CO₂ Capture in Ionic Liquids: A Review of Solubilities and Experimental Methods

Abstract

The growing concern of climate change and global warming has in turn given rise to a thriving research field dedicated to finding solutions. One particular area which has received considerable attention is the lowering of carbon dioxide emissions from large-scale sources, that is, fossil fuel power. This paper focuses on ionic liquids being used as novel media for CO2capture. In particular, solubility data and experimental techniques are used at a laboratory scale. Cited CO2absorption data for imidazolium-, pyrrolidinium-, pyridinium-, quaternary-ammonium-, and tetra-alkyl-phosphonium-based ionic liquids is reviewed, expressed as mole fractions (X) of CO2to ionic liquid. The following experimental techniques are featured: gravimetric analysis, the pressure drop method, and the view-cell method.

CO2 absorption studies in amino acid-anion based ionic liquids

“…Capture and Storage (CCS) is a promising approach to mitigate the CO 2 emissions into the atmosphere [1][2][3][4][5][6]. The CO 2 capture technologies are classified as Solvent absorption (physical and chemical), adsorption (physical and chemical), membrane and cryogenic separation.…”

Synthesis, characterization and application of 1-(2-cyanoethyl)-3-(3-methoxypropane)imidazolium bromide for CO2capture

“…The amount of gas sorbed was calculated from the initial measurement of temperature, volume and pressure and the final measurement of the variables at equilibrium. The calculation was done by converting all three variables into moles of gas using Peng-Robinson equation of state [11].…”

Carbon dioxide capture via aqueous N-methyldiethanolamine (MDEA)-1-butyl-3-methylimidazolium acetate ([bmim][Ac]) hybrid solvent

“…Aqueous hybrid solvents at 30 wt% N-methyldiethanolamine (MDEA) and 1-butyl-3-methylimidazolium acetate, [bmim][Ac] as ionic liquids (ILs) at concentration of 10 wt% and 20 wt% were formulated and its thermophysical properties were investigated as presented in our work elsewhere [8].CO 2 absorption capacity of aqueous hybrid solvent samples were investigated at three different pressures of 10 bar, 15 bar, and 20 bar while keeping the temperature constant at of 30°C using High Pressure Solubility Cell (HPSC). The HPSC mainly consists of one mixing vessel (MV), two equilibrium cell (EC 1 and EC 2 ), magnetic stirrer, pressure sensor, and gas storage tank.…”

“…In existing industrial absorption processes solvents that are widely and commercially applied for CO 2 absorption processes are alkanolamines or its mixture such as monoethanolamine (MEA), diethanolamines (DEA), methyldiethanolamine (MDEA), and Piperazine (Pz) [5,6]. However, amines have got certain limitations such as high regeneration cost (energy intensive), low loading capacity, equipment corrosion [7][8][9]. Use of ionic liquid (ILs) in small amount with amines as hybrid solvents is …”