Recently, after review and recommendation by the Degree Evaluation Subcommittee of Tianjin University, the article " Design, synthesis and performance evaluation of novel small pore zeolite for DeNOx in diesel exhaust" completed by Han Jinfeng, a doctoral student under the guidance of professor Liu Qingling, was awarded the excellent dissertation.

      Diesel vehicles are widely used due to their strong power and good economy. However, NOx emissions in their exhaust gas have become not be ignored. At present, ammonia selective catalytic reduction (NH3-SCR) technology is considered to be one of the most effective technologies for removing NOx from diesel exhaust, and the key is the catalysts. Among the catalysts of DeNOx, copper-based small pore zeolite catalysts have become the current hotspot because of their excellent NH3-SCR activity, high N2 selectivity and good hydrothermal stability. The bottleneck of the catalyst is that the higher silicon-aluminum ratio (Si/Al > 8) zeolite catalysts have good hydrothermal stability, but the synthesis cost is high and the crystallization time is long. Low silicon-aluminum radio (Si/Al < 6.5) zeolite catalysts have good low temperature activity and wide temperature activity due to the rich in acidity and ion exchange site, however, the hydrothermal stability still need to be improved. Based on the above difficulties, for the high silicon-aluminum ratio zeolite catalyst, high Si/Al radio SSZ-13 zeolite was rapidly synthesized from industrial solid waste coal gangue. On the basis of ensuring catalyst performance, the cost of synthesized zeolite was reduced and the crystallization time was shorted to half. Otherwise，XRD, transmission and other characterization methods were used to anslyse the rapid synthesis mechanism. For the low silicon-aluminum ratio zeolite catalyst, novel Al-rich twin-crystal zeolites, such as OFF-CHA and OFF-ERI, with excellent NH3-SCR activity and hydrothermal stability were synthesized. And the reasons for the excellent performance of the catalyst were analyzed by means of H2-TPR, NH3-TPD, FTIR, NMR and other characterization methods. This study provides a theoretical basis and reference for the research and development of DeNOx catalysts with low cost and high performance in diesel exhaust.