Saccocalyx satureioides as corrosion inhibitor for carbon steel in acid solution

Abstract

The inhibitory effect of the crude ethyl acetate extract of Saccocalyx satureioides was estimated on the corrosion of carbon steel (X52) in 1 M HCl solution sing weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy and scanning electron microscopy techniques. Potentiodynamic polarization curves indicated that the plants extract behaves as a mixed-type inhibitor. The adsorption of the inhibitor on the carbon steel surface was found to follow Freundlich adsorption isotherm. The free energies, enthalpies and entropies for the adsorption and dissolution process were discussed in details. The inhibiting action increases with increasing concentration of the extract. The results obtained show that the extract of the aerial parts of Saccocalyx satureioides could serve as an effective corrosion inhibitor of carbon steel (X52) in hydrochloric acid medium.

Evaluation of Castor Bark Powder as a Corrosion Inhibitor for Carbon Steel in Acidic Media

“…Finally, an inhibitory efficiency of 83% was determined for the highest amount of castor bark powder added (1.77 g.L -1 ) to the HCl 0.5 mol L -1 , which is compatible with results available for others green inhibitors 10,29,31 as well as determined for other castor oil compounds [20][21][22] . However, in accordance with the adsorption isotherm calculations, the results showed a decrease of the inhibition efficiency with immersion time, indicating that the castor bark powder can be used only in applications where long immersion periods are not required.…”

“…The results displayed in Table 1 show that the inhibition efficiency of castor bark powder against AISI 1020 carbon steel corrosion increases up to 83% when 1.77 g.L -1 was added to the solution. Several scientists in their studies reported similar results for green inhibitors 4,10,[30][31][32][33] . The maximum values achieved are also compatible with those found for other castor oil compounds [20][21][22] .…”

“…It should be noted that the unit of C H2O lies in that of K 10,29 . A negative ∆G°a ds suggests that the adsorption of the inhibitor to the substrate surface is spontaneous.…”

“…Because of this, researchers have been focused in investigating the inhibitory properties of easily available and low cost natural products that, in addition, are not harmful to health and to the environment, which are generally denominated green inhibitors 6 . In the literature, several studies are available on the efficiency of leaves or peel extracts as corrosion inhibitors for carbon steel in acidic solutions (generally electrolyte prepared using 37% m/v HCl), like aqueous extracts of mango and orange peel 2 , and alcoholic extracts of Astemisia Mesatlantica oil 7 , Roselle 8 , Eruca sativa 9 , Saccocalyx satureioides 10 , Argemone mexicana 6 , Chrysophyllum albidum 11 , Agavoideae 12 , Tiliacora accuminata 13 , Pimenta dioica 14 , Ilex paraguariensis 15 , Aniba rosa eodora 16 , Ruta chalepensis 17 .…”

Acetohydroxamic acid adsorbed at copper surface: electrochemical, Raman and theoretical observations

“…0.0452), with the linear correlation coefficient R 2 = 0.9999. In addition, the standard free energy of adsorption, DG 0 ads , is obtained from the following equation [46] The large negative value of DG 0 ads indicates that AHA was strongly adsorbed on the copper surface [47,48]. Figure 8a, b illustrates the normal Raman spectrum of AHA powder and SERS spectrum of the AHA-modified copper electrode formed in 10 mM AHA solution for 3 h assembly time, respectively.…”