Experimental and Theoretical Investigation of the Inhibitor Efficiency of Eucalyptus globulus Leaf Essential Oil (EuEO) on Mild Steel Corrosion in a Molar Hydrochloric Acid Medium.

As a corrosion inhibitor for mild steel in a molar hydrochloric acid medium, we investigated the potential of Eucalyptus globulus essential oil (EuEO). Through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves, and theoretical methods, including DFT/B3LYP 6-31G (d, p) and Monte Carlo simulations, the interactions between the EuEO components and the steel surface were analyzed. D-Allose, Betulinaldehyde, and Uvaol were identified as the major active compounds in the GC-MS analysis. The experimental results showed that EuEO reached an inhibitory efficiency as high as 97% at a 1 g/L concentration. The findings suggest that EuEO operates as a mixed-type inhibitor, reducing both cathodic and anodic reactions, as well as building up a protective coating on the steel surface. Simulations also confirmed that EuEO molecules function as electron donors and acceptors, enhancing corrosion resistance.

Elaboration of an innovative plant biomaterial for its valorization in the treatment of wastewater.

The global scientific community is deeply concerned about the deterioration of water quality resulting from the release of industrial effluents. This issue is of utmost importance as it serves to safeguard the environment and combat water pollution. The objective of this work is to elaborate a biomaterial of vegetable origin, based on the twigs of Aleppo pine, and to use it as an abundant and less expensive material for the treatment of wastewater. For this reason, the twigs were treated physically to get the powder called biomaterial FPA (Aleppo pine fiber), which was characterized by physicochemical, and spectroscopic analyses namely scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The crystallinity index of FPA was evaluated by the peak height method. The findings indicate that the FPA powder has an acidic nature, exhibiting a porous structure that promotes the adsorption and binding of molecules. Additionally, it has a zero charge point of 5.8 and a specific surface area of 384 m2.g-1. It is primarily composed of hydroxyl, carboxyl, and amine functional groups, along with mineral compounds and organic compounds, including cellulose and other mineral elements such as Ca, Mg, Fe, Na, P, Al, K, Ni, and Mo. Combining these characteristics, FPA biomaterial has considerable potential for use as an effective adsorbent biomaterial for various wastewater pollutants. Its abundance and relatively low cost make it an attractive solution to the growing challenges of water pollution worldwide.