Ziziphus Spina Christi Leaves Methanol Extract Evaluation as Antifungal, Antibacterial, Antioxidant and Green Inhibitor for Carbon Steel Alloy Corrosion in Hydrochloric Acid

In this study, Zs-c leaves were extracted by a 70% CH 3 OH solvent. The extract was investigated as green corrosion inhibitor for CS C1010 alloy in 0.1 M HCl. The study was done with different inhibitor concentrations (1, 2, 8 and 9 ppm). The extract showed the highest IE of 96.06%, at 9 ppm. The inhibitor adsorption on the CS alloy surface was found to obey the Langmuir’s adsorption isotherm model. K ads , ΔH ads , ΔS ads and ΔG ads were also calculated. The temperature effect on Zs-c leaves extract IE%, with the optimal concentration of 9 ppm, was studied at 35,45 and 55 ºC. The results showed that IE% decreased with raising solution temperatures. In addition, 𝐸 (cid:3028)∗ , ΔH, ΔS and ΔG kinetic parameters were calculated. On the other hand, phytochemical tests and quantitative analysis, such as TPC and TFC, were also carried out. In addition, the anti-bacterial activity or growth inhibition of bacterial strains, such as Ec and Sa, were studied. Anti-fungal activity or growth inhibition studies of Ca and An species were also carried out, at a 100 mg/mL concentration. Anti-oxidant activity was also investigated by DPPH, at concentrations of 100, 250, 500, 750 and 1000 µg/mL, and good results were obtained.