During last 18 years (4 years pre-PhD + 14 years post-PhD), Dr. Gardas has gained considerable experience in the field of solution thermodynamics, fluid phase equilibria, measuring and predicting of physico-chemical properties, structure-property relations and physical chemistry of ionic liquids.

1. Thermodynamic and transport properties of several pure liquids and liquid mixtures of non-electrolyte compounds have been measured. Experimental data were used to get the insight into intermolecular forces and microscopic structure of liquids, which are also useful in the process and product design calculations involving separations, heat transfer, mass transfer, and fluid flow.

2. The Flory statistical theory and the ERAS (Extended Real Associated Solution) model were applied to estimate and interpret the volumetric properties of binary and ternary liquid mixtures.

3. Contributed in building high pressure measurement set-up for the density measurement as a function of temperature and pressure (J. Chem. Eng. Data 52 (2007) 737-751).

4. Earliest and timely study made on the high pressures density measurements for the series of ionic liquids in wide ranges of pressure and temperature and explained about the isothermal compressibility, isobaric expansivity and thermal pressure coefficient of ionic liquids. First paper of series of 5 papers on this work was published in J. Chem. Eng. Data in 2007 has been received more than 345 citations.

5. A new model was developed based on a QSPR approach for describing the densities in wide ranges of pressures and temperatures (Fluid Phase Equilib. 263 (2008) 26-32, Citations: 255+). This model is now widely known and cited as “Gardas and Coutinho Model”.

6. A number of other properties were also modelled with success such as viscosity, surface tension, speed of sound, heat capacity and parachor and papers on these subjects have been published in various journals with a success that can be measured by the number of citations these works achieved.

7. The mutual solubilities of water/organic liquid and ionic liquids have been studied, and with partition coefficients, in particular developing a new approach to the measurements of octanol-water partition coefficients that can produce, not only this most relevant information for the environmental fate of ionic liquids, but also relevant information on their ionization in organic solvents.