Glory and Praise to Jehovah, the all mighty God who allowed me to achieve this research work. I e... more Glory and Praise to Jehovah, the all mighty God who allowed me to achieve this research work. I express my utmost gratitude to Prof. Deresh Ramjugernath for his dedicated supervision and his priceless assistance throughout this study. Dr Paramespri Naidoo, the co-supervisor is sincerely acknowledged for her pertinent suggestions and skillful guidance.
Experimental Hydrate Phase Equilibrium Data Relevant to Bitter Melon, Pineapple, and Grape Juice Concentration
ACS Omega
A new group-interaction contribution method to predict the thermal decomposition temperature of ionic liquids
Chemometrics and Intelligent Laboratory Systems, 2016
An enhanced group-interaction contribution method for the prediction of glass transition temperature of ionic liquids
Fluid Phase Equilibria, 2016
Assessing hydrate formation as a separation process for mixtures of close-boiling point compounds: A modelling study
Journal of Natural Gas Science and Engineering, 2016
Experimental Phase Equilibrium Measurements for the (ethane + ethylene) Binary Clathrate Hydrates
Hydrate phase equilibria in mixtures of close-boiling point compounds: Experimental and modeling studies
A Multi-Phase-Multi-Component Clathrate Hydrate Phase Equilibrium Model
A molecular-based model for prediction of liquid viscosity of pure organic compounds: A quantitative structure property relationship (QSPR) approach
Journal of the Taiwan Institute of Chemical Engineers, 2013
Ionic liquids: Prediction of melting point by molecular-based model
Thermochimica Acta, 2012
ABSTRACT The aim of is this study is to develop molecular-based model for prediction of melting p... more ABSTRACT The aim of is this study is to develop molecular-based model for prediction of melting points of diverse classes of ionic liquids. For this purpose, exhaustive literature survey was conducted in order to collect comprehensive database of the melting points of ionic liquids. The melting points of 808 diverse ionic liquids belongs to Sulfonium, Ammonium, Pyridinium, 1,3-Dialkyl imidazolium, Tri-alkyl imidazolium, Phosphonium, Pyrrolidinium, Double imidazolium, 1-Alkyl imidazolium, Piperidinium, Pyrroline, Oxazolidinium, Amino acids, Guanidinium, Morpholinium, Isoquinolinium and Tetra-alkyl imidazolium have been collected from 131 various references. Quantitative Structure–Property Relationship (QSPR) approach was applied in order to develop a reliable model for the prediction of the melting points of ionic liquids. As far as the authors concern, the investigated data has the broadest range of anion and cation structures among the previous studies which enhances its generality to predict melting point of unknown ionic liquids. The final QSPR model derived by Genetic Function Approximation (GFA) contains 12 descriptors and quantified by the following statistical parameters: R2train = 0.658, R2test = 0.721 and Average Absolute Relative Deviation (AARD) = 7.3%. The Applicability Domain (AD) of the model is also investigated. It turns out that the model's domain is defined broadly enough to contain all the trained and test sets which verified the reliability of the model. Finally, the proposed model has been scrutinized by several validation techniques and its robustness and reliability is investigated. The results of the validation techniques indicate the present model is robust, stable and reliable one.
Prediction of surface tension of ionic liquids by molecular approach
Journal of Molecular Liquids, 2013
ABSTRACT Originally, Quantitative Structure Property Relationship (QSPR) models for the surface t... more ABSTRACT Originally, Quantitative Structure Property Relationship (QSPR) models for the surface tension of ionic liquids are developed based on molecular descriptors. A large data set of 930 experimental surface tension data points for 48 ionic liquids is applied to derive the model. Seven descriptors are selected by genetic function approximation to relate the surface tension of ionic liquids to their corresponding anions and cation structures. To capture the nonlinear nature of surface tension, a model based on Least-Squared Supported Vector Machine (LSSVM) is also developed. The derived models are authenticated with several statistical validation techniques.
