Simulation and 3E assessment of pre-combustion CO2 capture process using novel Ionic liquids for blue H2 production

Abstract

Incorporating pre-combustion CO2 capture with H2 production is expected to be a crucial technology that significantly contributes to CO2 emissions reduction from the current H2 production methods that rely on natural gas. This work evaluates the exergy, energy, and economic aspects of a CO2 capture process using new ionic liquid (IL) [NMIM][DCN] for H2 production, and compares it with the established IL [HMIM][DCN]. The package "PySCF" in Python was used for geometry optimization, and a COSMO-based/Aspen approach was employed for component definition in Aspen Plus. The pre-combustion CO2 capture was simulated using Aspen Plus V12. Through the simulation, it was evident that IL [NMIM][DCN] exhibited promising results with a CO2 capacity of 92.84% and 99.7% H2 recovery, in contrast to [HMIM][DCN] (CO2 capacity: 80% and H2 recovery: 94.6%). Additionally, [NMIM][DCN] demonstrated lower energy consumption, utility cost and CAPEX compared to [HMIM][DCN] due to its low energy requirement for CO2 separation. However, it is noteworthy that exergy and OPEX values were significantly high for [HMIM][DCN], and this suggests further analysis to optimize the [HMIM][DCN]-based process.