Deep Eutectic Solvents with Dual Hydrogen Bond Donors

Department of Chemical Engineering, Universiti Teknologi PETRONAS, 32610 Bandar Seri Iskandar, Perak, 6 MALAYSIA 7 * Correspondence: [email protected]; Tel.: +60-53687623 8 9 10 Abstract: Deep eutectic solvents (DESs) are known as tunable solvents. It is possible to prepare 11 ternary deep eutectic solvent (TDES) are used for desired purpose by selecting the suitable molar 12 ratio and components of mixture. Therefore, four DESs and two TDESs were prepared in this work. 13 DESs and TDESs were prepared with potassium carbonate (PC) as a hydrogen bond acceptor (HBA) 14 and three hydrogen bond donors (HBDs) such as glycerol (GL), ethylene glycol (EG) and 2-amino15 2methyl-1-3-propanediol (AMPD) known as a hindered amine (HA). Binary DESs were PC-GL with 16 molar ratios 1:10 and 1:16 and PC-EG with the same molar ratios. TDES were prepared by adding 17 AMPD in binary DESs such as PC-GL-AMPD 1:16:1 and PC-EG-AMPD 1:10:1. The experimental 18 density and refractive index of all DESs and TDESs were measured at the temperature of 293.15 to 19 343.15 K with an interval of 5 K. The effect of temperature, molar ratio and alkyl chain length on the 20 properties was investigated. The molar volumes and isobaric thermal expansion were calculated 21 using experimental density data. The experimental refractive index data was used to derive the 22 specific refraction, molar refraction, free molar volume, electronic polarization, polarizability 23 constant and internal pressure at several temperatures. 24