Presented by: Dr. Maissa Salah El-Din Esmail Ahmed

1. Arghel Extract as an Environmentally FriendlyAnti-Corrosion and Anti-Scalent in Industrial Water Systems Presented by: Dr. Maissa Salah El-Din Esmail Ahmed General Manger of Quality & Environment Department Alexandria Water Company

2. Arghel Extract as an Environmentally FriendlyAnti-Corrosion and Anti-Scalent in Industrial Water Systems Supervisors: Prof. Dr. Essam Khamis Ibrahim Prof. Dr. Mohamed Essam El-Din El-Rafey Prof. Dr. Ashraf Moustafa Abdel-Gaber Dr. Ahmed Mohamed Ahmed Hefnawy

3. INTRODUCTION

4. INTRODUCTION • Water is the most commonly used cooling fluid to remove excess heat from heat transfer surfaces. • long holding time at higher temperatures, higher pH, higher pressure in the presence of higher dissolved solids concentration produces more severescaling and corrosionon heat exchangers.

5. Scalling

6. INTRODUCTION Mechanism of Scale Formation Homogenous & heterogeneous nucleation Formed of three stages: • Nucleation • Crystal Growth • The final stage is total coverage

7. Scale Problems • It is common that Calcium Carbonate scale to adhere to the inner wall of the pipes. This causes the following problems in the pipe networks: 1.Reduction in the flow rate. It can block the fluid to flow in water pipes by: -clogging perforations or - forming a thick lining in production tubing. This may require increased pressure & temperature to maintain the water flow. 2. Reduction in the efficiency of heat exchangers. 3. Increasing the maintenance cost associated with operating systems using water conduits.

8. Scale Control

9. INTRODUCTION • Scale formation can be controlled by several methods: • Acid feed. • Softening. • Mechanical methods. • Antiscalent.

10. INTRODUCTION • The hazardous effect of most synthetic scale inhibitors were the motivation for studying of possible use of eco-friendly extract as a scale inhibitor .

11. INTRODUCTION WHY USING “GREEN” CHEMICAL TREATMENTS Herbs are used in alternative medicine as an effective remedy for many diseases and used safely in food. To replace the toxic corrosion inhibitors and antiscalent chemicals used widely in industry • NON TOXIC The extraction process needs no complex steps to prepare the required green inhibitors. • ENVIRONMENTALLY FRIENDLY • LOW OPERATING COST 1 January 2020 11

12. Herbs Major Constituents ArghelGlycoside,Choline CorianderLinalool, Coriandrol, Phenolic acid MarjoramThymol, Carvacrol HennaGallic acid, Dextrose FennelAnethole, Fenchone Lupine Alkaloids: Dextro-lupanin,inactive lupanin DamsissaLactones, damsin, ambrosin, coumarins Black CuminSaponin (40% melantin), volatile oil AlgaeFatty acids, amino acids, glycoproteins, crude proteins, carbohydrates, ash, crude fibers and mineral elements Investigated Herbs Plants and their Active Ingredient حرجل علاج أمراض الكبد والكلى والحساسية والكحة مرجرام – برداقوش - السمسق مسكن، مهدئ للتقلصات العضلية طحالب بحرية غذاء 1 January 2020 12

13. Corrosion

14. INTRODUCTION Corrosion and Rust Problems • Corrosion is the result of some bacterial and/or chemical reactions inside pipes. • Rust is a combination of trivalent iron with oxygen i.e. ferric oxide (Fe2O3).

15. INTRODUCTION World Consumption of chemical corrosion inhibitors Replace of active toxic agents by green chemical corrosion inhibitors

16. Aim of the work • This study seeks to investigate the efficiency of herb (arghel) extract as a novel environmentally scale and corrosion inhibitor for simulated cooling water solution. Mineral scales and corrosion were deposited from the brine solution.

17. MATERIALS

18. MATERIALS Materials Used in this Study

19. MATERIALS Main chemical compound isolated and identified from the Arghel extracts. Glycoside Choline Phytosterols α-Amyrin β-Amyrin 19

20. EXPERIMENTAL METHODS

21. EXPERIMENTALMETHODS Conductivity test Infra Red examination I- Antiscalent Characteristics Scanning electron microscope examination Electrochemical technique Optical Microscope Examination

22. EXPERIMENTALMETHODS Electrochemical impedance Technique Potentiodynamic polarization technique II- Anticorrosion characteristics Electrochemical technique using Gammry Instrument

23. RESULT & DISCUSSION

24. RESULTS&DISCUSSIONS I. Antiscalent Characteristics of Areghel Extract

25. Conductivity mesureament

26. RESULTS&DISCUSSIONS Conductivity mesureament The solution becomes supersaturated, where a rapid precipitation of CaCO3 begins accompained with a decrease of conductivity. Conductivity of the solution increases linearly with increasing Na2CO3 [Ca2+][CO32-] > Ksp Further addition of Na2CO3 produces more ions in the solution that increases the conductivity Variation of conductivity of 0.1 M CaCl2 solution with volume of 0. 1M Na2CO3.

