Nanofluids based on hydrolyzed polyacrylamide and aminated graphene oxide for enhanced oil recovery in different reservoir conditions

• Published in: Fuel (Guildford) 2022-02, Vol.310, p.122299, Article 122299
• Main Authors: de Vasconcelos, Cláudia K.B., Medeiros, Felipe S., Diniz, Bruna R.S., Viana, Marcelo M., Caliman, Vinicius, Silva, Glaura G.
• Format: Article
• Language: English
• Subjects: Aging; Chemical composition; Enhanced oil recovery; Enhanced oil recovery (EOR); Ethylenediamine; Graphene; Graphene oxide (GO); High temperature; Image transmission; Ionic strength; Nanofluids; Nanomaterials; Nanotechnology; Oil; Oil recovery; Oxidation; Partially hydrolyzed polyacrylamide (HPAM); Polyacrylamide; Reservoirs; Rheological properties; Salinity; Salinity effects; Viscosity
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2021.122299

•Nanofluids with 0.5% wt. and 1.0% wt. of GO and GOA-EDA were the most promising.•The greatest viscosities increase occur in the greatest ionic stretch.•The increased viscosity after 90 days of aging for 0.5% GO nanofluids was 104%•The increased viscosity after 90 days of aging for 1,0% GOA-EDA nanofluids was 146%•Nanofluids prepared with GOA-EDA showed better performances after 90 days. Partially hydrolyzed polyacrylamide (HPAM) aqueous fluids in reservoirs produces a significant increase in the produced oil volume. However, the viscosity of these fluids is highly influenced by the temperature and salinity of the medium which is crucial in some reservoir conditions for the oil recovery. Thus, addition of nanomaterials in HPAM solutions to prepare nanofluids has been shown to be a promising alternative to increase viscosity and improve the performance in enhanced oil recovery. In this work, graphene oxide (GO) was prepared using modified Hummers method through the oxidation/exfoliation of expanded graphite while the aminated graphene oxide (GOA-EDA) was prepared using ethylenediamine in an ultrasonic bath. Spectroscopic techniques, elementary and thermogravimetric analyses confirmed the chemical composition of the produced nanomaterials. Images obtained by transmission electron microscope also confirmed the interfacial interactions between GO / GOA-EDA and HPAM. Rheological measurements were performed to determine the nanofluids viscosity as a function of concentration at high temperature (70 °C) under different salinity conditions. The results indicate that the viscosity increases promoted initially by the nanofluids prepared with GOA-EDA were smaller than those obtained by the nanofluids prepared with GO. In particular, the greatest increases in viscosity values occurs in the medium with the highest ionic strength (ηi%μ=0.6>ηi%μ=0.3>ηi%μ=0.1). However, after 90 aging days, nanofluids prepared with GOA-EDA showed better performances reaching gains of up to 146% in viscositiy when compared to the HPAM reference fluids indicating that nanofluids prepared with GOA-EDA are more promising for application in enhanced oil recover.