Abstract
Phase change absorbents are deemed a promising alternative for CO(2) capture due to their excellent CO(2) absorption performance, good stability, and low renewable energy consumption. To address the issues of insufficient loading capacity, low regeneration efficiency, and high energy consumption during regeneration in current chemical absorbents, a novel phase change absorbent was developed. As an amino acid ionic liquid phase change absorbent with tetraethylenepentamine as the cation, imidazole as the anion, and n-propanol as the phase separation agent, this absorbent offers a potential solution. The highest absorption capacity of the [TEPAH][Im]/NPA/H(2)O system at the optimal n-propanol-H(2)O ratio (1:1) reaches 1.34 mol·mol(-1), and the viscosity of the CO(2)-rich phase amounts to a mere 3.58 mPa·s. Additionally, the desorption efficiency reached 91.1% at 363.15 K, while the loading capacity in the fifth cycle remained over 1.16 mol·mol(-1). As n-propanol is present in the [TEPAH][Im]/NPA/H(2)O system, the rich phase makes up roughly 30% of the total volume. The energy consumption for regeneration of the [TEPAH][Im]/NPA/H(2)O phase change absorption system is 2.20 GJ·t(-1) CO(2). Under identical regeneration conditions, the system can reduce the regeneration energy consumption by 41.6%.