Prediction of Density,Surface Tension,and Viscosity of Quaternary Ammonium-Based Ionic Liquids ([N222(n)]Tf2N) by Means of Artificial Intelligence Techniques

In this work, thermophysical properties of quaternary ammonium-based ionic liquids (ILs) including density, surface tension, and viscosity are produced by two powerful artificial intelligence techniques: genetic function approximation (GFA) and artificial neural network (ANN). In proposed GFA and ANN models, the critical temperature and water content of studied ILs ([N_222(n)]Tf₂N with n = 5, 6, 8, 10, and 12) as well as operation temperature were given as the input parameters and the density, surface tension, and viscosity were predicted as the output results. The obtained results reveal that the selected input parameters are appropriate for prediction of thermophysical properties of quaternary ammonium-based ILs. In addition, the high statistical quality represented by various criteria and the low prediction errors of the presented models indicate that they can accurately predict the density, surface tension, and viscosity of new ILs without recourse to experimental data.     

Applying a Smart Technique for Accurate Determination of Flowing Oil-Water Pressure Gradient in Horizontal Pipelines

Two-phase flow of liquids in pipelines is crucial subject in many industries such as chemical and petroleum. Accurate prediction of pressure gradient will lead to a better design of an energy efficient transportation system. Although numerous studies for prediction of two-phase flowing pressure drop have been reported in the literature, the accurate prediction of this parameter has been a topic of debate in many research areas. In this article, a novel model based on least square support vector (LSSVM) was proposed for calculation of two-phase flowing pressure drop in horizontal pipes. The inputs of this model are oil and water superficial velocities, pipe diameter, pipe roughness, and oil viscosity. To develop and test the model, more than 700 experimental dataset from open literature were utilized. The results of proposed model were compared against the well-known empirical correlations. Statistical error analysis showed that the LSSVM model outperforms existing predictive models. Finally, an outlier diagnosis was performed to detect the doubtful experimental.      

Mechanistic Simulation Studies on Viscous-Elastic Polymer Flooding in Petroleum Reservoirs

Based on the theory and application developments of polymer flooding on enhancing oil recovery, an improved mathematical model has been developed to simulate the mechanism of viscous-elastic polymer flooding. IMPES method has been presented to solve the polymer flooding model considering the viscosifying effect of elasticity, the effect of decreasing residual oil and the degradation of polymer molecules. The validation of the model is approved by an experiment. A simulation example was carried out using the developed numerical simulator. The enhanced oil recovery mechanism was discussed for viscous-elastic polymer flooding, and corresponding influencing factors were also studied.     

Dispersion Property of CO2 in Oil. Part 3: Aggregation of CO2 Molecule in Organic Liquid at Near Critical and Supercritical Condition of CO2

To study the dispersion property of CO₂ in organic liquids, the solubility of CO₂, the volume of CO₂ + organic liquids under different pressure at 318.15 K were measured and the radial distribution function of CO₂ molecule aggregate in the organic liquids was calculated by molecule dynamic simulation. The results show that the aggregate of CO₂ molecules in the organic liquids is formed obviously; the aggregation and disperse property of CO₂ molecule in the organic liquids is affected by the structure and polarity of the organic molecule at near critical and supercritical condition of CO₂ dominantly.     

Mechanistic Investigation on Dynamic Interfacial Tension Between Crude Oil and Ionic Liquid Using Mass Transfer Concept

Ionic liquids (ILs) are a new kind of solvents that have recently gained an upsurge in attention in light of their unique potential for different applications. With respect to this, in the present study, applicability of an IL called 1-octadecyl-3-methylimidazolium chloride ([C18mim] [Cl]) as a new class of surfactant was investigated. Different interfacial tension (IFT) measurements were performed to find the effect of IL concentration and temperature on the IFT of water/crude oil system. The observed trend was explained based on mass transfer mechanisms including diffusion and convective mass transfer. In addition, the effect of rotational speed, ranging between 3000 and 9000 rpm, on the IFT was examined with the hypothesis that it can modify the convective mass transfer. Finally, since it has been reported that the Marangoni effect enhances the mass transfer flux in the surfactant solutions, two different methods of IFT measurements including the spinning drop and pendant drop methods were applied to investigate the effects of convective mass transfer on the equilibrium IFT.     

