Cooperative Integration of SCR and CESAR-1: Mechanism and Performance

Limiting carbon dioxide (CO₂) emissions from large point sources such as thermoelectric plants is a central challenge for mitigating global warming. Among post-combustion capture methods, amine-based absorption using CESAR-1, a blended (AMP)/(PZ) solvent, has been widely used due to its higher CO₂ loading capacity and lower regeneration energy. However, the presence of nitrogen oxides (NO, NO₂) in flue gas imposes a critical limitation: during solvent regeneration, nitrogen oxides promote degradation of CESAR-1, leading to the formation of carcinogenic nitrosamines and nitramines, which are known to be toxic. This paper reviews the distinct characteristics of AMP and PZ, the two components of CESAR-1, as well as the reaction mechanism underlying CO₂ capture in CESAR-1 system. Also, it focuses on the solvent degradation pathway that occurs in the presence of nitrogen oxides, and the mechanism of selective catalytic reduction (SCR). Building on these concepts, we propose an integrated SCR-CESAR-1 system that combines SCR with CESAR-1, an amine-based solvent, to reduce CO₂ emissions while minimizing the risk of undesired byproduct formation. Furthermore, by optimizing the catalyst used in the SCR system, the suggested system aimed to minimize energy consumption across the system.