Co2 Removal Using Imidazolium-Based Ionic Liquid -Aspen Plus Modelling Study

Abstract

Novel technologies that decrease the level of CO2 in our atmosphere are crucial for minimizing the potential risks associated with climate change, and immediate advancements are needed for such technologies to operate at global level. Ionic liquids are getting prominence as environmentally sustainable solvents, especially as alternatives to traditional media in chemical processes for CO2 capture. This innovative approach of capturing CO2 is extremely effective and affordable. Ionic Liquids (IL) are genuinely customizable solvents since it is possible to adjust the chemical structure of IL to vary nearly all of its physical and chemical characteristics. Despite the fact that ionic liquids have yet to be used on a wide scale and that the industry is still trailing behind mid-term expectations, their advantages suggest that they might one day become a commercial success. This simulation study investigates the potential of using an ionic liquid as a solvent for carbon sequestration to reduce CO2 emissions and purify industrial waste streams. Specifically, the absorbent EMIMNTF2 (1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide) is studied for its ability to capture CO2 and high energy savings. The study uses the ASPEN PLUS V11 software with the COSMOSAC property model to examine the impact of changing waste stream compositions on process performance, optimize the flow rate of the ionic liquid, and assess the effects of temperature, and vapor/liquid flow ratios on absorber stages. The study also performs an economic analysis and heat integration to demonstrate the efficacy and suitability of the Aspen Plus model in simulating IL absorption with a high percentage of CO2 capture. Results show that [EMIM][NTF2] can remove up to 99.4% of CO2 from waste industrial effluents using three distinct compositions. Additionally, a flow rate of 20,000 kg/h for the ionic liquid is optimized for the highest purity values of CO2 and CH4, and the total annualized cost for the process is 2.1 million dollars with operating expenses of 1.8 million dollars for a 20-year of plant life with a plant capacity of 4000 kg/h (0.035 Mt/year). This study proposes a conceptual framework for developing novel ionic liquids for CO2 capture and demonstrates that sustainable [EMIM][Tf2N]-based absorption technique for CO2 capture has the potential to be an industrial technology.