Kinetics, Thermodynamics, and Mechanism of a Novel Biphasic Solvent for CO₂ Capture from Flue Gas

Abstract

The main issue related to the deployment of the amine-based absorption process for CO capture from flue gas is its intensive energy penalty. Therefore, this study screened a novel biphasic solvent, comprising a primary amine e.g., triethylenetetramine (TETA) and a tertiary amine e.g., N, N-dimethylcyclohexylamine (DMCA), to reduce the energy consumption. The TETA-DMCA blend exhibited high cyclic capacity of CO absorption, favorable phase separation behavior, and low regeneration heat. Kinetic analysis showed that the gas- and liquid-side mass transfer resistances were comparable in the lean solution of TETA-DMCA at 40 °C, whereas the liquid-side mass transfer resistance became dominant in the rich solution. The rate of CO absorption into TETA-DMCA (4 M, 1:3) solution was comparable to 5 M benchmark monoethanolamine (MEA) solution. Based on a preliminary estimation, the regeneration heat with TETA-DMCA could be reduced by approximately 40% compared with that of MEA. C NMR analysis revealed that the CO absorption into TETA-DMCA was initiated by the reaction between CO and TETA via the zwitterion mechanism, and DMCA served as a CO sinker to regenerate TETA, resulting in the transfer of DMCA from the upper to lower phase. The proposed TETA-DMCA solvent may be a suitable candidate for CO capture.

Comparative Study between Pristine Ag and Ag Foam for Electrochemical Synthesis of Syngas with Carbon Dioxide and Water

“…Potential conversion to a RHE scale and iR u corrections were made to assess the activity and selectivity of the electrode on the same bias, as shown in Equation (3).…”

“…The exponential increase in anthropogenic carbon dioxide (CO 2 ) emissions to the Earth's atmosphere, has become one of the most urgent problems for the human society [1,2]. Many feasible methods for decreasing the concentration of CO 2 in the atmosphere have been carried out, such as CO 2 capture, utilization and storage [3][4][5][6][7][8][9]. Among these methods, the conversion of CO 2 to useful chemicals with the aid of renewable energy sources (wind, solar, tidal, etc.)…”

Application of the Thermodynamic Cycle to Assess the Energy Efficiency of Amine-Based Absorption of Carbon Capture

“…Table 1 summarizes the energy performance of three kinds of new amine-based solvents. [29,31] A blend of amines solvents integrates the properties and advantages of various amines, such as a classic combination of primary amines (e.g., MEA) or secondary amines (e.g., DEA) mixed with tertiary amines (e.g., MDEA) [32,33]. The performance of this kind of solvent, which combines the high reaction rate of primary or secondary amines with the high absorption capacity and lower absorption heat of tertiary amines, has been tested at the pilot scale or even higher scales for many years [34,35].…”

Detailed performance model of carbon dioxide absorption utilizing titanium dioxide nanoparticles in a wetted wall column

“…The post-combustion solvent based process is one of the most developed know-how for CO 2 mitigation [5][6][7]. The deployment of phase-splitting phenomenon and carbonic anhydrase enzyme technology has been intensively investigated [8][9][10].…”