Testing and Comparing the Inhibitory Action of Red Onion Seeds and Peels Extracts on the Corrosion of Steel in Phosphoric Acid

Abstract

The inhibitory action of Red onion seeds and peels extracts (ROSE & ROPE) was testing and comparing on the corrosion of steel in 0.75 M H 3 PO 4 using chemical measurements (hydrogen evolution, HE and mass loss, ML) and SEM technique. The effect of temperature on the corrosion of steel in 0.75 M H 3 PO 4 without and with certain concentration of each extract was studied in the temperature range of 303-333 K. Generally, the inhibition efficiency (i.e. surface coverage) increases with extracts concentration and fits the Langmuir adsorption isotherm. The results of HE, ML and SEM showed that ROSE has a capability to protect steel surface in 0.75 M H 3 PO 4 more than ROPE. Good agreement between HE and ML measurements was obtained. Temperature coefficients without and with each extract revealed somewhat chemisorptive and physiosorptive behavior of ROSE and ROPE, respectively. Good correlation between the major effective constituents of each extract and the inhibition mechanism was obtained.

A study of the gorse aqueous extract as a green corrosion inhibitor for mild steel in HCl aqueous solution

“…These results show that the presence of the gorse extract changes the electrical doublelayer structure, intending that the inhibitory molecules act by adsorption at the metal/solution interface. The adsorption of an organic adsorbate between the metal/solution interface can be considered as a replacement adsorption process between the organic molecules in the aqueous solution Org (soln) and the water molecules on the metal surface H 2 O (ads) (12,31):…”

“…From the electrochemical impedance data, it was possible to determine the degree of coverage of the metal surface (θ) as a function of inhibitor concentration. The experimental results were adjusted to different adsorption isotherms (Langmuir, Temkin, Flory-Huggins and El-Awady according to the following equations (12,31,38,39):…”

“…Langmuir's theory admits that adsorption occurs at a specific and homogeneous site and each inhibitory molecule holds only one site (31). The Temkin isotherm assumes that the heat of adsorption of all the molecules covering the adsorbent decreases linearly as a function of the coating due to the interactions between the adsorbed molecules (a > 0, attraction, <0, repulsion) (12,31).…”

Spectral investigation of the Piperazine Dithiosemicarbazone Derivatives as inhibitor on High Carbon Steel in HCl media

“…According to Noor [45], ∆G ads value was less than-20kJ mol -1 it leads to physisorption,more than -40kJ mol -1 chemisorption. In our study ∆G ads value of the C1, C2 were around -34 to -36 kJ mol -1 .…”

Corrosion Inhibition of Aluminum by Psidium Guajava Seeds in HCl Solution

“…The fat contains 11.8% saturated fatty acids and 87.3% unsaturated fatty acids, 0.1% myristic, 6.6% palmatic, 4.6% steric, 10.8% oleic, 76.4% lineolic, 0.3% arachidonic acid and 0.1% linolonic acid [11][12][13][14][15]. The major constituents in Psidium guajava contain nitrogen and oxygen compounds, and some investigations showed their adsorptive property over metal surface and anticorrosive behavior [16][17][18][19][20]. The structure of some chemical constituents is as it follows:…”