Gum Arabic Nanoparticles as Green Corrosion Inhibitor for Reinforced Concrete Exposed to Carbon Dioxide Environment

Mohammad Ali Asaad; Ghasan Fahim Huseien; Mohammad Hajmohammadian Baghban; Pandian Bothi Raja; Roman Fediuk; Iman Faridmehr; Fahed Alrshoudi

doi:10.3390/ma14247867

Gum Arabic Nanoparticles as Green Corrosion Inhibitor for Reinforced Concrete Exposed to Carbon Dioxide Environment

Materials (Basel). 2021 Dec 19;14(24):7867. doi: 10.3390/ma14247867.

Authors

Mohammad Ali Asaad¹, Ghasan Fahim Huseien², Mohammad Hajmohammadian Baghban³, Pandian Bothi Raja⁴, Roman Fediuk⁵, Iman Faridmehr⁶, Fahed Alrshoudi⁷

Affiliations

¹ Department of Civil Engineering, Iraq University College, IUC Al-Estiqlal St., Basra 61007, Iraq.
² Department of the Build Environment, School of Design and Environment, National University of Singapore, Singapore 117566, Singapore.
³ Department of Manufacturing and Civil Engineering, Faculty of Engineering, Norwegian University of Science and Technology (NTNU), 2815 Gjøvik, Norway.
⁴ School of Chemical Sciences, Universiti Sains Malaysia, Penang 11800, Malaysia.
⁵ School of Engineering, Far Eastern Federal University, 690091 Vladivostok, Russia.
⁶ Institute of Architecture and Construction, South Ural State University, Lenin Prospect 76, 454080 Chelyabinsk, Russia.
⁷ Department of Civil Engineering, College of Engineering, King Saud University, Riyadh 11421, Saudi Arabia.

Abstract

The inhibiting effect of Gum Arabic-nanoparticles (GA-NPs) to control the corrosion of reinforced concrete that exposed to carbon dioxide environment for 180 days has been investigated. The steel reinforcement of concrete in presence and absence of GA-NPs were examined using various standard techniques. The physical/surface changes of steel reinforcement was screened using weight loss measurement, electrochemical impedance spectroscopy (EIS), atomic force microscopy and scanning electron microscopy (SEM). In addition, the carbonation resistance of concrete as well screened using visual inspection (carbonation depth), concrete alkalinity (pH), thermogravimetric analysis (TGA), SEM, energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The GA-NPs inhibitor size was also confirmed by transmission electron microscopy (TEM). The results obtained revealed that incorporation of 3% GA-NPs inhibitor into concrete inhibited the corrosion process via adsorption of inhibitor molecules over the steel reinforcement surface resulting of a protective layer formation. Thus, the inhibition efficiency was found to increase up-to 94.5% with decreasing corrosion rate up-to 0.57 × 10^-3 mm/year. Besides, the results also make evident the presence of GA-NPs inhibitor, ascribed to the consumption of calcium hydroxide, and reduced the Ca/Si to 3.72% and 0.69% respectively. Hence, C-S-H gel was developed and pH was increased by 9.27% and 12.5, respectively. It can be concluded that green GA-NPs have significant corrosion inhibition potential and improve the carbonation resistance of the concrete matrix to acquire durable reinforced concrete structures.

Keywords: GA-NPs; carbonation resistance; depth carbonation; green corrosion inhibitor; morphology; rebar corrosion.