Development of an Energy-efficient CO2 Capture Process Using Thermomorphic Biphasic Solvents

A novel CO2 capture system using thermomorphic biphasic solvent (TBS) has been studied in this work. It exhibits a thermal-induced liquid-liquid phase separation (LLPS) behaviour, which intensifies CO2 desorption at temperature of 80 °C and therefore enables using low value heat ca. 90 °C to reduce the process operating cost. To regulate the phase change behaviour, blended amine solvents were formulated for attaining a homogeneous solution in absorption and biphasic system in regeneration. Thermal and oxidative degradations were also surveyed for the selected amines and the degradation products were analysed by gas chromatography - mass spectrometry (GC-MS). A bench-scale unit with a glass column of 40 mm inner diameter and random packings of 1 m height was employed for measuring the pressure drop and liquid hold-up as well as other physicochemical properties to assess the technical feasibility of such novel system.