Ilnaz T. Rakipov

Chemical evaluation and kinetics of Siberian, north regions of Russia and Republic of Tatarstan crude oils

ABSTRACT In this research, thermal characteristics and model free kinetics of five different °American Petroleum Institute gravity crude oil samples from different locations were studied using combustion calorimetry and thermogravimetry (TGA) techniques. Higher heating values of crude oils were determined from the combustion calorimetry experiments. It was shown that these values increase with an increase in saturate fraction and °API gravity of studied samples and decrease with an increase in viscosity, aromatics fraction, and resin fraction of crude oils. In thermogravimetry, experiments were performed at 10, 20, and 30°C/min heating rates under an air atmosphere. Thermal characteristics of the samples such as reaction intervals and corresponding peak temperatures, mass loss, and residue of the crude oil samples were also determined. Two different model free kinetic methods, known as Ozawa–Flynn–Wall (OFW) and Kissinger–Akahira–Sunose (KAS), were used in order to determine the activation energy values of the crude oil samples studied.

Characterization and Kinetics of Siberian and Tatarstan Regions Crude Oils Using Differential Scanning Calorimetry

In this study, nonisothermal kinetics and thermal analysis of Siberian and Tatarstan regions crude oils is studied by differential scanning calorimetry (DSC) at different heating rates. DSC curves revealed two reaction regions in the temperature range of 20–600°C, known as low and high temperature oxidation, respectively. Three different kinetic methods (ASTM, Borchardt and Daniels, and Roger and Morris) were used to determine the kinetic parameters of the samples and it was observed that the activation energy values are varied.

Thermodynamics of dissolution and infrared-spectroscopy of solid dispersions of phenacetin.

In this work enthalpies of dissolution in water of polyethylene glycols (PEGs) having an average molecular weight of 1000 and 1400, Pluronic-F127, phenacetin as well as the composites prepared from them were measured using solution calorimetry at 298.15 K. Intermolecular interaction energies of polymer-phenacetin were calculated on the basis of an additive scheme. It was shown that for mixtures with high content of polymer (>90 wt%) Pluronic-F127 has the highest solubilizing effect, while for mixtures with (4–6):1 polymer: phenacetin ratio the best solubilizing agent is PEG-1400. Infrared-spectra showed a decrease of the number of self-associated molecules of phenacetin with increasing of polymer content in the composites. The obtained results enabled us to identify the features of intermolecular interactions of polymers with a model hydrophobic drug and may be used for optimizing the conditions for preparing solid dispersions based on hydrophilic polymers.

Development of an Effective Scale Inhibitor Based on Organophosphonic Compounds in an Aqueous-Alcohol Solvent

We have studied the effect of the ratio of hydroxyethylidene diphosphonic acid and nitrilotri(methylphosphonic acid) and also polyaminopolyether methylenephosphonate chelating agent additives on scale inhibition in simulated formation water. We show that replacing the water with an aqueous-alcohol solvent lowers considerably the pour point of the reagent without having an appreciable effect on its effectiveness. We have developed a composition that exhibits high effectiveness of scale inhibition for scale composed of calcium carbonate and also calcium and barium sulfates when added at 10-20 mg/L.