老化温度对汽车临界催化剂性能的影响初探

临界催化剂的制备是汽车车载诊断(OBD)系统标定认证的难点。高温快速水热老化方式是国五工况下常见的OBD催化剂制备方式之一，但该方式制备的老化温度与催化剂整车性能之间关系尚不明确。将同批催化剂在不同温度老化，采用整车排放、台架储氧能力(OSC)和比表面积(BET)共3项指标的测试，研究了各指标与老化温度的关系。结果表明，在拐点温度之前各项性能变化较平缓，其后随温度升高劣化幅度急剧加大，3项指标的拐点温度稍有差异。通过催化剂OSC或BET的测定，预估拐点温度，可以快速定位临界催化剂样件烧制的温度范围，简化制备流程。

Effect of Aging Temperature on the Performance of Automotive Critical Catalysts

The critical catalysts is vital for the calibration and certification of automobile OBD(on board diagnostic). High-temperature hydrothermal aging is one of common preparation methods for critical catalysts by China 5 emission regulation, however, the relationship between the aging temperature and the performance of the critical catalyst is not clear. In this paper, the same sample batch of catalysts were first aged at various temperatures, then tested their vehicle emissions, catalyst storage capacity(OSC) and specific surface area(BET), and investigated their correlations between individual indicator with ageing temperature. The results showed that the vehicle emission, OSC and BET performance slightly changed before reaching an inflection temperature, and that their performances sharply decreased with temperature. The inflection temperatures of vehicle emission, OSC and BET were slightly different. The inflection temperatures of OSC and BET are beneficial to narrow the annealing temperature range of critical catalysts, reduce the sample preparation number, and simplify the preparation process.