| Facing worsening environmental problems and increasingly stringent emission regulation, three-way catalytic converter technology has become an important part of automotive exhaust treatment. Three-way catalytic convener for long-term use the ageing of catalytic efficiency, resulting in automobile emissions increase, on aging characteristics of three-way catalytic convener to ensure that the work of the three-way catalytic convener long-term stability, it is of great significance. With the rapid aging test method for fast and accurate assessment of three way catalyst aging properties, it can save a lot of costs, so the rapid aging of three-way catalytic convener by more and more attention.Article describes the development of three-way catalytic converter at home and abroad, domestic production of vehicle emission control enterprise's development situation, three-way catalytic conversion of aging research, based on the aging evaluation methods for three-way catalytic converter at home and abroad, establish aging of article to the programme. Also describes the structure and composition of three-way catalytic converter, chemical composition of catalyst in catalytic converters, catalytic mechanism, nature of the catalyst, the catalyst works, characteristics of three-way catalytic converters, including the air-fuel ratio characteristics, ignition characteristics and so on. Aging mechanism of catalytic converters, aging form 4 classes on three-way catalytic converters made a detailed presentation.Article aging program is air cycle controls of HJ/T331-2006, catalytic converters on the vehicle accelerated aging test equipment for the overall design and build the aging test bench, and electronic control air systems, data acquisition system, the detailed design of the cooling system, and subsystem solutions including design, test equipment selection, hardwareconnections, software debugging.According to the test problems in the process of debugging, optimize test equipment. Organize and complete 100 hours aging test, followed by the aging of catalytic converters after the qualification test.Analysis of experimental data showed that three-way catalytic converter after 100h aging CO,HC,NOx combustion temperature rise respectively 41℃,41℃,29℃, to the disadvantage of catalytic combustion; After aging in an ideal air-fuel ratio (14.7) operating conditions, HC,CO,NOx catalytic efficiency of all three gas to 80% and the remainingconditions of low catalytic efficiency, efficient window air-fuel ratio characteristics of virtually non-existent, because the aging HC the conversion efficiency was significantly reduced catalytic performancetended to deteriorate.The test on the ageing of the catalysts for a normal aging test, on service life of catalyst performance, does a scientific assessment of the performance.
|
PDF Full Text Request