الفهرس 
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Abstract
SUMMARY
This thesiThis thesis deals with the study of the effect of surfactants as organic additives on n the onondepositin process of copper and nickel using different baths and organized into three chapters.
In the first Chapter, introduction that consists of following topics:
• Theoretical background for copper electrodeposition.
• Mass transfer during electrolysis.
• Dimensional analysis method.
• Electrowining process.
• Overview of nickel electroplating, basics and content of plating bath.
• Effect of additives on electrodeposition kinetics.
• The literature survey on the previous
• Aim of the work
The second chapter devoted for the experimental method used in this thesis. the cell used and the procedure of measuring the limiting current in both cases of copper electrodeposition and copper electrowining using lead as insoluble anode also the Wath’s bath of nickel electroplating is explained.
The organic additives used are :
Sodium Dodecyl Sulphate
Cetyl Trimethyl Ammonium Bromide
In addition, this chapter contains the methods of measurements of physical properties of solution (density and viscosity) at different concentrations and temperatures in absence and presence of surfactants.
In the third Chapter, results and discussion obtained and includes two parts:
Part I
This part investigates the effect of these surfactants on the copper electrodeposition from acidic sulphate bath. The primary characteristics studied included limiting current inhibitor efficiency, acceleration efficiency, different models of adsorption isotherm, temperature, mixed surfactants, rotation, deposit morphology. As a result:
• The presence of Triton x-100 and Sodium Dodecyl Sulphate had a major negative impact of limiting current. While Cetyl Trimethyl Ammonium Bromide had positive impact on limiting current.
• The values of %inhibition (%I) increase with increasing inhibitor concentration and decrease slightly with temperature.
• The values of %acceleration increase with increasing accelerator concentration and increase slightly with temperature.
• The adsorption of all inhibitors on copper surface obeys Temkin, Flory-Huggins and kinetic adsorption isotherm.
• The values of (K ads.) and (ΔGads.) indicated that all the inhibitors strongly adsorbed on copper surface.
• The Ea values of the electrodeposition reaction for the inhibited solutions are higher than that for the uninhibited solutions indicating good inhibitor characteristics associating with physical adsorption. So the trend of inhibition of investigated surfactants as follow :
Sodium Dodecyl Sulphate > Triton x-100
• The values of %inhibition (%I) decrease in presence of mixed surfactants than in presence of single surfactant.
• Using RCE and at 25°C, we found that the limiting current density increase by increasing the speed of rotation, then the reaction is diffusion controlled.
The values of thermodynamics parameters ΔH* (kJmol-1), ΔS* (J.mol-1 k-1) and ΔG* (kJmol-1) are represented. The results show positive sign for ΔH*, reflecting the endothermic nature of the adsorption process. The negative values of ΔS* pointed to greater order produced during the process of activation. ΔG* values show limited increase with rise in the concentration of surfactants i.e.: ΔG* values of inhibited systems were more positive than that for the uninhibited systems. The isokinetic temperature β were estimate, their values are much higher than that of the experimental temperature 298K indicating that the rate of the reaction is enthalpy controlled. The dimensionless groups Sh (Sherwood number), Sc (Schmidt number) and Re (Reynolds number) were calculate and the relations between them were given. The general correlation in presence of all surfactants was:
Sh = 0.53 Re0.70 Sc0.33 for Triton x-100
Sh=0.54Re0.70 Sc0.33 for SDS
Sh=O.53Re0.70 Sc0.33 for CTAB
The exponents form last equation denotes a highly turbulent flow. In addition, a forced convection mechanism is obtained which agree very well with similar relationships reported before.
• Addition of these surfactants to copper bath exhibits a strong influence on the microstructure that refining the deposit. By increasing their concentration, the deposits are strongly adherent and uniformly cover the entire electrode surface.
• Also studies the electrodeposition of copper using lead as insoluble anode. The values of mass transfer (k) were reported, they are directly proportional to those of the limiting current density, decrease by increasing Triton x-100 and Sodium Dodecyl Sulphate concentrations and increase by increasing Cetyl Trimethyl Ammonium Bromide.
Part II
This part deals with the nickel electrodeposition on copper .It is well known that the structure and surface properties are strongly influenced by presence and concentration of surfactants in the bath and hydrodynamics. The results show:
• Surfactants play important role on the deposition process of nickel from Watt’s bath that by using small concentration of them can act as a brightener for the nickel
Also we study the surface morphology.