differently prepared samples as referred above,possessing a great potential for real application. |
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