Response Surface Optimization of Nonaqueous Hexanol‐Based Trisolvent Amine Blends for Energy‐Efficient CO₂ Desorption

Abstract

The CO2 absorption–desorption performances of nonaqueous trisolvent blended amines, monoethanolamine (MEA), 2‐amino‐2‐methyl‐1‐propanol (AMP), methyl diethanol amine (MDEA), 1‐dimethyl amino‐2‐propanol (1DMA2P), diethyl ethanol amine (DEEA), and piperazine (PZ), are investigated in terms of desorption parameters. Two trisolvent amine combinations, primary amine (MEA)/sterically hindered amine (AMP) and tertiary amine (MDEA/1DMA2P/DEEA)‐polyamine (PZ), are prepared at 5 m total amine concentrations with different molarities. Response surface methodology based on a central composite design is used to obtain the optimal condition. This study aims to determine the molarity ratios of solvent systems and investigate their effects on objective functions: heat duty, desorption rate, and desorption factor. Surface analysis suggests optimum conditions as 3 m MEA–1.375 m MDEA–0.625 m PZ for the lowest energy consumption. The experimental results of the proposed system are compared with the 5 m MEA solution. The extensive energy penalty of the CO2 desorption of amine absorbents is reduced with the newly developed solution.