Dissociation Data and Thermodynamic Modeling of Clathrate Hydrates of Ethene, Ethyne, and Propene
Dissociation conditions for simple and mixed hydrates of ethane and ethene (ethylene) have been m... more Dissociation conditions for simple and mixed hydrates of ethane and ethene (ethylene) have been measured using the isochoric pressure-search technique. Simple hydrate dissociation data for ethane and ethene measured in this work are compared to existing literature data. The agreement between the measured ethane hydrate dissociation data with the literature data is acceptable while some deviations between the measured ethene hydrate dissociation data and those reported in the literature are observed. All new data for simple and mixed hydrates of ethene and ethane are well-correlated using an empirical correlation proposed by Adisasmito and coworkers. However, agreement between the experimental data with the predictions of the CSMGem model is found to be unsatisfactory. A gas chromatography technique combined with the isochoric-pressure search method is used to measure composition of the vapor phase in equilibrium with the hydrate and aqueous phases inside the hydrate stability region. The feed compositions investigated were 0.174, 0.420, and 0.810 mole fractions of ethane. In addition, dissociation points were found to be in the vicinity of the ethane hydrate dissociation conditions regardless of the initial content of ethane in the feed. It was also found that temperature does not have a considerable effect on ethane content of the vapor phase in equilibrium with hydrate and aqueous phases inside the hydrate stability region at given pressures.
Phase Equilibria of Clathrate Hydrates of Ethyne + Propene
Journal of Chemical & Engineering Data, 2014
ABSTRACT In this communication, experimental dissociation data for mixed ethyne (acetylene) and p... more ABSTRACT In this communication, experimental dissociation data for mixed ethyne (acetylene) and propane hydrates are reported in the temperature and pressure ranges of (274.6 to 280.8) K and (0.250 to 1.280) MPa, respectively. Moreover, three-phase equilibrium conditions inside the hydrate stability region with compositional analysis are reported in the temperature and pressure ranges of (275.6 to 278.9) K and (0.392 to 0.894) MPa. Experimental ethyne mole fractions at equilibrium on a water free basis ranged between 0.053 and 0.523. The van der Waals and Platteeuw solid solution theory, together with the Valderama-Patel-Teja equation of state and nondensity dependent mixing rule were combined to model phase equilibria of clathrate hydrates of ethyne + propane. The proposed modeling approach was found to be reliable as good agreement was observed between the experimental and predicted data for this system.
Phase equilibria of methane and carbon dioxide hydrates in the aqueous MgCl2 solutions
Fluid Phase Equilibria, 1998
ABSTRACT
Activity coefficients at infinite dilution of organic solutes in the ionic liquid 1-ethyl-3-methylimidazolium methanesulfonate
Ionic liquids, owing to their unique characteristics grasp many researchers' attention in both ac... more Ionic liquids, owing to their unique characteristics grasp many researchers' attention in both academia and industrial fields. In this communication, the attention is focused on the heat capacity of ionic liquids, as one of the most basic and important thermophysical properties. The simple 5-term temperature dependent correlation based on basic molecular parameters is presented to predict heat capacities of ILs. A total data set of 2940 experimental data belonging to 56 ionic liquids was used to develop a general correlation. The global absolute average deviation of the model results from experimental values is 2.5%. The proposed model could be safely applied for thermodynamic and industrial applications.
A group contribution method for estimation of glass transition temperature ionic liquids
Chemical Engineering Science, 2012
ABSTRACT In this study, a new accurate model is presented for estimation of the glass transition ... more ABSTRACT In this study, a new accurate model is presented for estimation of the glass transition temperature of ionic liquids. To develop this simple model, the contribution of ILs’ anions and cations are separately considered through a number of occurrences of 50 substructures (17 anion-based and 33 cation-based). This simple model shows a low average relative deviation (AARD) of 3.65% for a data set including 496 (396 for training and 100 for validation) experimental glass transition temperature. Furthermore, the predictive power of the model is evaluated using the NIST Standard Reference Database #147 data. The model shows an AARD% of 4.3%.
Activity coefficients at infinite dilution for ternary system
AIChE Journal, 1972
... data such as total pressure-concentration curve ( P - z), bubble point-concentration curve (2... more ... data such as total pressure-concentration curve ( P - z), bubble point-concentration curve (2' - x) and dew point-concentration curve (T - y, or P - y), has been proposed by Carlson and Colburn (5), Redlich and Kister (13), Gautreaux and Coates (7), and Ellis and Jonah (6), and ...
Tumba, K.; Hashemi, H.; Naidoo, P.; Mohammadi, A. H.; Ramjugernath, D., (2015), Phase Equilibria of Clathrate Hydrates of Ethyne + Propene, Journal of Chemical & Engineering Data, 60, 217-221.
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