Experimental evaluation of zeolite 13X and activated carbon as adsorbents in a carbon capture system for ICE exhaust gases

• First evaluation of sorbents for CO 2 capture in an ICE under partial load. • Zeolite 13X captures 13% more CO 2 and extends capture duration by 33 % vs AC. • CO 2 loading capacity of the evaluated sorbents differs by 90% from literature values. • Engine power penalty from CCS system decreases at high rpm due to increased exhaust gas heat. • CO 2 capture energy consumption is around 3900 kJ/kg with Zeolite 13X. Given the urgent need to mitigate climate change, reducing CO 2 emissions produced by internal combustion engines (ICEs) remains a critical challenge in the transport sector. Onboard carbon capture (CC) systems have emerged as a promising alternative, attracting growing research interest in recent years. However, most studies are limited to simulations, with experimental evidence still scarce. Based on the above, this study experimentally evaluates zeolite 13X (Z13) and activated carbon (AC) as sorbents for CO 2 capture in ICEs. For this purpose, an adsorption-based CC system was integrated into the exhaust duct of an ICE operating under partial loads and at two engine speeds. The experimental data were subsequently employed to develop a simulation case study aimed at performing an energy assessment of a carbon capture and storage (CCS) system based on temperature swing adsorption. The results show that the sorbent Z13 demonstrated a 13 % higher CO 2 adsorption capacity and a 33 % longer capture duration than AC, though average carbon capture rates (CCR) remained moderate (25 % for Z13 and 16 % for AC). The case study results showed that the carbon capture and storage (CCS) system with Z13 achieves a maximum CCR of up to 37 %, an energy penalty of approximately 30 % of the engine’s power output and an average energy consumption for CO 2 capture of 3900 kJ/kgCO 2 . Conversely, the CCS system with AC did not provide suitable CCR or energy performance under any scenario. The case study also demonstrates that the CCS system has a better performance when the engine is operated at medium or higher loads.