β-Cyclodextrin-Functionalized Hydrophobically Associating Acrylamide Copolymer for Enhanced Oil Recovery

Abstract

Acrylamide copolymer in the chemical flooding process plays a significant role in the field of tertiary recovery for enhanced oil recovery. Allyl-β-cyclodextrin and octadecyl dimethyl allyl ammonium chloride are utilized to react with acrylamide to synthesize a novel cyclodextrin-functionalized hydrophobically associating acrylamide polymer (HCMPAM) by redox freeradical polymerization. The microstructure of HCMPAM is the spatial network characterized by Fourier transform infrared spectroscopy and atomic force microscopy, and the thermal stability of HCMPAM is investigated by thermal gravimetic analysis. In the performance evaluation experiments, HCMPAM demonstrates superior properties compared to the high molecular weight partially hydrolyzed polyacrylamide on the aspects of salt tolerance, temperature resistance, shear resistance, and surfactant compatibility. It was found that the viscosity of 2000 mg/L HCMPAM reaches a maximum at 80 °C, and it could maintain 45.7% viscosity retention rate at 120 °C under the conditions of 20000 mg/L NaCl, 2000 mg/L CaCl 2 , and 10 s −1 shear rate. The viscosity can recover immediately with a slight decrease to the primary value during repeated revisable shear (100 s −1 −0). In addition, the flooding mechanism of mixed flooding of HCMPAM and surfactant is put forward by the interaction between them. The simulative tertiary oil recovery tests signify that HCMPAM can remarkably enhance 5.7−9.4% of oil recovery ratio, especially while HCMPAM is used after HPAM flooding. These features indicate that HCMPAM has a great potential application for enhanced oil recovery, especially in high-temperature and high-mineralization oil fields.

A double‐tailed acrylamide hydrophobically associating polymer: Synthesis, characterization, and solution properties

“…However, the viscosity rose from 189.9 to 237.4 mPa s between 8 and 80 g/L which showed an obvious salt thickening phenomenon attributed to the hydrophobic association. 34 It was also important to note that the scope of salt thicken was wider than other literature reports 35 which showed an excellent property of salt resistance. After that the size of polymer chains were reduced by electrostatic shield and the salt thickening phenomenon disappeared after increasing the concentration of NaCl solution further.…”

“…The increased EOR was due to the thickening efficiency of the supramolecular structure formed by hydrophobic association, which could increase the molecule hydrodynamic volume. 35 The tertiary oil recovery tests C, the concentration of polymer solutions; V, the pore volume of cores; E 1 , the oil recovery ratio by water flooding; E 2 , the total oil recovery ratio by water flooding and polymer flooding; EOR 5 E 2 2E 1 . demonstrated that the synthetic DTHAP exhibited better flooding effectiveness certainly and had potential application for enhanced oil recovery.…”

Modification of a nicotinic acid functionalized water‐soluble acrylamide sulfonate copolymer for chemically enhanced oil recovery

“…30,38 Shear Tolerance of the Copolymers The shear tolerance of the copolymers (2.0 g/L) was investigated, as shown in Figure 7(a). It was clear that the apparent viscosity of the copolymers decreased sharply under a shear rate of 3.7-200 s…”

Associating Polymer Networks Based on Cyclodextrin Inclusion Compounds for Heavy Oil Recovery

“…This work is one of the few [19,20] that attempts to use efficient thickening supramolecular systems formed by the host-guest interaction between WSHAPs and CD polymers for EOR. The main purpose of this work is to assess the performance of the proposed supramolecular system in heavy oil recovery.…”