PSI - Issue 72

Khedim Fatima Zahra et al. / Procedia Structural Integrity 72 (2025) 479–490

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been conducted utilizing concentration range of CP extract was 50 to 300 ppm and different temperatures 25 to 45 °C. Polarization studies proved that, this extract plays as a mixed - type inhibitor.The protection acts among adsorption phenomenon and creation of barrier film. The SEM and AFM images of the copper samples displayed that the copper was protected in the existence of the CP extract. The best percentage found is 82.8 % for 300 ppm at 25 °C obtained from the Weight Loss.been observed that the roughness rise in the existence of (HNO3) by Atomic Force Microscopy (AFM) Analysis because of the corrosion reaction, but in the existence of the CP extract the roughness were lowered due to the adsorption of the extract on the Cu surface, creating a defensive layer, representative that the Cu surface was became more smoothly and the consumption rate was diminished.Same withThe SEM micrographs of Cu surface alone and after 24 h dipping in 2.0 M HNO3 with and without addition of 300 ppm is displayed. In add 300 ppm of CP a metallic surface is clear, while in the absence of CP extract, the Cu is scratched by HNO3 corrosion. also, we noted that creation of a thin film of CP extract detected in SEM micrograph, thus defensive the surface versus corrosion. Haruna et al. (2021) evaluated the effect of Calotropis Procera (CP) extract on the corrosion inhibition of 304 stainless steel (SS) in 2 M HCl was studied using a concentrations 5 to 30 ppm, and temperature 25 to 45 °C. The adsorption of extract depends on its concentration, temperatures and the natural of the extract and metal. Reached the best percentage 79.1 % for 30 ppm at 25 °C obtained from the Weight Loss. Was observed between the values obtained by the weight loss and electrochemical measurements. Results obtained from Potentio-dynamic polarization indicated that CP extract is mixed-type inhibitor. Also, CP follows the formation of a physical adsorbed film on the metal surface. Table.2: green corrosion inhibitors by “ Calotropis procera ” extracts for the last years

Type of inhibitor

Type of solution

Ref.; year

Plant parts

Type of steel

Inhibitor concentration, temperature

Adsorption mechanism

Efficiency (%)

Testing methods

95.09 % at 1000 ppm at 2 hours of immersion for extraction method with methanol 78.1% at 1000 ppm at 4 hours for extraction method withChloroform 76 % at 1000 ppm at 2 hours for hot Water extract 40 Methyl-2 Phenylindole; 5,12Naphthace-nedione and 8-ethyl 60.01% for 0.4 M HCl at 8000 ppm without KI and 96.92 % with 0.5M KI

200, 400, 600, 800 and 1000 ppm

Physical Adsorption

Swasti et al. (2022)

Stem Pig iron 1M HCL

Mixed

WL

Priya and Jadonet (2021)

Physical adsorption

flowers Mild steel

1M HCL -

Mixed

DFT, MD,MC

0.2,0.4,0.6 and0.8 g/50 cm 3 (g/0.05L) (4000,8000, 12000 and 16000ppm)+ 0.1,0.2, 0.3, 0.4 and 0.5KI 50,100,150,200,250,300 ppm; 25, 30, 35, 40 and 45 °C

0. 1 , 0 . 2, 0.3 and 0.4M HCl

physical adsorption

Abdellattif et al. (2021)

Mixed

Thermo-metric studies

Leaves Mild steel

82.8 % for 300 ppm at 25 °C

WL, EIS, EFM,SEM, PP, AFM

Physical adsorption

Al-Nami et al. (2019)

Roots

Copper

2 M HNO3

Mixed

5,10,15, 20, 25 and 30 ppm; 25, 30, 35, 40 and 45 °C 79.1 % for 30 ppm at 25 °C Mixed

WL, PP, EFM, EIS, SEM, AFM, FTIR, Thermo-metric Tafel, TFIR, SEM, MD, PP, LPR, Quantum chemical calculations

304 stainless steel

Haruna et al. (2021)

Physical adsorption

Roots

2M HCl

CO2 saturated 3.5 wt% NaCl solution

25, 50,100, 150 and 200 ppm; 25, 40, 50 and 70 °C

Physical adsorption

Fouda et al. (2017)

Leaves Mild steel

93 % for 200 ppm at 50 °C Mixed