الفهرس 
Chapter 1Only 14 pages are availabe for public view
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Abstract
This thesis includes 3 chapters. The first chapter consists of introduction which presented the anodic dissolution of metals, overall description of electropolishing , basic properties of carbon steel and phosphoric acid and the chemistry of them, electropolishing inhibition and inhibitors, theories and fundamental aspects of electropolishing process, mass transfer ( in presence of natural and forced convection), Current distribution and its problems, variables affecting the limiting current, study of the adsorption phenomenon and adsorption isotherm, applications of elevtropolishing and literature survey on the previous work and the aim of work are also included in this chapter.
The second chapter is devoted for the experimental work, which represented solution composition, the apparatus used and the procedure of measuring the limiting current of carbon steel electropolishing in case of natural convection (vertical carbon steel plates) and forced convection (rotating cylinder electrode) in the absence and presence of protic solvents (methanol, ethanol, propanol, iso-propanol, ethylene glycol, and glycerol). Also this chapter contains the methods of measurements of physical properties of solution
(density, viscosity, diffusion coefficient) at 298K in the range of concentration ( Xi =0.10-0.51) of protic solvents and this chapter shows the method used for surface characterization (Scan electron microscope) in the absence and presence of protic solvents.
The third chapter is devoted for the results and discussion which consists of the evaluation of effect of the protic solvents on the electropolishing of vertical plates of carbon steel (natural convection) in 8M phosphoric acid. This search includes the study of the effect of the following factors:
1- The protic solvents concentrations
2- The temperature and activation energy parameters of the electropolishing process.
3- Adsorption isotherms.
4- Surface analysis.
Also this chapter consists of the effect of using rotating cylinder electrode to investigate the electropolishing behavior of carbon steel in presence of protic solvents. The electropolishing of carbon steel was studied in 8M H3PO4 as a function of the protic solvents concentrations and this work includes study of the effect of the following factors:
• Effect of stirring
• Mass transport
• Data correlation
It is cleared out that the electropolishing as diffusion- controlled electrochemical process which takes place at the limiting current (i.e the diffusion layer becomes saturated with Fe2+) whose value determines the rate of electropolishing and it was found that:
• The addition of protic solvents to the electropolishing solution results in a lower limiting current. This confirms the mass transport of dissolved species from anode surface to the bulk of solution as the rate determine step in presence of the protic solvents in all concentrations investigated.