27. RESULTS&DISCUSSIONS Variation of conductivity of 0.1 M CaCl2 solution in the absence and presence of different concentration of Arghel extracts with the volume of 0.1 M Na2CO3 at 25o C. The same behavior in presence of extracts

28. RESULTS&DISCUSSIONS Dependence of point of supersaturation on the concentration of arghel extracts The figure displays that increasing the concentration of arghel extracts increases point of supersaturation. arghel leaves extract provided more retardation of Calcium Carbonate scale than others.

29. RESULTS&DISCUSSIONS 2. Electrochemical Measurements

30. RESULTS&DISCUSSIONS a. Chronoamperometry Measurements

31. RESULTS&DISCUSSIONS Nucleation region Total blocking region Growth region • Chronoamperometry curve for polarized steel electrode in the CaC12 brine solution at 40oC for 20 hour.

32. RESULTS&DISCUSSIONS chronoamperometry curve for polarized steel electrode in the CaC12 brine solution in absence and presence of different concentration of Arghel leaves extract at 40oC.

33. RESULTS&DISCUSSIONS Variation of current density after polarizing the steel electrode for 20 hour in CaC12 brine solution in containing different concentration of arghel extracts.

34. b. Impedance Measurements RESULTS&DISCUSSIONS • The use of impedance technique can improve the understanding of the electrochemical scaling process.

35. RESULTS&DISCUSSIONS i. Blank

36. RESULTS&DISCUSSIONS Nyquist plots, measured at open circuit potential in renewed CaCl2 brine solution, for the steel electrode that was cathodically polarized in the CaCl2 brine solution for 1,3, and 20 hours. Equivalent circuit model used to determine the impedance parameters for scale process in the CaCl2 brine solution. Rs represents the solution resistance, Rf is the resistance associated with the layer of products formed during immersion, and Rct corresponds to the charge transfer resistance. CPEf and CPEdl are the constant phase elements corresponding to film and double layer capacitance. Rs and Rct increase with increasing timeof exposure

37. RESULTS&DISCUSSIONS ii. ImpedanceMeasurements for Arghelleaves extract at open circuit

38. RESULTS&DISCUSSIONS Size of semicircle decreased with Increasing concentration of extract Indicating that increasing inhibitive scale efficiency of extract with increasing concentration

39. RESULTS&DISCUSSIONS % scale inhibition = [(Rct)0 - (Rct)i] / (Rct)0*100(Rct)0 and (Rct)iare the charge transfer resistances in the absence and presence of scale inhibitor Dependence of the percentage of scale inhibition on the concentration of arghel extracts. % of scale inhibition Increased with increasing concentration of antiscalent

40. RESULTS&DISCUSSIONS Optical Microscopic Examination

41. RESULTS&DISCUSSIONS Optical micrograph photo (40X) for cathodically polarized steel electrode in CaC12 brine solution in absence and presence of different concentration of arghel leaves extract. Complete surface coverage by extremely dense scale crystals blank steel In presence of optimum dose of arghel extract can extremely inhibit formation of scale layer Optimum dose of Arghel

42. RESULTS&DISCUSSIONS Scanning Electron Microscopic Examination

43. RESULTS&DISCUSSIONS Calcite CaCO3 crystals i Aragonite CaCO3 crystals SEM micrographs of: • nonpolarized steel electrode • (b-e) Calcium carbonate grown on the surface of polarized steel electrode at -0.9 V vs. SCE for 20 h in the CaCl2 brine solution ii • Calcite • Aragonite CaCO3 crystals

44. RESULTS&DISCUSSIONS As seen, the addition of antiscalent modify the calcite CaCO3crystal into Aragonite crystals • SEM micrographs of calcium carbonate grown on the surface of polarized steel electrode at -0.9 V vs. SCE for 20 h in the CaCl2 brine solution in presence of optimum dose of Arghel Leaves extract.

45. RESULTS&DISCUSSIONS II. Anticorrosion Characteristics of arghel Extracts

46. RESULTS&DISCUSSIONS 1. Electrochemical Impedance Spectroscopy Results were done at rest potential

47. RESULTS&DISCUSSIONS Nyquist Plot Size of semicircle increased with Increasing concentration of extract Indicating that increasing inhibitive corrosion efficiency of extract with increasing concentration

48. RESULTS&DISCUSSIONS % corrosion inhibition = %ח = [1- (Rct. / Rct )]* 100(Rct)0 and (Rct)are the charge transfer resistances in the absence and presence of scale inhibitor Dependence of the percentage of corrosion inhibition on the concentration of arghel extracts. % of corrosion inhibition Increased with increasing concentration of inhibitor

49. RESULTS&DISCUSSIONS 2. Potentiodynamic Polarization Results

50. RESULTS&DISCUSSIONS Arghel extract shifts Ecorr to more noble values.