Interaction and Adsorption of Hydrophobically Modified Polyacrylamide on Silica and Asphaltene Surfaces

Wenjie Zou,Zichuan Fang,Zhenzhen Lu,Zhijun Zhang

doi:10.1155/2019/5423178

Abstract

The adsorption of polymers affects the cost and oil recovery in oil reservoir exploitation and the flocculation effect in the treatment of oil sand tailings. The adhesion and adsorption of a hydrophobically modified polyacrylamide (HMPAM), i.e., P(AM-NaAA-C16DMAAC), on silica and asphaltene were investigated using surface force measurements, thermodynamic analysis and quartz crystal microbalance with dissipation (QCM-D) measurement. Our study indicates that HMPAM polymer has strong interaction with both silica and asphaltene. The adhesion force of HMPAM on silica was stronger than that on asphaltene surface. Consistently, the adsorption of HMPAM was also greater on silica surface, with a more rigid layer formed on the surface. For HMPAM/silica system, the attractive interaction and the strong adhesion are mainly driven by the hydrogen bonding and electrostatic interaction. For HMPAM/asphaltene system, it is mainly due to hydrophobic interaction between the long hydrocarbon chains of HMPAM and asphaltene. Furthermore, continuous adsorption of HMPAM was detected and multiple layers formed on both silica and asphaltene surfaces, which can be attributed to the hydrophobic chains of HMPAM polymers. This work has illustrated the interaction mechanism of HMPAM polymer on hydrophilic silica and hydrophobic asphaltene surfaces, which provide insight into the industrial applications of hydrophobically modified polymer.

Highlights

Special attention has been focused on the hydrophobically modi ed polyacrylamide containing relatively low amounts of hydrophobic monomers (~2mol%)
Due to the intramolecular and intermolecular interaction between the hydrophobic groups, the enlargement of hydrodynamic volume of polymers increases the viscosity of hydrophobically modi ed polyacrylamide aqueous solutions, and intermolecular association may further enhance the viscosity [10]. e aqueous solution of these polymers is expected to show special properties, including temperature, salt, and shear resistances [11, 12]. e viscosity of hydrophobically modi ed polyacrylamide solution does not decrease at high salinity when its concentration is larger than the critical aggregation concentration [13]
Our work revealed the fundamental interaction mechanisms between hydrophobically modi ed polyacrylamide (HMPAM) and silica and asphaltene surface, which will benefit the development of polymers in oil reservoir exploitation and oil sand tailings treatment

Summary

Introduction

Special attention has been focused on the hydrophobically modi ed polyacrylamide containing relatively low amounts of hydrophobic monomers (~2mol%). Due to the intramolecular and intermolecular interaction between the hydrophobic groups, the enlargement of hydrodynamic volume of polymers increases the viscosity of hydrophobically modi ed polyacrylamide aqueous solutions, and intermolecular association may further enhance the viscosity [10]. Advances in Polymer Technology polymer [17] Another kind of hydrophobically modified polyacrylamide with monomers of acrylamide and 2‐(methacryloyloxyl) ethylhexadecyldimethylammonium bromide displays the adsorption of multilayer on natural sand [18]. Hydrophobically modified polyacrylamide polymers have been applied in enhanced oil recovery (EOR) of oil reservoir exploitation [7, 22,23,24,25,26], emulsified oil removal from aqueous solution [27] and oil sand tailings treatment [28]. Our work revealed the fundamental interaction mechanisms between HMPAM and silica and asphaltene surface, which will benefit the development of polymers in oil reservoir exploitation and oil sand tailings treatment

Experimental

Results and Discussion

Summary and Conclusions