Abstract
A series of anion-nonionic hyperbranched surfactants HPSA were prepared by grafting the N-lauryl-monoamido sulfosuccinic acid onto hydroxyl-terminated hyperbranched polyamide ester (HP). The optimum grafting condition was obtained by single-factor experiments when the mole ratio of HP and N-lauryl-monoamido sulfosuccinic acid was 1:5. The molecular structure of HPSA-5 were characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy and gel permeation chromatograph. Furthermore, the wettability, surface activity and emulsifying ability of the prepared surfactant were studied. The results showed that HPSA-5 solution had good potential on change of wettability. Surface activity studies showed that HPSA-5 was temperature-resistant and salt-tolerant capacity of 140 °C and ρ(NaCl) = 2 × 105 mg/L, ρ(CaCl2) = 1.5 × 104 mg/L, respectively. In the heat aging experiment (under the temperature of 120 °C and the NaCl of 105 mg/L for 12 hours), the surface tension of HPSA-5 were almost unchanged. The salt tolerence of 0.3 g/L HPSA-5 was superior to 0.3 g/L SDS and 0.3 g/L OP-10 at the ability of emulsifying Tahe crude oil (China, Xinjiang) at 120 °C. The result of the sandpack model crude oil displacement experiments showed that 1.5 g/L HPSA-5 could further increase the crude oil recovery to 10.27%, compared with 6.44% crude oil recovery for 0.6 g/LSDS + 0.9 g/L OP-10 after water flooding.
Graphical Abstract
Disclosure statement
No potential conflict of interest was reported by the authors.