DEEP EUTECTIC SOLVENT FOR CO2 CAPTURE: CHOLINIUM CHLORIDE WITH PHENYLACETIC ACID SYSTEM

Abstract

Global warming is one of the most pressing challenges that face societies these days. As result, worldwide public attention has risen due to the serious greenhouse gas effect, which causes detrimental environmental effects such as climate change. Carbon dioxide emission is considered as one of the most significant greenhouse gases activity involved in climate change. In power plants, these gases especially carbon dioxide are emitted by fossil fuels; therefore, capturing it will reduce the greenhouse effect. Increasing energy demand is triggering increased usage of fossil based fuels, which cause unprecedented toxic gaseous emissions to atmosphere. Release of these gases is harmful to environment, especially CO2 as it increases the acidity and salinity of fresh and sea/ocean water sources. Due to increased global risk in caused by the toxic emissions, several options have been considered in both political and academic platforms in order to find feasible and sustainable emission control models. CO2 capture contributes to three fourths of the overall gaseous emissions capture activities and it has a cumulative negative cost side effect of 50% increase in electricity production in related industries. The choice of the suitable technology differs on the characteristics of the gas stream in which CO2 will be captures. Such characteristic depends on the type of the dynamics of the process through which the fuel is processes and used. Deep Eutectic Solvents (DESs) are a novel, advanced class of solvents, which maintain the most relevant characteristics of ionic liquids (ILs), but can be prepared using a more facile and inexpensive method. This alternative approach is based on producing eutectic mixtures of salts and hydrogen-bonding donors (HBDs). The purpose behind this study is to examine a new system of DES system which is Choline chloride/ Phenylacetic acid (ChCl/PAA) for CO2 capture. The CO2 solubility as function of temperature and pressure, with other relevant physicochemical properties including density, conductivity, corrosion, surface tension, Fourier Transform Infrared (FTIR) and Thermogravimetric analysis (TGA) characterizations are reported to analyze DES system and its capability for capturing the CO2. Experimental studies of DES that reported in this work showed that this sort of eutectic solvents have appreciable performance of CO2 at low corrosion effect in compared with monoethanolamine (MEA). CO2 absorption estimated by studying the behavior of the liquid –gas and interface properties. CO2/N2 solubility values were determined using high magnetic sorption apparatus (MSA) of Rubotherm at temperature 298.15 up to 338.15 K and pressure up to 30 bars. It’s conclude that the ChCl/PAA DES system with molar ratio of 1:2 absorbed 2.10 mmol/g of CO2 at 308.15 K and 30 bar, with the same conditions ChCl/ Levulinic Acid system absorbed the same amount of CO2, while ChCl/ethylene glycol absorbed 3.1265 mmol/g of CO2 at 303.15 K and 58.63 bars. The amount of absorption of ChCl/PAA increase to 3.35 mmol /g of CO2 by increasing the molar ratio to 1:3 at the same temperature and pressure of the 1:2 molar ratio . In compared with amine based, solid amine sorbent, consisting of poly (ethylenimine) (PEI) absorbed 2.8 mol/kg of CO2 at 353.15 K and partial pressures more than 10kPa (0.1 bar). Moreover, in compared with the most known amine in industry MEA, DES (1:3) at 30 bars and 308 K absorbed 3.35 mmol/g CO2 while MEA at 24 bars and 313 K absorbed 2.66 mmol/g CO2. The non-toxic, low cost and the other advantages of reported eutectic solvent with favorable physical properties offers an environmentally promising alternative for effective CO2 capture technological applications.