Performance evaluation of CO2 capture on using potential adsorbents in a CI engine exhaust–An experimental investigation

Anthropogenic activites release greenhouse gas emissions into our atmosphere, especially carbon dioxide (CO₂). This abundant accumulation of CO₂ generates numerous problems like global warming and climate change. However, research has been conducted to capture CO₂ from significant single-point emitters like compression ignition (CI) engines, backup generators, and distributed power production plants. Moreover, research has also been done on post-combustion adsorption chamber to capture CO₂ emissions from small stationary engines. Biomass-based activated carbon as an adsorbent for capturing CO₂ from engine exhaust has recently been investigated. Three biomass-based adsorbents, (a) coconut shell adsorbent, (b) rice husk adsorbent and (c) eucalyptus wood adsorbent, are used in the capture unit to trap CO₂ from the CI engine exhaust. This study uses a single-cylinder, four-stroke, air-cooled, naturally-aspirated, direct-injection (DI) CI engine running at a constant speed of 1,500 rpm and producing power of 4.4 kW. The adsorption performance of adsorbent samples is investigated by coupling the adsorption chamber to the exhaust system of a test engine operated on diesel (D100) at various loads. Temperature swing adsorption (TSA) is used to regenerate the original adsorbent. The adsorbents’ adsorption capacities are evaluated by performing multiple adsorption–desorption test cycles using the same adsorbents. During TSA, CO₂ released from the capture unit is further captured and stored in a gas bag. The captured gas sample is characterized through gas chromatography-mass spectroscopy (GC-MS) characterization to examine and ensure the gas adsorption efficacy of adsorbent samples. The outcomes of this research study are discussed and presented in detail. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd.