Influence of Crude Oil Components on Interfacial Dilational Properties of Hydrophobically Modified Polyacrylamide

Abstract

The effects of acidic components and asphaltenes on the dilational rheological properties of hydrophobically modified polyacrylamide (APP5) have been measured as a function of the time, frequency, bulk concentration, and interfacial pressure by means of a drop shape analysis method. It is established that acidic components and asphaltenes play an important role on the interfacial properties of the APP5/crude oil component mixture at water–kerosene interface. With the addition of acidic components, the dilational modulus of the mixture not only increases with time but is also higher at low concentrations and runs through a maximum at a lower concentration compared to pure APP5. Also, the phase angle of APP5/acidic components is lower compared to pure APP5. The results indicate that the appearance of more elastic films because of the mixed adsorption of acidic components and APP5 molecules. The addition of asphaltenes does not influence the interfacial properties of APP5 at high APP5 concentrations. However, one can observe changes of the interfacial tension and the dilational modulus with the addition of asphaltenes at lower APP5 concentrations. It can be concluded that the behaviors of interfacial layers of the APP5/asphaltene mixture are controlled by APP5 molecules in competition with the asphaltenes at the interface.

Effect of partially hydrolyzed polyacrylamide on emulsification stability of wastewater produced from polymer flooding

“…A remarkable increase in HPAM adsorption will occur with the increase of HPAM concentration, resulting in the increasing dilational viscosity. With the further increase of the concentration, the fast exchange process between the network structure and HPAM monomer near the interface will destroy the rigid structure, reducing the dilational viscosity (Hu et al, 2015). At higher frequency, the dilational viscosity decreases slowly with increasing HPAM concentration from 300 to 500 mg/L (Fig.…”

“…The dilational viscoelasticity (includes dilational modulus, dilational elasticity and dilational viscosity) is an important property of fluid interface, which plays a significant role in emulsion stability (Hu et al, 2015). The interfacial dilational viscoelasticity depends upon interfacial or near interfacial microrelaxation processes.…”

“…This will decrease the interfacial tension gradients and cause a decrease of the dilational modulus. On the other hand, the interfacial excess increases with increasing the bulk concentration as well, leading to higher interfacial tension gradients and an increase of the dilational modulus (Zhang et al, 2008;Hu et al, 2015). Thereupon, the dilational modulus runs through a maximum as a function of the bulk HPAM concentration.…”

“…HPAM contains a small fraction of hydrophobic groups. The hydrophobic chains developing intermolecular hydrophobic associations may form a network structure, leading to a significant increase in viscoelasticity (Hu et al, 2015). At low HPAM concentrations, larger vacancies between polymer molecules exist at the interface, because there are not enough HPAM molecules in the interface to completely cover the interfacial area.…”

Laboratory Study on the Oil Displacement Properties of Sugar Amine Sulfonate Surfactant

“…The light components are the main ingredient in oil (1) and oil (2) while oil (3) mainly contains heavy components. The reason for the low IFT between oil (4) and SAS solution was that oil contained more medium chain components which matched with the hydrophobic group of SAS, effectively contributing to form a stable interface [32,33].…”