%0 Journal Article %T Phase Behaviour of 1-Ethyl-3-methylimidazolium Thiocyanate Ionic Liquid with Catalytic Deactivated Compounds and Water at Several Temperatures: Experiments and Theoretical Predictions %A Ramalingam Anantharaj %A Tamal Banerjee %J International Journal of Chemical Engineering %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/209435 %X Density, surface tension and refractive index were determined for the binary mixture of catalytic deactivated compounds with 1-ethyl-3-methylimidazolium thiocyanate at temperature of (298.15 to 323.15) K. For all the compounds with ILs, the densities varied linearly in the entire mole fraction with increasing temperature. From the obtained data, the excess molar volume and deviation of surface tension and refractive index have been calculated. A strong interaction was found between similar (cation-thiophene or cation-pyrrole) compounds. The interaction of IL with dissimilar compounds such as indoline and quinoline and other multiple ring compounds was found to strongly depend on the composition of IL at any temperatures. For the mixtures, the surface tension decreases in the order of: thiophene > quinoline > pyridine > indoline > pyrrole > water. In general from the excess volume studies, the IL-sulphur/nitrogen mixture has stronger interaction as compared to IL-IL, thiophene-thiophene or pyrrole-pyrrole interaction. The deviation of surface tension was found to be inversely proportional to deviation of refractive index. The quantum chemical based COSMO-RS was used to predict the non-ideal liquid phase activity coefficient for all mixtures. It indicated an inverse relation between activity coefficient and excess molar volumes. 1. Introduction Zero emission of nitrogen and sulphur in diesel oil production is one of the largest challenges for petroleum refineries in the world. However the hydrodenitrification (HDN) and hydrodesulphurization (HDS) processes represent an even more important challenge. Most of the refineries in the world are able to produce diesel oil with above 70£¿ppm of nitrogen [1] and 500£¿ppm of sulphur [2] by using high hydrogen consumption, large reactor volume, and severe operating conditions [3]. Thus the refinery must remove the aromatic compounds of nitrogen/sulphur such as pyrrole, indole, indoline, carbazole, benzocarbazole, pyridine, quinoline, benzoquinoline, thiophene, benzothiophene, dibenzothiophene, and their derivatives [1, 2, 4]. Moreover the catalysts having higher activity or selectivity do not interact favourably with such compounds, even at moderate temperatures [5]. On the other hand the nature of the compounds coupled with its chemical structure posseses more sterical hindrance as compared to the catalysts. The HDN and HDS processes have greater ability in removing nonaromatic structure of nitrogen and sulphur molecules from diesel oil with high efficiency although not economically [6, 7]. Over the past few years %U http://www.hindawi.com/journals/ijce/2011/209435/