Studies on Equation of State for Applications to Pure Compounds and Mixtures

Abstract

First Chapter introduces the basic aspects of Equations of State (EOS) in general and cubic Equations of State (CEOS) in particular. Chapter provides the details about the aim and the scope of the work. Chapter two is devoted to literature survey. The chapter starts with basic information on EOS and CEOS. Chapter discusses literature pertaining to modifications in CEOS, modifications in cohesion factor expression for both Peng Robinson (PR) and Soave Redlich Kwong (SRK). It also presents varios methods for estimation of different properties using CEOS. This chapter provides the background of the work done so far and also provides the pit falls of the existing models. Chapter three describes various procedures for developing new cohesion factor expression. The chapter starts with describing a simple technique for developing expression of cohesion factor. Compound-specific cohesion factors are developed next for both PR and SRK EOS. These models are generalized for various families. Chapter also provides the details about overall generalization. Two approaches are discussed, perturbation and empirical approach. The empirical approach adds reduced dipole moment and critical compressibility factor as the third parameter in the cohesion factor expression. Fourth Chapter deals with describing algorithms for predicting various properties like, vapour pressure, molar volume, departure functions, second virial coefficient, boiling point, heat capacity, using CEOS. Chapter also discusses the algorithm for obtaining viii binary interaction parameters (BIP) from VLE data and procedure for predicting isothermal VLE data. It also gives some idea about the codes developed in the present work. Basic information on the MATLAB® (software used) is also provided in the Chapter. Chapter five reports the predicted values of various properties discussed in Chapter four. Comparison of existing cohesion factor models with proposed models is discussed. The exercise is done for both PR and SRK EOS. The proposed models were compared based on percent absolute average deviation of various properties. The results show that the proposed models having reduced dipole moment perform better for many properties. Final chapter summarizes the work and also tabulates the best cohesion factor models to be used with SRK and PR EOS based on the outcome of the study. It also outlines the future possible work in the area. Information pertaining to various data base used during the studies and some mathematical derivations are provided in various appendices. One of the appendices is also devoted to describing various codes developed in the present study. The Thesis also has the CD containing the entire database in the excel format as well as in .mat format of MATLAB. All the codes developed during the work in .m files of MATLAB are also provided in the CD. Research publications out of the study are also provided on the CD ROM.