Temperature dependent physicochemical and spectroscopic (FT-IR) studies of citrate salts (trilithium citrate and triammonium citrate) in aqueous ionic liquid [C4mim][BF4] (1-butyl-3-methyl imidazolium tetrafluroborate) solutions

Study on the volumetric and compressibility properties of citrate salts trilithium citrate (TLC) and triammonium citrate (TAC) in (0.005, 0.01, 0.03 and 0.05) mol kg−1 aqueous solutions of ionic liquid [C4mim][BF4] at 5 K intervals, from 288.15 K to 308.15 K and experimental pressure p = 0.1 MPa, are performed to understand the intermolecular interactions existing in the system. We have utilized the experimental data of density and speed of sound for determining the apparent molar and partial molar parameters concerning volumetric and compressibility properties at the investigated temperatures. The structure making or breaking ability of ionic liquid has been discussed in terms of sign of (∂2Vϕ0/∂T2). Other parameters like partial molar volumes of transfer and partial molar isentropic compression of transfer demonstrate in terms of hydrophilic- hydrophilic, hydrophilic-hydrophobic, hydrophobic-hydrophobic interactions. Fourier transform infrared spectroscopy (FTIR) was employed to acquire information about the interaction between the citrate salts (TLC, TAC) and ionic liquid [C4mim][BF4]. The results have been discussed in terms of interactions existing among citrate salts and ionic liquid solutions.