Optimized TWC for emission control on a heavy duty stoichiometric CNG engine
2022-01-0706
03/29/2022
- Event
- Content
- Compressed natural gas (CNG) engines have attracted increasing attention in the heavy duty (HD) vehicle market as an alternative to conventional diesel fuel often due to the abundance and low price of CNG. However, it is challenging to meet the increasingly stringent China VI legislation, particularly for hydrocarbons (mainly CH4), carbon monoxide (CO), nitrogen oxides (NOx) and ammonia (NH3). In this work, approaches were explored in which a gasoline three-way catalyst (TWC) was modified through the optimization of materials and design. The optimized TWC was evaluated in a laboratory reactor and with a HD stoichiometric CNG engine. Lab reactor results showed improve CH4 light off performance. Ammonia (NH3) is a by-product during the operation of three-way catalysts (TWC) on a stoichiometric CNG engine. Catalytic modifications are discussed which were demonstrated to reduce NH3 emissions due to the relatively low NH3 limit for China VI legislation. Data are reported demonstrating the optimized TWC passed 1200hrs engine durability testing.
- Citation
- Qiao, D., Wang PhD, J., Chuma, H., Hu, H. et al., "Optimized TWC for emission control on a heavy duty stoichiometric CNG engine," SAE Technical Paper 2022-01-0706, 2022, .