Inhibition of Aluminium Corrosion in Hydrochloric Acid Using Nizoral and the Effect of Iodide Ion Addition

The effect of nizoral (NZR) on the corrosion inhibition of aluminium alloy AA 1060 in 2 M HCl solution was investigated using the mylius thermometric technique. Results of the study revealed that nizoral acts as corrosion inhibitor for aluminium in the acidic medium. In general, at constant acid concentration, the inhibition efficiency increases with increase in the inhibitor concentration. The addition of KI to the inhibitor enhanced the inhibition efficiency to a considerable extent. The adsorption of nizoral onto the aluminium surface was found to obey the Fruendlich adsorption isotherm. The value of the free energy for the adsorption process shows that the process is spontaneous

INHIBITORY EFFECT AND ADSORPTION CHARACTERISTICS OF 2,3-DIAMINONAPHTHALENE AT ALUMINUM/HYDROCHLORIC ACID INTERFACE: EXPERIMENTAL AND THEORETICAL STUDY

The inhibitive effect of 2,3-diaminonaphthalene (2,3-DAN) for corrosion of aluminum in 1 M HCl was investigated using hydrogen evolution technique at 30 and 40°C. Quantum chemical calculation results showed that 2,3-DAN molecule possessed planar structure with a number of active centers, which aided the adsorption process. The Mulliken charge density, the highest occupied molecular orbital (HOMO), and the lowest unoccupied molecular orbital (LUMO) were found mainly focused around nitrogen atoms and the cyclic of the benzene as well. The presence of 2,3-DAN molecules in the corrosive medium (1 M HCl solution) inhibits the corrosion process of aluminum and as the concentration of 2,3-DAN increases the inhibition efficiency also increases but decreases with rise in temperature. The corrosion inhibition of 2,3-DAN was discussed in terms of blocking of the Al surface by adsorption of the molecules of the inhibitor at the active centers. It was found that the adsorption of 2,3-DAN onto the Al surface followed the Langmuir adsorption isotherm and 2,3-DAN adsorbed on Al surface probably by physisorption. The proposed physisorption mechanism was supported by the calculated values of Ea, Qads, and ΔGads.2,3-diaminonaphthalene, aluminum, corrosion inhibition, adsorption isotherm, quantum chemical studies, Austin Model 1 (AM1)

Phytochemical and Antimicrobial Properties of Leaves of Alchonea Cordifolia

The phytochemistry of Achornea cordifolia leaf extract using different solvents was studied using standard methods. The effects of the leaf extract on some pathogenic bacteria and fungi were also examined. The Phytochemical screening of the leaves shows the presence of useful ethno-botanical bioactive substances such as tannin, saponin, flavonoid, cardiac glycoside and anthraquinone, while alkaloid, phlobatanin and terpene also tested for were absent. The butanol fraction of the extract gives the highest zone of inhibition (13.0 mm) against Staphylococcus aureus, Escherichia coli and pseudomonas aeruginosa, which are in parity. The control, gentamycin injection gives 12.5 mm, 11.0 mm and 12.0 mm respective zones of inhibition against the Staphylococcus aureus, Eschariclia coli and Pseudomonas aeruginosa. Also, the butanol fraction of the extract shows highest zone of inhibition of 17.0 mm against Candida albican, while ethanolic extract gives 13.0 mm zone of inhibition against Trichophyton violaceum