
This paper introduces Supercritical Fluid and the factors are considered why it is used for Extraction. This describes the classification and study of various models used for predicting solubility of solid solutes in Supercritical Fluid. Correlating and Predicting of solid solubility can be done by Semi-empirical Equations and different Equations of State. Due to the various limitations of empirical equations a more exact approach is to treat the calculation of solubility in a supercritical fluid just as any other phase equilibrium calculation. Thermodynamic equilibrium is assumed to exist between the two phases, thus, they are assumed to be at the same temperature and pressure. Further, the chemical potential (or equivalently, the fugacity) of each component must be equal in each phase. Cubic Equations of State cannot be applied for associating molecules so we are approaching molecular thermodynamics which include SAFT(Statistical association Fluid Theory) and ESD(Elliott-Suresh-Donohue ). For all these we need various physical parameters like Tc, Pc, ω, Ps at for some solid solute it is given in the literature but for complex solutes like pharmaceutical drugs and dyes etc. It is not given in literature so we will calculate it by various different Group Contribution Methods like Joback’s , Constantino-Gani method, Ambrose-method, Lydersen Method. I had done this for various solutes. I had done calculation for pharmaceutical drugs like Flubiprofen, Ketoprofen, Naproxen, Ibuprofen and various anthraquione dyes and its derivatives