Fast screening of amine/physical solvent systems and mass transfer studies on efficient aqueous hybrid MEA/Sulfolane solution for postcombustion CO₂ capture

Abstract

BACKGROUND: The addition of a physical solvent to a traditional chemical absorbent has been shown to improve the absorption and desorption performance of the absorbent system. This type of novel absorbent system combining a single physical solvent with an amine solvent is a promising development in the industrial application of CO 2 capture. RESULTS: Hybrid solutions composed of Monoethanolamine (MEA), a physical solvent, and H 2 O were comprehensively investigated using the rapid solvent screening apparatus and a VLE apparatus. The results show that 30 wt% MEA with 20 wt% Sulfolane and 50 wt% H 2 O achieved higher rich loading, strong cyclic CO 2 capacity and the highest desorption rate over a wide range of CO 2 loadings. Also, the mass transfer performance of CO 2 absorption into the 30 wt% MEA and 20 wt% Sulfolane solution was investigated in a lab-scale random packing column. The effects of liquid flow rate, liquid feed temperature, lean CO 2 loading, inert gas flow rate and CO 2 partial pressure on the mass transfer performance were evaluated in terms of volumetric overall mass transfer coefficient (K G a v ). Furthermore, a correlation was developed for CO 2 absorption into MEA/Sulfolane solution in a random packing column using semi-empirical models as functions.CONCLUSION: Unlike for amine solution alone, inert gas flow rate is an indispensable operating parameter in the MEA/Sulfolane system. A mass transfer correlation model was established and holds significance in studying the kinetics of CO 2 absorption by a mixture of physical and chemical solvents and for the optimal design of Dixon-ring random packing columns. Industry ratus shown in Fig. 1. From the beginning of this experiment, a water saturation chamber and a reactor loaded with 15 mL hybrid solution were put into the water bath with the temperature kept at 313.15 K. Then a gas blend of CO 2 and N 2 with CO 2 partial pressure J Chem Technol Biotechnol 2020; 95: 649-664

Eco-Friendly Deep Eutectic Solvents Blended with Diethanolamine Solution for Postcombustion CO2 Capture

“…In the case of glyceline–DEA hybrid solvents, the CO 2 capacities remain relatively unchanged with glyceline concentration and the values are approximately equal to the CO 2 capacity of the blank DEA solvent. However, at low CO 2 partial pressures typical of postcombustion carbon capture, where the chemical absorption is dominant, partial or total replacement of water with a non-volatile physical solvent mostly leads to a lower CO 2 solubility. − For instance, Skylogianni et al measured the solubility of CO 2 in MDEA–MEG–H 2 O systems and they observed that at a constant amine concentration, the absorption capacity clearly decreases with increasing glycol content at low partial pressures of CO 2 . Babamohammadi et al have reported the CO 2 solubility data in Gly–MEA solutions; increasing the Gly concentration from 5 to 20 wt % decreases the CO 2 capacity from 0.56 to 0.51 mol CO 2 /mol MEA, a decrease by ∼9%, at a temperature of 40 °C and a CO 2 partial pressure of 15 kPa.…”

Effect of Fly Ash on the Mass Transfer Performance of CO2 Removal Using MEA and DEA Solutions in a Packed Tower

“…Consequently, the effective gas-liquid contact area (a v ) increases, and there is more thorough contact between the gas and the liquid. Furthermore, increasing the liquid/gas ratio (L/G) not only results in an increase in the liquid-side mass transfer coefficient (k L ) but also leads to a decrease in the thickness of the liquid film, particularly when the mass transfer is controlled by the liquid phase [29,38,39]. As a result, K G a v increases rapidly.…”

Low-Viscosity Nonaqueous Sulfolane–Amine–Methanol Solvent Blend for Reversible CO2 Capture

“…It is a polar aprotic solvent with a strong affinity for acid gases. , Sulfolane enhances CO 2 absorption rate and solubility during the chemical absorption without participating in the chemical reaction . In a recent article by Zou et al, it was shown that the addition of sulfolane enables higher absorption and desorption rates and higher cyclic capacity in CO 2 capture in comparison to the aqueous MEA. A study on the sulfolane-based semiaqueous piperazine (PZ) system concluded that addition of sulfolane increased the equilibrium constant at medium CO 2 loadings and slightly increased the CO 2 cyclic capacity .…”