Influence of carbon quantum dots on the viscosity reduction of polyacrylamide solution

FUEL

卷:248

Article

Haruna, Maje Alhaji¹  Hu, Zhongliang¹  Gao, Hui¹  Gardy, Jabbar¹  Magami, Saminu Musa²  Wen, Dongsheng^1,3 

[1] Univ Leeds, Sch Chem & Proc Engn, Leeds LS2 9JT, W Yorkshire, England

[2] 17 Whinchat Ave, Newton Le Willows, Merseyside, England

[3] Beihang Univ, Sch Aeronaut Sci & Engn, Beijing 100191, Peoples R China

关键词: Rheology;    Reduced viscosity;    Polyacrylamide;    Carbon quantum dots;    Viscoelasticity;   

DOI  :  10.1016/j.fuel.2019.03.039

来源: Elsevier

【 摘 要 】

Viscosity is one of the key factors which influence the application of polyacrylamide (PAM) in enhanced oil recovery (EOR). In this study, we have demonstrated the viscosity reduction of PAM solution by using carbon quantum dots (CQDs) through rheological, spectroscopic and thermal analyses. The stability of PAM, CQDs, and PAM/CQDs composites, and the chemical interactions between PAM and CQDs were investigated. The addition of CQDs into PAM solution decreased its viscosity, demonstrating a phenomenon which contradicts the expression normally derived from the Einstein-Batchelor law for the viscosity of particle suspensions. Consequently, the elastic properties of PAM/CQDs composites were lower than those of the pure PAM solutions. Moreover, the presence of CQDs in the PAM increased its flow activation energy and decreased its yield point, leading to an increased sensitivity to both temperature and shear rate. The mechanism behind the reduced viscosity behaviour of PAM/CQDs composites appears to be the formation of free radicals and the elimination of ammonia molecules, leading to the deterioration of the polymer backbone.

【 授权许可】

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