ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

A computational and experimental investigation of novel synthesis fused pyrazolopyrimidine as zinc corrosion inhibitor in 1 M HNO₃

Ghalia A. Gaber, Aisha Y. Hassan, Mona S. Kadh, Nashwa M. Saleh, Eman S. Abou-Amra, and Amira M. Hyba

Department of Chemistry, Faculty of Science (Girls), Al-Azhar University, Cairo, Egypt

E-mail: ghaliaasaid@azhar.edu.eg

Received: 3 October 2023  Accepted: 2 January 2024

Abstract:

Two compound derived from fused Pyrazolo-Triazolo-Pyrimidine (C1 and C2), have inhibitory action against corrosion of Zinc in 1 M HNO₃ examined experimentally by electrochemical tests and theoretically by density functional theory (DFT). The findings demonstrate that zinc corrodes in acidic conditions with greater corrosion resistance than C1 and C2. Concentration and corrosion inhibition directly relate to one another. The two Pyrazolopyrimidine-derived compounds had optimum inhibition efficiency of 92.06 and 79.36% for C1 and C2, respectively, at 700 ppm. In accordance to the polarization curves, the antagonists feature a mixed but primarily anodic inhibitor and a Langmuir process. DFT computations validated the compounds apparent antagonistic response. SEM also show the development of a barrier on the zinc surface. In conclusion, these two antagonists, C1 and C2, are successful in avoiding zinc dissolution in HNO₃.

Keywords: Corrosion; Inhibitors; Pyrazolopyrimidine; Characterization; Molecular modeling

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03303-x

Chemical Papers 78 (5) 3189–3203 (2024)