Electrochemical Analysis and Quantum Chemistry of Castor Oil-Based Corrosion Inhibitors

Biodiesel from “Morelos” Rice: Synthesis, Oxidative Stability, and Corrosivity

“…From the phase angle spectrum, it is possible to observe only part of the characteristic shape (Gauss bell shape) of the phase angle corresponding to one single time constant. However, the width of this time constant suggests that there are actually two overlapping time constants which evolve from the high frequency region to the intermediate frequency region; something similar has been reported when an oily film is adsorbed by the metal surface [54][55][56][57]59]. Therefore, the response observed in the region of high frequency (>1000 Hz, phase angle maximum practically constant and close to 90 ∘ ) represents the capacitive response of biodiesel, and that observed in the intermediate frequency region (10-1000 Hz, phase angle maximum variable) is due to the corrosion process in the steel-biodiesel interface [60].…”

“…However, due to the high resistivity of biodiesel, it is not obvious to associate such response with the corrosion processes at the metal-electrolyte interface [20]. However, despite this, the analysis of the Bode diagram can differentiate the capacitive response of biodiesel from the response of the stainless steel corrosion process [54][55][56][57][58]. From the phase angle spectrum, it is possible to observe only part of the characteristic shape (Gauss bell shape) of the phase angle corresponding to one single time constant.…”

Oil Extraction from “Morelos Rice” Bran: Kinetics and Raw Oil Stability

“…Surprisingly, in this study the FFA content was estimated at 8.15%, an interesting result considering that the rice bran was collected few hours after the milling process. As such, this degradation level limits rice bran for food purposes but also offers possible applications in the synthesis of chemical products, as biodiesel and corrosion inhibitors [18][19][20][21][22][23][24]. The iodine index is associated with the degree of unsaturations in the oil and indicates the capacity of being oxidized because of the unsaturations present in its hydrocarbon chains.…”

Fatty Amides from Crude Rice Bran Oil as Green Corrosion Inhibitors

“…In the particular case of environments where the presence of hydrocarbons predominates, the inhibitors based on amide-or imidazolines-type compounds are widely used [3][4][5][6][7][8][9]. The excellent performance of this type of corrosion inhibitors is associated with the fact that its molecules are constituted by two essential parts: an electronrich polar part capable of adhering onto a metal surface through coordination bonds and a hydrophobic part which can effectively prevent the diffusion of contaminants present in the aggressive environment [2,5,[9][10][11][12]. In addition to the above, it has also been reported that the presence of unsaturation or other functional groups of the alkyl chains also influences their inhibition efficacy [7,9,13].…”

“…The excellent performance of this type of corrosion inhibitors is associated with the fact that its molecules are constituted by two essential parts: an electronrich polar part capable of adhering onto a metal surface through coordination bonds and a hydrophobic part which can effectively prevent the diffusion of contaminants present in the aggressive environment [2,5,[9][10][11][12]. In addition to the above, it has also been reported that the presence of unsaturation or other functional groups of the alkyl chains also influences their inhibition efficacy [7,9,13]. These characteristics are provided by the nature of the vegetable oil used for the synthesis of this type of inhibitors.…”