In this work the likelihood of asphaltene deposition problems during dynamic displacement of oil by natural gas in unconsolidated porous media is experimentally inspected. The two different rock materials, limestone and sandstone, are used as a representative of porous media. Dynamic flow experiments indicate that the increase of natural gas injection inc...

the basics of quantum mechanics and statistical thermodynamics were used to predict the potential energy and intermolecular forces of asphaltene molecules. the parameters associated with the chemical structure were also estimated for a specific asphaltene molecule to predict the mie potential function. based on the structural results, a new form of the virial eos with peneloux correction was de...

The deposition of asphaltenes in porous media, an important problem in science and macromolecular engineering, was for the first time investigated in a transparent packed-bed microreactor (μPBR) with online analytics to generate high-throughput information. Residence time distributions of the μPBR before and after loading with ~29 μm quartz particles were measured using inline UV-Vis spectrosco...

This study investigates the effect of surface acidity and basicity of aluminas on asphaltene adsorption followed by air oxidation. Equilibrium batch adsorption experiments were conducted at 25°C with solutions of asphaltenes in toluene at concentrations ranging from 100 to 3000 g/L using three conventional alumina adsorbents with different surface acidity. Data were found to better fit to the F...

The basics of quantum mechanics and statistical thermodynamics were used to predict the potential energy and intermolecular forces of asphaltene molecules. The parameters associated with the chemical structure were also estimated for a specific asphaltene molecule to predict the Mie potential function. Based on the structural results, a new form of the Virial EOS with Peneloux correction wa...

Onset of asphaltene precipitation is the key parameter in dealing with asphaltene problems because it is the starting point of the asphaltene separation from the solution. In this study, a new technique is provided based on the experimental observations for the determination of the onset of asphaltene precipitation using accurate density measurements of the crude oils upon titration with precip...

The use of nanoparticles, including metal oxide surfaces, as asphaltene adsorbents is a potential method of removing and/or upgrading asphaltenes. The adsorption of two asphaltene types, extracted from two types of Iranian crude oil, onto nanoparticles (TiO2, SiO2, and Al2O3) are assessed and the thermal behavior of the adsorbed asphaltenes is examined under an oxidizing atmosphere through ther...

this paper is concerned with asphaltene deposition in fluid flowing through pipelines. brownian diffusion and drag, gravitational, thermophoresis, buoyancy, and shear removal are considered as possible mechanisms in the asphaltene deposition process. the thermo-physical properties of the fluid were obtained from iranian oil fields. a model was used in the pipeline deposition modeling to predict...

this study has been investigated, the effects of three different polar polyacrylamides (anionic, cationic, and nonionic) on asphaltene deposition in porous media. all experiments were carried out in various dead oil flow rates (0.2, 0.1 and 0.02 cc/min) and different polymer concentrations (500, 2500, 4000 ppm). the results indicated that asphaltene precipitation was affected by the presence of...

The molecular-mass distribution of the asphaltene fraction of petroleum is rapidly becoming more constrained, but themolecular architecture remains poorly understood. Two types of molecular structures have been proposed to be representative of asphaltenes: the “island” model and the “archipelago” model. Here, nine compounds were synthesized on the basis of pyrene, representing both types of mod...