الفهرس 
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Abstract
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SUMMARY
This thesis deals with the study of the effect of organic additives on the electroplating process in acidified CuSO4 solution using electrolytic cell containing copper or steel cathode.
The thesis includes three chapters: introduction, experimental and results discussion. also the thesis contains references, arabic and english summary and aim of the investigation.
The first chapter presents the introduction and theoretical background for electroplating, mass transfer during electrolysis and additives in copper plating solutions as well as the literature survey on the previous work.
The second chapter is devoted for the measurements of density and viscosity in presence of organic additive mixtures at different temperatures. The cell used and the procedure of measuring the limiting current is also explained. The organic additives used are urea, formamide, dimethylformamide, acetamide, propionamide, benzamide and EDTA.
The third chapter is devoted for the results and discussion obtained. The results of change of the volt with current obtained in absence and in presence of organic additives, with different concentrations of organic additives for cell using copper cathode and steel cathode are given.
We found that the average limiting current density decreases by increase the electrode height due to increasing the hydrodynamic boundary layer .
The limiting current density increases as CuSO4 concentration increase due to the increased free Cu++ ion concentration.
Organic substances have an accelerating effect on the limiting current depending on the concentration and type of accelerator as well as cathode type. The order of acceleration in case of (Cu-Cu) is:
EDTA>dimethylformamide>propionamide>acetamide formamide> urea> benzamide.
The viscosity of electrolyte solution containing organic additive is lower than that of blank solution which increases mass transfer of Cu++ ions
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Using RCE we found that the rate of electroplating increases by increasing the speed of rotation which support that reaction is diffusion controlled reaction.
The rate of electroplating increases by increasing temperature, indicating that the mass transfer increased.
The values of thermodynamic parameters and activation energy were calculated. It is found that values of activation energy below 28 kJ mol-1 indicating that the reaction is diffusion controlled rection. also it is found that there is weak dependence of free energy of activation ΔG* on the compensation of organic additive due to compensation between ΔH* and ΔS* for given temperature. Also it is found that values of ΔS* are highly negative indicating more ordered distribution of ions.
The dimensionless groups were calculated. The exponent of Re is about 0.715 indicating a turbulent flow of ions. The general correlation in presence of organic additives was:
Organic additive Copper Cylinder Steel Cylinder
Methylamine
Sh = 0.089 Re0.716 Sc0.33
average deviation ±0.067%
Sh = 0.088 Re0.718 Sc0.33
average deviation ± 0.064%
Ethylamine
Sh = 0.089 Re0.717 Sc0.33
average deviation ± 0.07 %
Sh = 0.09 Re0.717 Sc0.33
average deviation ± 0.072 %
Diethylamine
Sh = 0.089 Re0.717Sc0.33
average deviation ± 0.079 %
Sh = 0.09 Re 0.716 Sc0.33
average deviation ± 0.089 %
Triethylamine
Sh = 0.092 Re0.715 Sc0.33
average deviation ±0.085 %
Sh = 0.092 Re 0.715 Sc0.33
average deviation ± 0.11 %
Diethanolamine
Sh = 0.093 Re 0.714 Sc 0.33
average deviation ± 0.096 %
Sh = 0.092 Re 0.715 Sc0.33
average deviation ± 0.12%
Triethanolamine
Sh =0.093 Re0.714Sc0.33
average deviation ± 0.10 %
Sh = 0.092 Re0.716 Sc0.33
average deviation ± 0.142 %
EDTA
Sh = 0.094 Re 0.714Sc 0.33
average deviation ± 0.12 %
Sh = 0.091 Re0.716 Sc0.33
average deviation ± 0.148 %