화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.44, No.54, 29057-29065, 2019
Advanced thermally stable, self-sustaining NiCo2O4 catalyst for CNG emissions in lean burn environment
Compressed Natural gas (CNG) has considerable potential as a "clean" fuel for motor vehicles. Though, CNG is cleaner fuel, vehicles running on it emit primary pollutants such as carbon monoxide (CO), nitrogen oxides (NOx) and hydrocarbons (HC) predominantly methane (CH4). US EPA greenhouse gas legislation and Euro VI have imposed strict emission regulations with special emphasis to control greenhouse gases (GHG), demanding vehicles to use advanced after-treatment technologies in order to control GHG emissions. NiCo2O4 catalyst prepared by nano-casted nitrate precursor followed by reactively calcination was used for the SCR of NO emission from Compressed Natural gas vehicles (CNGVs) using CO-CH4 as reductant. Catalyst is self-sustained as it is as redox catalyst which works efficiently in the presence of CO-CH4 reductant inherently present in the gas stream. The experimental results showed that NiCo2O4 catalyst was highly active reducing 96.5% NO at 400 degrees C. Being an active redox catalyst, NiCo2O4 also facilitates simultaneously oxidation of CO and CH4 to the extent of 95% within the same range of temperature. Therefore, NiCo2O4 catalyst can be suggested for the complete emission control of CNG fueled vehicles. It is very sturdy catalyst as despite a high CH4 oxidation temperature the catalyst showed a stable behavior over a 50 h run. Finally, the above mentioned catalyst can pave the way for the current CNG tail-pipe-technology challenges. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.