| Titre : | Corrosion inhibition of C45 steel in 0.5M HCl medium by rosemary extract |
| Auteurs : | MESMOUDI Safa Elkouloub, Auteur ; MARMI Rayane, Auteur ; Malika Nouadji, Directeur de thèse |
| Type de document : | Monographie imprimée |
| Editeur : | Biskra [Algérie] : Faculté des Sciences Exactes et des Sciences de la Nature et de la Vie, Université Mohamed Khider, 2022 |
| Format : | 1 vol. (48 p.) |
| Langues: | Anglais |
| Mots-clés: | corrosion, inhibitors, rosemary extract, adsorption. |
| Résumé : |
The objective of this work is to study the corrosion inhibition of C45 steel by a green inhibitor. The inhibitor used in this work is rosemary extract with 0.5M HCl as a corrosive medium. This study was carried out by the weight loss method also the surface analyses of C45 steel by XRD and optical microscopy. In the weight loss method, we studied the effect of concentration, immersion time, and temperature on the corrosion process of C45 steel in a 0.5M HCl acid medium in the absence and presence of an inhibitor. The results obtained reflect the inhibition efficiency is increased by increasing the concentration of the inhibitor in the electrolyte solution until it reaches 74.2350% at 0.7692 g/L, and it increased by increasing the immersion time, while the inhibition efficiency decreases with increasing temperature. The values of the thermodynamic coefficients for the adsorption of the rosemary extract inhibitor on the metal surface proved that this adsorption is physical adsorption and it pursues the Langmuir model. Observation by X-ray diffraction (XRD) and optical microscopy (OM) confirms the presence of a protective layer formed on the surface of C45 steel for the inhibitor in a 0.5M HCl medium. |
| Sommaire : |
List of Figures........ IV List of Tables ......... VII General introduction ...... 1 CHAPTER I: Bibliographical Research I.1. Introduction .... 3 I.2. Definition of corrosion ........ 3 I.3. Types of corrosion ............. 3 I.3.1. Chemical corrosion (dry) ...... 3 I.3.2. Biochemical corrosion (bacterial) ....... 4 I.3.3. Electrochemical corrosion (wet) ...........4 I.4. Mechanism of corrosion ....... 4 I.5. Corrosion Inhibitors ........ 6 I.5.1. Definition ................ 6 I.5.2. Classifications of corrosion inhibitors ..... 6 I.5.2.1. Chemical nature.......... 7 I.5.2.1.1. Organic inhibitors ........... 7 I.5.2.1.2. Inorganic inhibitors ........... 7 I.5.2.2. Mechanism of electrochemical action ......... 8 I.5.2.2.1. Anodic inhibitors ............ 8 I.5.2.2.2. Cathodic inhibitors .......... 8 I.5.2.2.3. Mixed inhibitors ............. 8 I.5.2.3. Mechanisms of interface action......... 9 I.5.2.3.1. Adsorption on the metal surface ....... 9 I.5.2.3.2. Formation of a protective film ............ 10 I.5.2.4. Application domain ............ 10 I.5.3. Green corrosion inhibitors ........11 I.5.3. Mechanism of corrosion inhibition ................ 12 I.6. Influence of concentration on inhibitory effect .......... 13 I.6.1. Langmuir isotherm .......... 13 I.6.2.Temkin isotherm .............. 14 CONTENTS II I.6.3.Freundlich isotherm ............ 15 I.6.4.Frumkin isotherm ................ 16 I.6.5.Flory Huggins isotherm ........ 17 I.6.6. El-Alwady isotherm ............ 18 CHAPTER II: Experimental Methods II.1. Introduction ......... 19 II.2. Materials and products ........... 19 II.2.1. Materials ........... 19 II.2.2. Products ............ 19 II.3. Experimental Method...... 19 II.3.1. Specimens Preparation ...... 19 II.3.1.1. Studied Specimens ............ 19 II.3.1.2. Mechanical Polishing ......... 20 II.3.2. Solutions Preparation ......... 20 II.3.2.1. Electrolytic Solution ........ 20 II.3.2.2. Inhibitor Solution ............ 21 II.4. Test Methods ..................... 22 II.4.1. Weight Loss Method ............. 22 II.4.1.1. Weight Loss Method Theory and Principle ....... 22 II.4.1.2.Weight Loss Method Processing ................. 23 II.5. Analysis Methods ................................. 24 II.5.1. X-ray Powder diffraction (XRD) ............ 24 II.5.2. Optical Microscope......... 25 CHAPTER III: Results and discussions III.1. Introduction ...................... 27 III.2. Gravimetric study ................ 27 III.2.1. Effect of concentration ......... 27 III.2.2. Effect of immersion time......... 29 III.2.3. Effect of temperature ....................... 32 III.2.3.1. Determination of activation energy ........ 35 III.2.4. Adsorption isotherm ................... 37 III.2.4.1.Free Energy of Adsorption ............ 41 CONTENTS III III.3. Structural study .............. 42 III.3.1. X-ray diffraction ......................... 42 III.3.2. Optical microscopy studies ................. 45 General conclusion .............. 46 Bibliographic References ......... 48 |
Disponibilité (1)
| Cote | Support | Localisation | Statut |
|---|---|---|---|
| MPHY/611 | Mémoire master | bibliothèque sciences exactes | Consultable |