Impact of Various Parameters Over the Stability of Water-in-Vegetable Oil Emulsion

Theory regarding emulsification, its coalescence and impact of emulsifier over its stability has been updated. For the verification of the proposed theory, water-in-oil emulsion was prepared by mixing water and soybean oil in the presence and absence of emulsifier, monoglyceride. The effect of different parameters like emulsification time, contents of water, and concentration of emulsifier has been investigated on the emulsification and coalescence process of the emulsion. It was noted that the emulsion quality was highest if the mixture was homogenized for about 15 minutes and the water contents were 40% v/v. The addition of monoglyceride up to 0.5% w/v gave the most stable emulsion having higher quality than other composition. The results obtained were compared with the proposed theory and found to have good compositions.      

Experimental and Theoretical Study of MTBE Adsorption from Polluted Water on GAC and PAC in Continuous Process

Methyl tertiary butyl ether (MTBE) is an organic compound thatis used to increase the gasoline octane number. At the beginning of 1980s, by discovering the undesirable effects of tetra ethyl lead usage in fuel, MTBE began to be used worldwide. But gradually the undesirable effects of MTBE on environment had been revealed. Adsorption is the most conventional and economical technology for MTBE removal from polluted water. In this research, some experiments have been done for studying the adsorption of MTBE on different solid adsorbent in continuous processes. In continuous experiments, the water polluted with known initial MTBE concentration passes through an adsorption column containing two kinds of adsorbent including granular activated carbon (GAC), powdered activated carbon (PAC). By measuring MTBE concentration in exit flow at different times the effect of different operating parameters such as temperature, pH, and flow rate have been studied and the optimum condition have been determined. The batch experimental results have been used to calculate the constant parameters of Langmuir adsorption isotherm equations. A dynamic simulation of MTBE adsorption on activated carbon in an adsorption column has been proposed. The comparison of the experimental data with the values given by the proposed model for similar operating conditions, verifies the accuracy of the proposed mathematical model.      

1-Hexyl-3-Methylimidazolium Chloride-Potassium Carbonate Aqueous Two Phase System: Equilibrium Characteristics and BSA Partitioning Behavior

The partitioning behavior of the model protein (bovine serum albumin) was investigated in ionic liquid (1-hexyl-3-methylimidazolium chloride) -salt (potassium carbonate) based aqueous two phase system (ATPS). The phase diagram with binodal curve and tie lines for the selected ATPS was developed at different temperatures and analyzed through effective excluded volume (EEV) and Othmer-Tobias and Bancroft equations, respectively. The influence of various process parameters like the ionic liquid and salt concentration, system temperature, tie line length, phase volume ratio, and neutral salt addition on partition coefficient/extraction efficiency of BSA protein was evaluated.     

Supported absorption of CO2 by tetrabutylphosphonium amino acid ionic liquids

A new type of "task specific ionic liquid", tetrabutylphosphonium amino acid [P(C4)4][AA], was synthesized by the reaction of tetrabutylphosphonium hydroxide [P(C4)4][OH] with amino acids, including glycine, L-alanine, L-beta-alanine, L-serine, and L-lysine. The liquids produced were characterized by NMR, IR spectroscopies, and elemental analysis, and their thermal decomposition temperature, glass transition temperature, electrical conductivity, density, and viscosity were recorded in detail. The [P(C4)4][AA] supported on porous silica gel effected fast and reversible CO2 absorption when compared with bubbling CO2 into the bulk of the ionic liquid. No changes in absorption capacity and kinetics were found after four cycles of absorption/desorption. The CO2 absorption capacity at equilibrium was 50 mol % of the ionic liquids. In the presence of water (1 wt %), the ionic liquids could absorb equimolar amounts of CO2. The CO2 absorption mechanisms of the ionic liquids with and without water were different.