الفهرس 
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Abstract
This thesis deals with the study of the effect of different organic alcohols on the electropolishing of copper in H3PO4 by measuring the limiting current and weight loss.
This thesis includes three parts:
The first chapter includes, the introduction which deals with definition of the electropolishing process, the mechanism of the process, effect of various factors on electropolishing in addition to the behaviour of corrosion inhibitors and the related literature.
The second chapter deals with the experimental part which involves the chemicals, solutions, and the apparatus used. It includes also experimental measurements of density and viscosity of alcohols-water-phosphoric acid mixtures at different temperatures, the cell used and procedure of measuring limiting current at different conditions.
The third chapter is devoted to the results obtained and discussion which deals with the effect of different factors on the limiting current. It is found that the limiting current density decreases with increasing the electrode height due to increasing the thermodynamic boundary layer. A comparison between electropolishing using divided and undivided cells shows that the rate of electropolishing in the undivided cell is higher than in case of divided cell due to the presence of H2 in the first cell which increases the polishing rate. The inhibition of the electropolishing of copper by addition of the organic alcohols with different concentrations in the range (2, 5, 10, 15, 20, 25 and 30 %) are studied and the percentage inhibition was found to vary from 4.3 to 53.8 % in case of divided cell depending on type of alcohols and their concentration. Adsorption of these organic additives obeys Flory-Huggins and Kinetic adsorption isotherms but not Langmuir isotherm. The values of thermodynamic parameters and activation energy are calculated. It is found that the values of activation energy are less than 40 Kj / mol for all inhibitors which indicates that the reaction is diffusion controlled. The dimensionless group is calculated. The exponent of Re is about 0.717 indicating turbulent flow of ions.
The general correlations in presence of organic substance were:
I- For methanol : Sh = 0.12 Re 0.718 (Sc)0.33
2- For ethanol : Sh = 0.12 Re 0.72 (Sc)0.33
csc)0.33
3-For propanol : Sh = 0.12 Re 0.72 (Sc)0.33
4-For isopropanol : Sh = 0.085 Re 0.72 (Sc)0.33
5- For butanol : Sh = 0.126 Re 0.71 (Sc)0.33
6- For isobutanol : Sh = 0.108 Re 0.71 (Sc)0.33
7- For t-butanol : Sh = 0.107 Re 0.72 (Sc)0.33
The dissolution of copper in H3PO4 with and without organic additive is measured by weight loss method. It is found that the rate of inhibition in this case is nearly the same as in electrochemical methods.