Electrochemical, Spectrochemical and Quantum Chemical Studies on Dimedone as Corrosion Inhibitor for Copper in Acetonitrile
Journal Title: Journal of Scientific Research and Reports - Year 2017, Vol 15, Issue 2
Abstract
The inhibition ability of 5,5-Dimethyl-1,3-cyclohexanedione (dimedone, DMD) for copper in acetonitrile at 25°C was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Corrosion resistance increased with inhibitor concentration up to 93.68% inhibition efficiency at 3.00 mM, indicating that DMD molecules can cumulatively adsorb on the copper surface and finally form a protective film on copper-solution interface. This is also supported by the decreasing of copper oxidation in cyclic voltammogram. Polarization curves revealed that DMD is of mixed type inhibitor. The adsorption of DMD on copper surface obeys the Langmuir isotherm and the adsorption mechanism is of physisorption type. The standard energy of adsorption (∆Goads) values was found in good agreement for both polarization and impedance to be -8.17 and -8.43 kJmol-1 respectively. Fourier Transform Infrared spectroscopy (FT-IR) confirmed the interaction of copper with oxygen on DMD. The mole ratio method suggested that the complexation ratio of copper-DMD is 1:2. Scanning electron microscopy (SEM) of copper surface after immersion in DMD solution indicates the presence of a protective layer on the electrode surface. The frontier molecular orbital energy EHOMO (highest occupied molecular orbital), ELUMO (lowest unoccupied molecular orbital) and the Mulliken charge distribution obtained from Quantum chemical calculations revealed (∆E) for DMD 0.2091 hartree, reflecting strong adsorption of the molecules on copper surface. The enhanced corrosion inhibition is possibly due to the compact film structure blocking electron transfer at the electrode surface.
Authors and Affiliations
Pipat Chooto, Sontaya Manaboot
Keywords
Related Articles
- EP ID EP323368
- DOI 10.9734/JSRR/2017/34929
- Views 96
- Downloads 0
Biomarker Characteristics of Crude Oil Blends from Some Flow-Stations in Bayelsa State, Nigeria
Three different crude oil samples from three crude oil flow stations in Bayelsa state, Nigeria, were chosen for this study and were used to analyze the geochemical characteristics such as thermal maturity, depositional e...
Taste Evaluation of Rice Grown in Soil Treated with Commercial Silica and Recycled Rice Husk Silica
Aim: To evaluate the taste of rice grown in soil treated with rice husk silica in order to elucidate the potential use of rice husk silica as a fertilizer in terms of taste of rice. Study Design: Rice plants were grown...
Analysis of Candidates’ Performance in Unified Tertiary Matriculation Examinations (UTME) and Post-UTME in the University of Ibadan, Nigeria
A major criterion for determining the eligibility of candidates for admission into Nigerian Universities was their performance in UTME and Post-UTME before the scrap of the Post-UTME in 2016. This study was therefore aim...
Comparitive Evaluation of Different Fungicides against Phytophthora infestans (Mont.) de Bary. Causing Late Blight of Potato
Aim: Evaluation of various fungicides and their effectiveness at different doses against Phytophthora infestans, the causal pathogen of late blight disease of potato. Study Design: Descriptive statistics was use...
Blending Formal Rules with Value Based Approaches toward Building Ethical Culture in Tanzania
Over the years, Tanzania government has strived towards establishing ethical culture in the public service. One of the methods used by the government since the attainment of its independence is the establishment of prope...