Storage of Nitrous Oxide (NOx) in Diesel Engine Exhaust Gas using Alumina-Based Catalysts: Preparation, Characterization, and Testing

A. Alsobaai, Chemical Engineering Department, Faculty of Engineering and Petroleum, Hadhramout University, Mukalla, Yemen.

Abstract

This work investigated the nitrous oxide (NOx) storage process using alumina-based catalysts (K2 O/Al2 O3 , CaO/Al2 O3, and BaO/Al2 O3 ). The feed was a synthetic exhaust gas containing 1,000 ppm of nitrogen monoxide (NO), 1,000 ppm i-C4 H10 , and an 8% O2 and N2 balance. The catalyst was carried out at temperatures between 250–450°C and a contact time of 20 minutes. It was found that NOx was effectively adsorbed in the presence of oxygen. The NOx storage capacity of K2 O/Al2 O3 was higher than that of BaO/Al2 O3. The NOx storage capacity for K2 O/Al2 O3 decreased with increasing temperature and achieved a maximum at 250°C. Potassium loading higher than 15% in the catalyst negatively affected the morphological properties. The combination of Ba and K loading in the catalyst led to an improvement in the catalytic activity compared to its single metal catalysts. As a conclusion, mixed metal oxide was a potential catalyst for de-NOx process in meeting the stringent diesel engine exhaust emissions regulations. The catalysts were characterized by a number of techniques and measurements, such as X-ray diffraction (XRD), electron affinity (EA), a scanning electron microscope (SEM), Brunner-Emmett-Teller (BET) to measure surface area, and pore volume and pore size distribution assessments.

Recommended Citation

Alsobaai, A. (2017) "Storage of Nitrous Oxide (NOx) in Diesel Engine Exhaust Gas using Alumina-Based Catalysts: Preparation, Characterization, and Testing," The Journal of Engineering Research: Vol. 14: Iss. 1, Article 3.
DOI: https://doi.org/10.24200/tjer.vol14iss1pp64-73