Dimensionless numbers for solubility and mass transfer rate of CO2 absorption in MEA in presence of additives.

Mohammadpour, Abdolah; Mirzaei, Masoumeh; Azimi, Alireza

• Solubility and absorption rate of commercial and nanoparticle of TiO 2. • Absorption behavior comparison of active carbon, CNT, graphite and graphene oxide. • Effect of TiO 2 , TBAB, SDS and GO, on the kinetic and solubility of CO 2 in MEA. • Introduce new dimensionless numbers (E S , E R and E T). • Evaluate optimum additive concentration of CO 2 absorption in MEA. This study aimed to compare the both solubility and mass transfer rate of CO 2 in monoethanolamine (MEA) in the presence of various additives, including Titanium dioxide (TiO 2) and Graphene oxide (GO) nanoparticles as well as two surfactants named Tetra -n- butylammonium bromide (TBAB) and Sodium dodecyl sulfate (SDS) using dimensionless numbers. Batch gas absorption experiments were performed at ambient temperature and various concentrations of additives from 0 to 0.1 wt.% at an initial pressure of 20 bar. By recording changes in the temperature and pressure of the gas in the loading tank, the number of CO 2 moles consumed was obtained in terms of time. The mass transfer coefficient and solubility were then calculated by kinetic and thermodynamic analyses. The dimensionless numbers, namely E S and E R , were calculated to analyze the behavior of the system. E S represents the solubility in the presence of an additive to that in the base solvent, whereas E S shows the mass transfer coefficient in the additive-containing solvent to that in the base solvent. The new, useful dimensionless number Et was defined to investigate the mass transfer rate and solubility simultaneously. For the additives used in this study, the highest E S , E R and E t were 1.31(0.0375 g of SDS), 1.25(0.075 g of TBAB) and 1.57(0.075 g of SDS), respectively. The results shows that surfactants have better effect on solubility and mass transfer rate of CO 2 in MEA.

DIMENSIONLESS numbers; MASS transfer; CARBON dioxide adsorption; SOLUBILITY; MASS transfer coefficients; GAS absorption & adsorption

Chemical Engineering Research & Design: Transactions of the Institution of Chemical Engineers Part A, 2019, Vol 151, p207

0263-8762

Academic Journal

10.1016/j.cherd.2019.06.026